DPI for everyone (#548)

CHANGELOG.md

@@ -1,6 +1,17 @@
 # Unreleased
 
 - **Breaking:** Removed `VirtualKeyCode::LMenu` and `VirtualKeyCode::RMenu`; Windows now generates `VirtualKeyCode::LAlt` and `VirtualKeyCode::RAlt` instead.
+- On X11, exiting fullscreen no longer leaves the window in the monitor's top left corner.
+- **Breaking:** `Window::hidpi_factor` has been renamed to `Window::get_hidpi_factor` for better consistency. `WindowEvent::HiDPIFactorChanged` has been renamed to `WindowEvent::HiDpiFactorChanged`. DPI factors are always represented as `f64` instead of `f32` now.
+- The Windows backend is now DPI aware. `WindowEvent::HiDpiFactorChanged` is implemented, and `MonitorId::get_hidpi_factor` and `Window::hidpi_factor` return accurate values.
+- Implemented `WindowEvent::HiDpiFactorChanged` on X11.
+- On macOS, `Window::set_cursor_position` is now relative to the client area.
+- On macOS, setting the maximum and minimum dimensions now applies to the client area dimensions rather than to the window dimensions.
+- On iOS, `MonitorId::get_dimensions` has been implemented and both `MonitorId::get_hidpi_factor` and `Window::get_hidpi_factor` return accurate values.
+- On Emscripten, `MonitorId::get_hidpi_factor` now returns the same value as `Window::get_hidpi_factor` (it previously would always return 1.0).
+- **Breaking:** The entire API for sizes, positions, etc. has changed. In the majority of cases, winit produces and consumes positions and sizes as `LogicalPosition` and `LogicalSize`, respectively. The notable exception is `MonitorId` methods, which deal in `PhysicalPosition` and `PhysicalSize`. See the documentation for specifics and explanations of the types. Additionally, winit automatically conserves logical size when the DPI factor changes.
+- **Breaking:** All deprecated methods have been removed. For `Window::platform_display` and `Window::platform_window`, switch to the appropriate platform-specific `WindowExt` methods. For `Window::get_inner_size_points` and `Window::get_inner_size_pixels`, use the `LogicalSize` returned by `Window::get_inner_size` and convert as needed.
+- HiDPI support for Wayland.
 
 # Version 0.15.1 (2018-06-13)
 

Cargo.toml

@@ -43,6 +43,7 @@ features = [
     "objbase",
     "processthreadsapi",
     "shellapi",
+    "shellscalingapi",
     "shobjidl_core",
     "unknwnbase",
     "windowsx",

examples/min_max_size.rs

@@ -1,5 +1,7 @@
 extern crate winit;
 
+use winit::dpi::LogicalSize;
+
 fn main() {
     let mut events_loop = winit::EventsLoop::new();
 
@@ -7,8 +9,8 @@ fn main() {
         .build(&events_loop)
         .unwrap();
 
-    window.set_min_dimensions(Some((400, 200)));
-    window.set_max_dimensions(Some((800, 400)));
+    window.set_min_dimensions(Some(LogicalSize::new(400.0, 200.0)));
+    window.set_max_dimensions(Some(LogicalSize::new(800.0, 400.0)));
 
     events_loop.run_forever(|event| {
         println!("{:?}", event);

examples/resizable.rs

@@ -7,7 +7,7 @@ fn main() {
 
     let window = winit::WindowBuilder::new()
         .with_title("Hit space to toggle resizability.")
-        .with_dimensions(400, 200)
+        .with_dimensions((400, 200).into())
         .with_resizable(resizable)
         .build(&events_loop)
         .unwrap();

src/dpi.rs

@@ -0,0 +1,307 @@
+
+//! DPI is important, so read the docs for this module if you don't want to be confused.
+//!
+//! Originally, `winit` dealt entirely in physical pixels (excluding unintentional inconsistencies), but now all
+//! window-related functions both produce and consume logical pixels. Monitor-related functions still use physical
+//! pixels, as do any context-related functions in `glutin`.
+//!
+//! If you've never heard of these terms before, then you're not alone, and this documentation will explain the
+//! concepts.
+//!
+//! Modern screens have a defined physical resolution, most commonly 1920x1080. Indepedent of that is the amount of
+//! space the screen occupies, which is to say, the height and width in millimeters. The relationship between these two
+//! measurements is the *pixel density*. Mobile screens require a high pixel density, as they're held close to the
+//! eyes. Larger displays also require a higher pixel density, hence the growing presence of 1440p and 4K displays.
+//!
+//! So, this presents a problem. Let's say we want to render a square 100px button. It will occupy 100x100 of the
+//! screen's pixels, which in many cases, seems perfectly fine. However, because this size doesn't account for the
+//! screen's dimensions or pixel density, the button's size can vary quite a bit. On a 4K display, it would be unusably
+//! small.
+//!
+//! That's a description of what happens when the button is 100x100 *physical* pixels. Instead, let's try using 100x100
+//! *logical* pixels. To map logical pixels to physical pixels, we simply multiply by the DPI factor. On a "typical"
+//! desktop display, the DPI factor will be 1.0, so 100x100 logical pixels equates to 100x100 physical pixels. However,
+//! a 1440p display may have a DPI factor of 1.25, so the button is rendered as 125x125 physical pixels. Ideally, the
+//! button now has approximately the same perceived size across varying displays.
+//!
+//! Failure to account for the DPI factor can create a badly degraded user experience. Most notably, it can make users
+//! feel like they have bad eyesight, which will potentially cause them to think about growing elderly, resulting in
+//! them entering an existential panic. Once users enter that state, they will no longer be focused on your application.
+//!
+//! There are two ways to get the DPI factor: either by calling
+//! [`MonitorId::get_hidpi_factor`](../struct.MonitorId.html#method.get_hidpi_factor), or
+//! [`Window::get_hidpi_factor`](../struct.Window.html#method.get_hidpi_factor). You'll almost always use the latter,
+//! which is basically equivalent to `window.get_current_monitor().get_hidpi_factor()` anyway.
+//!
+//! Here's an overview of what sort of DPI factors you can expect, and where they come from:
+//! - **Windows:** On Windows 8 and 10, per-monitor scaling is readily configured by users from the display settings.
+//! While users are free to select any option they want, they're only given a selection of "nice" DPI factors, i.e.
+//! 1.0, 1.25, 1.5... on Windows 7, the DPI factor is global and changing it requires logging out.
+//! - **macOS:** The buzzword is "retina displays", which have a DPI factor of 2.0. Otherwise, the DPI factor is 1.0.
+//! Intermediate DPI factors are never used, thus 1440p displays/etc. aren't properly supported. It's possible for any
+//! display to use that 2.0 DPI factor, given the use of the command line.
+//! - **X11:** On X11, we calcuate the DPI factor based on the millimeter dimensions provided by XRandR. This can
+//! result in a wide range of possible values, including some interesting ones like 1.0833333333333333. This can be
+//! overridden using the `WINIT_HIDPI_FACTOR` environment variable, though that's not recommended.
+//! - **Wayland:** On Wayland, DPI factors are very much at the discretion of the user.
+//! - **iOS:** DPI factors are both constant and device-specific on iOS.
+//! - **Android:** This feature isn't yet implemented on Android, so the DPI factor will always be returned as 1.0.
+//!
+//! The window's logical size is conserved across DPI changes, resulting in the physical size changing instead. This
+//! may be surprising on X11, but is quite standard elsewhere. Physical size changes produce a
+//! [`Resized`](../enum.WindowEvent.html#variant.Resized) event, even on platforms where no resize actually occurs,
+//! such as macOS and Wayland. As a result, it's not necessary to separately handle
+//! [`HiDpiFactorChanged`](../enum.WindowEvent.html#variant.HiDpiFactorChanged) if you're only listening for size.
+//!
+//! Your GPU has no awareness of the concept of logical pixels, and unless you like wasting pixel density, your
+//! framebuffer's size should be in physical pixels.
+
+/// Checks that the DPI factor is a normal positive `f64`.
+///
+/// All functions that take a DPI factor assert that this will return `true`. If you're sourcing DPI factors from
+/// anywhere other than winit, it's recommended to validate them using this function before passing them to winit;
+/// otherwise, you risk panics.
+#[inline]
+pub fn validate_hidpi_factor(dpi_factor: f64) -> bool {
+    dpi_factor.is_sign_positive() && dpi_factor.is_normal()
+}
+
+/// A position represented in logical pixels.
+///
+/// The position is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
+/// which can cause noticable issues. To help with that, an `Into<(i32, i32)>` implementation is provided which
+/// does the rounding for you.
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub struct LogicalPosition {
+    pub x: f64,
+    pub y: f64,
+}
+
+impl LogicalPosition {
+    #[inline]
+    pub fn new(x: f64, y: f64) -> Self {
+        LogicalPosition { x, y }
+    }
+
+    #[inline]
+    pub fn from_physical<T: Into<PhysicalPosition>>(physical: T, dpi_factor: f64) -> Self {
+        physical.into().to_logical(dpi_factor)
+    }
+
+    #[inline]
+    pub fn to_physical(&self, dpi_factor: f64) -> PhysicalPosition {
+        assert!(validate_hidpi_factor(dpi_factor));
+        let x = self.x * dpi_factor;
+        let y = self.y * dpi_factor;
+        PhysicalPosition::new(x, y)
+    }
+}
+
+impl From<(f64, f64)> for LogicalPosition {
+    #[inline]
+    fn from((x, y): (f64, f64)) -> Self {
+        Self::new(x, y)
+    }
+}
+
+impl From<(i32, i32)> for LogicalPosition {
+    #[inline]
+    fn from((x, y): (i32, i32)) -> Self {
+        Self::new(x as f64, y as f64)
+    }
+}
+
+impl Into<(f64, f64)> for LogicalPosition {
+    #[inline]
+    fn into(self) -> (f64, f64) {
+        (self.x, self.y)
+    }
+}
+
+impl Into<(i32, i32)> for LogicalPosition {
+    /// Note that this rounds instead of truncating.
+    #[inline]
+    fn into(self) -> (i32, i32) {
+        (self.x.round() as _, self.y.round() as _)
+    }
+}
+
+/// A position represented in physical pixels.
+///
+/// The position is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
+/// which can cause noticable issues. To help with that, an `Into<(i32, i32)>` implementation is provided which
+/// does the rounding for you.
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub struct PhysicalPosition {
+    pub x: f64,
+    pub y: f64,
+}
+
+impl PhysicalPosition {
+    #[inline]
+    pub fn new(x: f64, y: f64) -> Self {
+        PhysicalPosition { x, y }
+    }
+
+    #[inline]
+    pub fn from_logical<T: Into<LogicalPosition>>(logical: T, dpi_factor: f64) -> Self {
+        logical.into().to_physical(dpi_factor)
+    }
+
+    #[inline]
+    pub fn to_logical(&self, dpi_factor: f64) -> LogicalPosition {
+        assert!(validate_hidpi_factor(dpi_factor));
+        let x = self.x / dpi_factor;
+        let y = self.y / dpi_factor;
+        LogicalPosition::new(x, y)
+    }
+}
+
+impl From<(f64, f64)> for PhysicalPosition {
+    #[inline]
+    fn from((x, y): (f64, f64)) -> Self {
+        Self::new(x, y)
+    }
+}
+
+impl From<(i32, i32)> for PhysicalPosition {
+    #[inline]
+    fn from((x, y): (i32, i32)) -> Self {
+        Self::new(x as f64, y as f64)
+    }
+}
+
+impl Into<(f64, f64)> for PhysicalPosition {
+    #[inline]
+    fn into(self) -> (f64, f64) {
+        (self.x, self.y)
+    }
+}
+
+impl Into<(i32, i32)> for PhysicalPosition {
+    /// Note that this rounds instead of truncating.
+    #[inline]
+    fn into(self) -> (i32, i32) {
+        (self.x.round() as _, self.y.round() as _)
+    }
+}
+
+/// A size represented in logical pixels.
+///
+/// The size is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
+/// which can cause noticable issues. To help with that, an `Into<(u32, u32)>` implementation is provided which
+/// does the rounding for you.
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub struct LogicalSize {
+    pub width: f64,
+    pub height: f64,
+}
+
+impl LogicalSize {
+    #[inline]
+    pub fn new(width: f64, height: f64) -> Self {
+        LogicalSize { width, height }
+    }
+
+    #[inline]
+    pub fn from_physical<T: Into<PhysicalSize>>(physical: T, dpi_factor: f64) -> Self {
+        physical.into().to_logical(dpi_factor)
+    }
+
+    #[inline]
+    pub fn to_physical(&self, dpi_factor: f64) -> PhysicalSize {
+        assert!(validate_hidpi_factor(dpi_factor));
+        let width = self.width * dpi_factor;
+        let height = self.height * dpi_factor;
+        PhysicalSize::new(width, height)
+    }
+}
+
+impl From<(f64, f64)> for LogicalSize {
+    #[inline]
+    fn from((width, height): (f64, f64)) -> Self {
+        Self::new(width, height)
+    }
+}
+
+impl From<(u32, u32)> for LogicalSize {
+    #[inline]
+    fn from((width, height): (u32, u32)) -> Self {
+        Self::new(width as f64, height as f64)
+    }
+}
+
+impl Into<(f64, f64)> for LogicalSize {
+    #[inline]
+    fn into(self) -> (f64, f64) {
+        (self.width, self.height)
+    }
+}
+
+impl Into<(u32, u32)> for LogicalSize {
+    /// Note that this rounds instead of truncating.
+    #[inline]
+    fn into(self) -> (u32, u32) {
+        (self.width.round() as _, self.height.round() as _)
+    }
+}
+
+/// A size represented in physical pixels.
+///
+/// The size is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
+/// which can cause noticable issues. To help with that, an `Into<(u32, u32)>` implementation is provided which
+/// does the rounding for you.
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub struct PhysicalSize {
+    pub width: f64,
+    pub height: f64,
+}
+
+impl PhysicalSize {
+    #[inline]
+    pub fn new(width: f64, height: f64) -> Self {
+        PhysicalSize { width, height }
+    }
+
+    #[inline]
+    pub fn from_logical<T: Into<LogicalSize>>(logical: T, dpi_factor: f64) -> Self {
+        logical.into().to_physical(dpi_factor)
+    }
+
+    #[inline]
+    pub fn to_logical(&self, dpi_factor: f64) -> LogicalSize {
+        assert!(validate_hidpi_factor(dpi_factor));
+        let width = self.width / dpi_factor;
+        let height = self.height / dpi_factor;
+        LogicalSize::new(width, height)
+    }
+}
+
+impl From<(f64, f64)> for PhysicalSize {
+    #[inline]
+    fn from((width, height): (f64, f64)) -> Self {
+        Self::new(width, height)
+    }
+}
+
+impl From<(u32, u32)> for PhysicalSize {
+    #[inline]
+    fn from((width, height): (u32, u32)) -> Self {
+        Self::new(width as f64, height as f64)
+    }
+}
+
+impl Into<(f64, f64)> for PhysicalSize {
+    #[inline]
+    fn into(self) -> (f64, f64) {
+        (self.width, self.height)
+    }
+}
+
+impl Into<(u32, u32)> for PhysicalSize {
+    /// Note that this rounds instead of truncating.
+    #[inline]
+    fn into(self) -> (u32, u32) {
+        (self.width.round() as _, self.height.round() as _)
+    }
+}

src/events.rs

@@ -1,5 +1,6 @@
 use std::path::PathBuf;
-use {WindowId, DeviceId};
+
+use {DeviceId, LogicalPosition, LogicalSize, WindowId};
 
 /// Describes a generic event.
 #[derive(Clone, Debug)]
@@ -23,12 +24,11 @@ pub enum Event {
 /// Describes an event from a `Window`.
 #[derive(Clone, Debug)]
 pub enum WindowEvent {
-
     /// The size of the window has changed. Contains the client area's new dimensions.
-    Resized(u32, u32),
+    Resized(LogicalSize),
 
     /// The position of the window has changed. Contains the window's new position.
-    Moved(i32, i32),
+    Moved(LogicalPosition),
 
     /// The window has been requested to close.
     CloseRequested,
@@ -63,7 +63,7 @@ pub enum WindowEvent {
         /// (x,y) coords in pixels relative to the top-left corner of the window. Because the range of this data is
         /// limited by the display area and it may have been transformed by the OS to implement effects such as cursor
         /// acceleration, it should not be used to implement non-cursor-like interactions such as 3D camera control.
-        position: (f64, f64),
+        position: LogicalPosition,
         modifiers: ModifiersState
     },
 
@@ -96,14 +96,16 @@ pub enum WindowEvent {
     /// Touch event has been received
     Touch(Touch),
 
-    /// DPI scaling factor of the window has changed.
+    /// The DPI factor of the window has changed.
     ///
-    /// The following actions cause DPI changes:
+    /// The following user actions can cause DPI changes:
     ///
-    /// * A user changes the resolution.
-    /// * A user changes the desktop scaling value (e.g. in Control Panel on Windows).
-    /// * A user moves the application window to a display with a different DPI.
-    HiDPIFactorChanged(f32),
+    /// * Changing the display's resolution.
+    /// * Changing the display's DPI factor (e.g. in Control Panel on Windows).
+    /// * Moving the window to a display with a different DPI factor.
+    ///
+    /// For more information about DPI in general, see the [`dpi`](dpi/index.html) module.
+    HiDpiFactorChanged(f64),
 }
 
 /// Represents raw hardware events that are not associated with any particular window.
@@ -197,7 +199,7 @@ pub enum TouchPhase {
 pub struct Touch {
     pub device_id: DeviceId,
     pub phase: TouchPhase,
-    pub location: (f64,f64),
+    pub location: LogicalPosition,
     /// unique identifier of a finger.
     pub id: u64
 }
@@ -242,7 +244,7 @@ pub enum MouseScrollDelta {
 	/// Scroll events are expressed as a PixelDelta if
 	/// supported by the device (eg. a touchpad) and
 	/// platform.
-	PixelDelta(f32, f32)
+	PixelDelta(LogicalPosition),
 }
 
 /// Symbolic name for a keyboard key.

src/lib.rs

@@ -35,14 +35,18 @@
 //!
 //! ```no_run
 //! use winit::{Event, WindowEvent};
+//! use winit::dpi::LogicalSize;
 //! # use winit::EventsLoop;
 //! # let mut events_loop = EventsLoop::new();
 //!
 //! loop {
 //!     events_loop.poll_events(|event| {
 //!         match event {
-//!             Event::WindowEvent { event: WindowEvent::Resized(w, h), .. } => {
-//!                 println!("The window was resized to {}x{}", w, h);
+//!             Event::WindowEvent {
+//!                 event: WindowEvent::Resized(LogicalSize { width, height }),
+//!                 ..
+//!             } => {
+//!                 println!("The window was resized to {}x{}", width, height);
 //!             },
 //!             _ => ()
 //!         }
@@ -80,6 +84,7 @@
 //! to create an OpenGL/Vulkan/DirectX/Metal/etc. context that will draw on the window.
 //!
 
+#[allow(unused_imports)]
 #[macro_use]
 extern crate lazy_static;
 extern crate libc;
@@ -106,14 +111,16 @@ extern crate percent_encoding;
 #[cfg(any(target_os = "linux", target_os = "freebsd", target_os = "dragonfly", target_os = "openbsd"))]
 extern crate smithay_client_toolkit as sctk;
 
+pub(crate) use dpi::*; // TODO: Actually change the imports throughout the codebase.
 pub use events::*;
 pub use window::{AvailableMonitorsIter, MonitorId};
 pub use icon::*;
 
-mod platform;
+pub mod dpi;
 mod events;
-mod window;
 mod icon;
+mod platform;
+mod window;
 
 pub mod os;
 
@@ -227,6 +234,11 @@ impl EventsLoop {
     /// Calls `callback` every time an event is received. If no event is available, sleeps the
     /// current thread and waits for an event. If the callback returns `ControlFlow::Break` then
     /// `run_forever` will immediately return.
+    ///
+    /// # Danger!
+    ///
+    /// The callback is run after *every* event, so if its execution time is non-trivial the event queue may not empty
+    /// at a sufficient rate. Rendering in the callback with vsync enabled **will** cause significant lag.
     #[inline]
     pub fn run_forever<F>(&mut self, callback: F)
         where F: FnMut(Event) -> ControlFlow
@@ -403,23 +415,23 @@ impl Default for CursorState {
 }
 
 /// Attributes to use when creating a window.
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct WindowAttributes {
     /// The dimensions of the window. If this is `None`, some platform-specific dimensions will be
     /// used.
     ///
     /// The default is `None`.
-    pub dimensions: Option<(u32, u32)>,
+    pub dimensions: Option<LogicalSize>,
 
     /// The minimum dimensions a window can be, If this is `None`, the window will have no minimum dimensions (aside from reserved).
     ///
     /// The default is `None`.
-    pub min_dimensions: Option<(u32, u32)>,
+    pub min_dimensions: Option<LogicalSize>,
 
     /// The maximum dimensions a window can be, If this is `None`, the maximum will have no maximum or will be set to the primary monitor's dimensions by the platform.
     ///
     /// The default is `None`.
-    pub max_dimensions: Option<(u32, u32)>,
+    pub max_dimensions: Option<LogicalSize>,
 
     /// Whether the window is resizable or not.
     ///

src/os/ios.rs

@@ -0,0 +1,43 @@
+#![cfg(target_os = "ios")]
+
+use std::os::raw::c_void;
+
+use {MonitorId, Window};
+
+/// Additional methods on `Window` that are specific to iOS.
+pub trait WindowExt {
+    /// Returns a pointer to the `UIWindow` that is used by this window.
+    ///
+    /// The pointer will become invalid when the `Window` is destroyed.
+    fn get_uiwindow(&self) -> *mut c_void;
+
+    /// Returns a pointer to the `UIView` that is used by this window.
+    ///
+    /// The pointer will become invalid when the `Window` is destroyed.
+    fn get_uiview(&self) -> *mut c_void;
+}
+
+impl WindowExt for Window {
+    #[inline]
+    fn get_uiwindow(&self) -> *mut c_void {
+        self.window.get_uiwindow() as _
+    }
+
+    #[inline]
+    fn get_uiview(&self) -> *mut c_void {
+        self.window.get_uiview() as _
+    }
+}
+
+/// Additional methods on `MonitorId` that are specific to iOS.
+pub trait MonitorIdExt {
+    /// Returns a pointer to the `UIScreen` that is used by this monitor.
+    fn get_uiscreen(&self) -> *mut c_void;
+}
+
+impl MonitorIdExt for MonitorId {
+    #[inline]
+    fn get_uiscreen(&self) -> *mut c_void {
+        self.inner.get_uiscreen() as _
+    }
+}

src/os/macos.rs

@@ -3,7 +3,7 @@
 use std::convert::From;
 use std::os::raw::c_void;
 use cocoa::appkit::NSApplicationActivationPolicy;
-use {MonitorId, Window, WindowBuilder};
+use {LogicalSize, MonitorId, Window, WindowBuilder};
 
 /// Additional methods on `Window` that are specific to MacOS.
 pub trait WindowExt {
@@ -86,7 +86,7 @@ pub trait WindowBuilderExt {
     /// Makes the window content appear behind the titlebar.
     fn with_fullsize_content_view(self, fullsize_content_view: bool) -> WindowBuilder;
     /// Build window with `resizeIncrements` property. Values must not be 0.
-    fn with_resize_increments(self, width_inc: u32, height_inc: u32) -> WindowBuilder;
+    fn with_resize_increments(self, increments: LogicalSize) -> WindowBuilder;
 }
 
 impl WindowBuilderExt for WindowBuilder {
@@ -133,8 +133,8 @@ impl WindowBuilderExt for WindowBuilder {
     }
 
     #[inline]
-    fn with_resize_increments(mut self, width_inc: u32, height_inc: u32) -> WindowBuilder {
-        self.platform_specific.resize_increments = Some((width_inc, height_inc));
+    fn with_resize_increments(mut self, increments: LogicalSize) -> WindowBuilder {
+        self.platform_specific.resize_increments = Some(increments.into());
         self
     }
 }

src/os/mod.rs

@@ -3,6 +3,7 @@
 //! Contains the follow modules:
 //!
 //!  - `android`
+//!  - `ios`
 //!  - `macos`
 //!  - `unix`
 //!  - `windows`
@@ -10,6 +11,7 @@
 //! However only the module corresponding to the platform you're compiling to will be available.
 //!
 pub mod android;
+pub mod ios;
 pub mod macos;
 pub mod unix;
 pub mod windows;

src/os/unix.rs

@@ -1,14 +1,20 @@
 #![cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd"))]
 
 use std::os::raw;
-use std::sync::Arc;
 use std::ptr;
-use EventsLoop;
-use MonitorId;
-use Window;
-use platform::EventsLoop as LinuxEventsLoop;
-use platform::Window as LinuxWindow;
-use WindowBuilder;
+use std::sync::Arc;
+
+use {
+    EventsLoop,
+    LogicalSize,
+    MonitorId,
+    Window,
+    WindowBuilder,
+};
+use platform::{
+    EventsLoop as LinuxEventsLoop,
+    Window as LinuxWindow,
+};
 use platform::x11::XConnection;
 use platform::x11::ffi::XVisualInfo;
 
@@ -72,6 +78,7 @@ impl EventsLoopExt for EventsLoop {
     }
 
     #[inline]
+    #[doc(hidden)]
     fn get_xlib_xconnection(&self) -> Option<Arc<XConnection>> {
         self.events_loop.x_connection().cloned()
     }
@@ -93,6 +100,7 @@ pub trait WindowExt {
 
     fn get_xlib_screen_id(&self) -> Option<raw::c_int>;
 
+    #[doc(hidden)]
     fn get_xlib_xconnection(&self) -> Option<Arc<XConnection>>;
 
     /// Set window urgency hint (`XUrgencyHint`). Only relevant on X.
@@ -155,6 +163,7 @@ impl WindowExt for Window {
     }
 
     #[inline]
+    #[doc(hidden)]
     fn get_xlib_xconnection(&self) -> Option<Arc<XConnection>> {
         match self.window {
             LinuxWindow::X(ref w) => Some(w.get_xlib_xconnection()),
@@ -211,9 +220,9 @@ pub trait WindowBuilderExt {
     /// Build window with `_NET_WM_WINDOW_TYPE` hint; defaults to `Normal`. Only relevant on X11.
     fn with_x11_window_type(self, x11_window_type: XWindowType) -> WindowBuilder;
     /// Build window with resize increment hint. Only implemented on X11.
-    fn with_resize_increments(self, width_inc: u32, height_inc: u32) -> WindowBuilder;
+    fn with_resize_increments(self, increments: LogicalSize) -> WindowBuilder;
     /// Build window with base size hint. Only implemented on X11.
-    fn with_base_size(self, base_width: u32, base_height: u32) -> WindowBuilder;
+    fn with_base_size(self, base_size: LogicalSize) -> WindowBuilder;
 }
 
 impl WindowBuilderExt for WindowBuilder {
@@ -250,14 +259,14 @@ impl WindowBuilderExt for WindowBuilder {
     }
 
     #[inline]
-    fn with_resize_increments(mut self, width_inc: u32, height_inc: u32) -> WindowBuilder {
-        self.platform_specific.resize_increments = Some((width_inc, height_inc));
+    fn with_resize_increments(mut self, increments: LogicalSize) -> WindowBuilder {
+        self.platform_specific.resize_increments = Some(increments.into());
         self
     }
 
     #[inline]
-    fn with_base_size(mut self, base_width: u32, base_height: u32) -> WindowBuilder {
-        self.platform_specific.base_size = Some((base_width, base_height));
+    fn with_base_size(mut self, base_size: LogicalSize) -> WindowBuilder {
+        self.platform_specific.base_size = Some(base_size.into());
         self
     }
 }

src/os/windows.rs

@@ -5,7 +5,25 @@ use std::os::raw::c_void;
 use libc;
 use winapi::shared::windef::HWND;
 
-use {DeviceId, Icon, MonitorId, Window, WindowBuilder};
+use {DeviceId, EventsLoop, Icon, MonitorId, Window, WindowBuilder};
+use platform::EventsLoop as WindowsEventsLoop;
+
+/// Additional methods on `EventsLoop` that are specific to Windows.
+pub trait EventsLoopExt {
+    /// By default, winit on Windows will attempt to enable process-wide DPI awareness. If that's
+    /// undesirable, you can create an `EventsLoop` using this function instead.
+    fn new_dpi_unaware() -> Self where Self: Sized;
+}
+
+impl EventsLoopExt for EventsLoop {
+    #[inline]
+    fn new_dpi_unaware() -> Self {
+        EventsLoop {
+            events_loop: WindowsEventsLoop::with_dpi_awareness(false),
+            _marker: ::std::marker::PhantomData,
+        }
+    }
+}
 
 /// Additional methods on `Window` that are specific to Windows.
 pub trait WindowExt {

src/platform/android/mod.rs

@@ -2,24 +2,34 @@
 
 extern crate android_glue;
 
-use libc;
-use std::sync::mpsc::{Receiver, channel};
+mod ffi;
+
+use std::cell::RefCell;
+use std::collections::VecDeque;
+use std::fmt;
 use std::os::raw::c_void;
-use {CreationError, Event, WindowEvent, MouseCursor};
+use std::sync::mpsc::{Receiver, channel};
+
+use {
+    CreationError,
+    CursorState,
+    Event,
+    LogicalPosition,
+    LogicalSize,
+    MouseCursor,
+    PhysicalPosition,
+    PhysicalSize,
+    WindowAttributes,
+    WindowEvent,
+    WindowId as RootWindowId,
+};
 use CreationError::OsError;
-use WindowId as RootWindowId;
 use events::{Touch, TouchPhase};
 use window::MonitorId as RootMonitorId;
 
-use std::collections::VecDeque;
-use std::cell::RefCell;
-
-use CursorState;
-use WindowAttributes;
-
 pub struct EventsLoop {
     event_rx: Receiver<android_glue::Event>,
-    suspend_callback: RefCell<Option<Box<Fn(bool) -> ()>>>
+    suspend_callback: RefCell<Option<Box<Fn(bool) -> ()>>>,
 }
 
 #[derive(Clone)]
@@ -31,13 +41,13 @@ impl EventsLoop {
         android_glue::add_sender(tx);
         EventsLoop {
             event_rx: rx,
-            suspend_callback: RefCell::new(None),
+            suspend_callback: Default::default(),
         }
     }
 
     #[inline]
     pub fn get_available_monitors(&self) -> VecDeque<MonitorId> {
-        let mut rb = VecDeque::new();
+        let mut rb = VecDeque::with_capacity(1);
         rb.push_back(MonitorId);
         rb
     }
@@ -47,14 +57,17 @@ impl EventsLoop {
         MonitorId
     }
 
-
     pub fn poll_events<F>(&mut self, mut callback: F)
         where F: FnMut(::Event)
     {
         while let Ok(event) = self.event_rx.try_recv() {
-
             let e = match event{
                 android_glue::Event::EventMotion(motion) => {
+                    let dpi_factor = MonitorId.get_hidpi_factor();
+                    let location = LogicalPosition::from_physical(
+                        (motion.x as f64, motion.y as f64),
+                        dpi_factor,
+                    );
                     Some(Event::WindowEvent {
                         window_id: RootWindowId(WindowId),
                         event: WindowEvent::Touch(Touch {
@@ -64,7 +77,7 @@ impl EventsLoop {
                                 android_glue::MotionAction::Up => TouchPhase::Ended,
                                 android_glue::MotionAction::Cancel => TouchPhase::Cancelled,
                             },
-                            location: (motion.x as f64, motion.y as f64),
+                            location,
                             id: motion.pointer_id as u64,
                             device_id: DEVICE_ID,
                         }),
@@ -91,11 +104,12 @@ impl EventsLoop {
                     if native_window.is_null() {
                         None
                     } else {
-                        let w = unsafe { ffi::ANativeWindow_getWidth(native_window as *const _) } as u32;
-                        let h = unsafe { ffi::ANativeWindow_getHeight(native_window as *const _) } as u32;
+                        let dpi_factor = MonitorId.get_hidpi_factor();
+                        let physical_size = MonitorId.get_dimensions();
+                        let size = LogicalSize::from_physical(physical_size, dpi_factor);
                         Some(Event::WindowEvent {
                             window_id: RootWindowId(WindowId),
-                            event: WindowEvent::Resized(w, h),
+                            event: WindowEvent::Resized(size),
                         })
                     }
                 },
@@ -164,10 +178,29 @@ pub struct Window {
     native_window: *const c_void,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Clone)]
 pub struct MonitorId;
 
-mod ffi;
+impl fmt::Debug for MonitorId {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        #[derive(Debug)]
+        struct MonitorId {
+            name: Option<String>,
+            dimensions: PhysicalSize,
+            position: PhysicalPosition,
+            hidpi_factor: f64,
+        }
+
+        let monitor_id_proxy = MonitorId {
+            name: self.get_name(),
+            dimensions: self.get_dimensions(),
+            position: self.get_position(),
+            hidpi_factor: self.get_hidpi_factor(),
+        };
+
+        monitor_id_proxy.fmt(f)
+    }
+}
 
 impl MonitorId {
     #[inline]
@@ -176,21 +209,24 @@ impl MonitorId {
     }
 
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
+    pub fn get_dimensions(&self) -> PhysicalSize {
         unsafe {
             let window = android_glue::get_native_window();
-            (ffi::ANativeWindow_getWidth(window) as u32, ffi::ANativeWindow_getHeight(window) as u32)
+            (
+                ffi::ANativeWindow_getWidth(window) as f64,
+                ffi::ANativeWindow_getHeight(window) as f64,
+            ).into()
         }
     }
 
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         // Android assumes single screen
-        (0, 0)
+        (0, 0).into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         1.0
     }
 }
@@ -205,10 +241,6 @@ impl Window {
                _: PlatformSpecificWindowBuilderAttributes)
                -> Result<Window, CreationError>
     {
-        // not implemented
-        assert!(win_attribs.min_dimensions.is_none());
-        assert!(win_attribs.max_dimensions.is_none());
-
         let native_window = unsafe { android_glue::get_native_window() };
         if native_window.is_null() {
             return Err(OsError(format!("Android's native window is null")));
@@ -228,98 +260,103 @@ impl Window {
 
     #[inline]
     pub fn set_title(&self, _: &str) {
+        // N/A
     }
 
     #[inline]
     pub fn show(&self) {
+        // N/A
     }
 
     #[inline]
     pub fn hide(&self) {
+        // N/A
     }
 
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
+        // N/A
         None
     }
 
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
+        // N/A
         None
     }
 
     #[inline]
-    pub fn set_position(&self, _x: i32, _y: i32) {
+    pub fn set_position(&self, _position: LogicalPosition) {
+        // N/A
     }
 
     #[inline]
-    pub fn set_min_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
+    pub fn set_min_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
 
     #[inline]
-    pub fn set_max_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
+    pub fn set_max_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
 
     #[inline]
     pub fn set_resizable(&self, _resizable: bool) {
         // N/A
     }
-    
+
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
         if self.native_window.is_null() {
             None
         } else {
-            Some((
-                unsafe { ffi::ANativeWindow_getWidth(self.native_window as *const _) } as u32,
-                unsafe { ffi::ANativeWindow_getHeight(self.native_window as *const _) } as u32
-            ))
+            let dpi_factor = self.get_hidpi_factor();
+            let physical_size = self.get_current_monitor().get_dimensions();
+            Some(LogicalSize::from_physical(physical_size, dpi_factor))
         }
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         self.get_inner_size()
     }
 
     #[inline]
-    pub fn set_inner_size(&self, _x: u32, _y: u32) {
+    pub fn set_inner_size(&self, _size: LogicalSize) {
+        // N/A
     }
 
     #[inline]
-    pub fn platform_display(&self) -> *mut libc::c_void {
-        unimplemented!();
-    }
-
-    #[inline]
-    pub fn platform_window(&self) -> *mut libc::c_void {
-        unimplemented!()
+    pub fn get_hidpi_factor(&self) -> f64 {
+        self.get_current_monitor().get_hidpi_factor()
     }
 
     #[inline]
     pub fn set_cursor(&self, _: MouseCursor) {
+        // N/A
     }
 
     #[inline]
     pub fn set_cursor_state(&self, _state: CursorState) -> Result<(), String> {
+        // N/A
         Ok(())
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
-        1.0
-    }
-
-    #[inline]
-    pub fn set_cursor_position(&self, _x: i32, _y: i32) -> Result<(), ()> {
+    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ()> {
+        // N/A
         Ok(())
     }
 
     #[inline]
     pub fn set_maximized(&self, _maximized: bool) {
+        // N/A
         // Android has single screen maximized apps so nothing to do
     }
 
     #[inline]
     pub fn set_fullscreen(&self, _monitor: Option<RootMonitorId>) {
+        // N/A
         // Android has single screen maximized apps so nothing to do
     }
 
@@ -339,15 +376,16 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+    pub fn set_ime_spot(&self, _spot: LogicalPosition) {
         // N/A
     }
 
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
-        RootMonitorId{inner: MonitorId}
+        RootMonitorId { inner: MonitorId }
     }
 
+    #[inline]
     pub fn id(&self) -> WindowId {
         WindowId
     }

src/platform/emscripten/ffi.rs

@@ -1,6 +1,4 @@
-#![allow(dead_code)]
-#![allow(non_snake_case)]
-#![allow(non_camel_case_types)]
+#![allow(dead_code, non_camel_case_types, non_snake_case)]
 
 use std::os::raw::{c_int, c_char, c_void, c_ulong, c_double, c_long, c_ushort};
 #[cfg(test)]

src/platform/emscripten/mod.rs

@@ -2,16 +2,21 @@
 
 mod ffi;
 
-use std::mem;
-use std::os::raw::{c_char, c_void, c_double, c_ulong, c_int};
-use std::ptr;
-use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::{Mutex, Arc};
+use std::{mem, ptr, str};
 use std::cell::RefCell;
 use std::collections::VecDeque;
+use std::os::raw::{c_char, c_void, c_double, c_ulong, c_int};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Mutex, Arc};
+
+use {LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize};
 
 const DOCUMENT_NAME: &'static str = "#document\0";
 
+fn get_hidpi_factor() -> f64 {
+    unsafe { ffi::emscripten_get_device_pixel_ratio() as f64 }
+}
+
 #[derive(Clone, Default)]
 pub struct PlatformSpecificWindowBuilderAttributes;
 
@@ -34,18 +39,18 @@ impl MonitorId {
     }
 
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         unimplemented!()
     }
 
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
-        (0, 0)
+    pub fn get_dimensions(&self) -> PhysicalSize {
+        (0, 0).into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
-        1.0
+    pub fn get_hidpi_factor(&self) -> f64 {
+        get_hidpi_factor()
     }
 }
 
@@ -90,17 +95,19 @@ impl EventsLoop {
         }
     }
 
+    #[inline]
     pub fn interrupt(&self) {
         self.interrupted.store(true, Ordering::Relaxed);
     }
 
+    #[inline]
     pub fn create_proxy(&self) -> EventsLoopProxy {
         unimplemented!()
     }
 
     #[inline]
     pub fn get_available_monitors(&self) -> VecDeque<MonitorId> {
-        let mut list = VecDeque::new();
+        let mut list = VecDeque::with_capacity(1);
         list.push_back(MonitorId);
         list
     }
@@ -115,7 +122,7 @@ impl EventsLoop {
     {
         let ref mut window = *self.window.lock().unwrap();
         if let &mut Some(ref mut window) = window {
-            while let Some(event) = window.events.borrow_mut().pop_front() {
+            while let Some(event) = window.events.lock().unwrap().pop_front() {
                 callback(event)
             }
         }
@@ -144,7 +151,7 @@ pub struct WindowId(usize);
 pub struct Window2 {
     cursor_state: Mutex<::CursorState>,
     is_fullscreen: bool,
-    events: Box<RefCell<VecDeque<::Event>>>,
+    events: Box<Mutex<VecDeque<::Event>>>,
 }
 
 pub struct Window {
@@ -176,7 +183,7 @@ extern "C" fn mouse_callback(
     event_queue: *mut c_void) -> ffi::EM_BOOL
 {
     unsafe {
-        let queue: &RefCell<VecDeque<::Event>> = mem::transmute(event_queue);
+        let queue: &Mutex<VecDeque<::Event>> = mem::transmute(event_queue);
 
         let modifiers = ::ModifiersState {
             shift: (*event).shiftKey == ffi::EM_TRUE,
@@ -187,15 +194,20 @@ extern "C" fn mouse_callback(
 
         match event_type {
             ffi::EMSCRIPTEN_EVENT_MOUSEMOVE => {
-                queue.borrow_mut().push_back(::Event::WindowEvent {
+                let dpi_factor = get_hidpi_factor();
+                let position = LogicalPosition::from_physical(
+                    ((*event).canvasX as f64, (*event).canvasY as f64),
+                    dpi_factor,
+                );
+                queue.lock().unwrap().push_back(::Event::WindowEvent {
                     window_id: ::WindowId(WindowId(0)),
                     event: ::WindowEvent::CursorMoved {
                         device_id: ::DeviceId(DeviceId),
-                        position: ((*event).canvasX as f64, (*event).canvasY as f64),
+                        position,
                         modifiers: modifiers,
                     }
                 });
-                queue.borrow_mut().push_back(::Event::DeviceEvent {
+                queue.lock().unwrap().push_back(::Event::DeviceEvent {
                     device_id: ::DeviceId(DeviceId),
                     event: ::DeviceEvent::MouseMotion {
                         delta: ((*event).movementX as f64, (*event).movementY as f64),
@@ -215,7 +227,7 @@ extern "C" fn mouse_callback(
                     ffi::EMSCRIPTEN_EVENT_MOUSEUP => ::ElementState::Released,
                     _ => unreachable!(),
                 };
-                queue.borrow_mut().push_back(::Event::WindowEvent {
+                queue.lock().unwrap().push_back(::Event::WindowEvent {
                     window_id: ::WindowId(WindowId(0)),
                     event: ::WindowEvent::MouseInput {
                         device_id: ::DeviceId(DeviceId),
@@ -238,7 +250,7 @@ extern "C" fn keyboard_callback(
     event_queue: *mut c_void) -> ffi::EM_BOOL
 {
     unsafe {
-        let queue: &RefCell<VecDeque<::Event>> = mem::transmute(event_queue);
+        let queue: &Mutex<VecDeque<::Event>> = mem::transmute(event_queue);
 
         let modifiers = ::ModifiersState {
             shift: (*event).shiftKey == ffi::EM_TRUE,
@@ -249,7 +261,7 @@ extern "C" fn keyboard_callback(
 
         match event_type {
             ffi::EMSCRIPTEN_EVENT_KEYDOWN => {
-                queue.borrow_mut().push_back(::Event::WindowEvent {
+                queue.lock().unwrap().push_back(::Event::WindowEvent {
                     window_id: ::WindowId(WindowId(0)),
                     event: ::WindowEvent::KeyboardInput {
                         device_id: ::DeviceId(DeviceId),
@@ -263,7 +275,7 @@ extern "C" fn keyboard_callback(
                 });
             },
             ffi::EMSCRIPTEN_EVENT_KEYUP => {
-                queue.borrow_mut().push_back(::Event::WindowEvent {
+                queue.lock().unwrap().push_back(::Event::WindowEvent {
                     window_id: ::WindowId(WindowId(0)),
                     event: ::WindowEvent::KeyboardInput {
                         device_id: ::DeviceId(DeviceId),
@@ -289,7 +301,7 @@ extern fn touch_callback(
     event_queue: *mut c_void) -> ffi::EM_BOOL
 {
     unsafe {
-        let queue: &RefCell<VecDeque<::Event>> = mem::transmute(event_queue);
+        let queue: &Mutex<VecDeque<::Event>> = mem::transmute(event_queue);
 
         let phase = match event_type {
             ffi::EMSCRIPTEN_EVENT_TOUCHSTART => ::TouchPhase::Started,
@@ -302,13 +314,18 @@ extern fn touch_callback(
         for touch in 0..(*event).numTouches as usize {
             let touch = (*event).touches[touch];
             if touch.isChanged == ffi::EM_TRUE {
-                queue.borrow_mut().push_back(::Event::WindowEvent {
+                let dpi_factor = get_hidpi_factor();
+                let location = LogicalPosition::from_physical(
+                    (touch.canvasX as f64, touch.canvasY as f64),
+                    dpi_factor,
+                );
+                queue.lock().unwrap().push_back(::Event::WindowEvent {
                     window_id: ::WindowId(WindowId(0)),
                     event: ::WindowEvent::Touch(::Touch {
                         device_id: ::DeviceId(DeviceId),
                         phase,
                         id: touch.identifier as u64,
-                        location: (touch.canvasX as f64, touch.canvasY as f64),
+                        location,
                     }),
                 });
             }
@@ -356,8 +373,8 @@ impl Window {
         }
 
         let w = Window2 {
-            cursor_state: Mutex::new(::CursorState::Normal),
-            events: Box::new(RefCell::new(VecDeque::new())),
+            cursor_state: Default::default(),
+            events: Default::default(),
             is_fullscreen: attribs.fullscreen.is_some(),
         };
 
@@ -395,8 +412,8 @@ impl Window {
                 em_try(ffi::emscripten_set_fullscreenchange_callback(ptr::null(), 0 as *mut c_void, ffi::EM_FALSE, Some(fullscreen_callback)))
                     .map_err(|e| ::CreationError::OsError(e))?;
             }
-        } else if let Some((w, h)) = attribs.dimensions {
-            window.set_inner_size(w, h);
+        } else if let Some(size) = attribs.dimensions {
+            window.set_inner_size(size);
         }
 
         *events_loop.window.lock().unwrap() = Some(window.window.clone());
@@ -413,22 +430,22 @@ impl Window {
     }
 
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
-        Some((0, 0))
+    pub fn get_position(&self) -> Option<LogicalPosition> {
+        Some((0, 0).into())
     }
 
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
-        Some((0, 0))
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
+        Some((0, 0).into())
     }
 
     #[inline]
-    pub fn set_position(&self, _: i32, _: i32) {
+    pub fn set_position(&self, _: LogicalPosition) {
     }
 
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    #[inline]
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
         unsafe {
-            use std::{mem, ptr};
             let mut width = 0;
             let mut height = 0;
             let mut fullscreen = 0;
@@ -438,31 +455,42 @@ impl Window {
             {
                 None
             } else {
-                Some((width as u32, height as u32))
+                let dpi_factor = self.get_hidpi_factor();
+                let logical = LogicalSize::from_physical((width as u32, height as u32), dpi_factor);
+                Some(logical)
             }
         }
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         self.get_inner_size()
     }
 
     #[inline]
-    pub fn set_inner_size(&self, width: u32, height: u32) {
+    pub fn set_inner_size(&self, size: LogicalSize) {
         unsafe {
-            use std::ptr;
-            ffi::emscripten_set_element_css_size(ptr::null(), width as c_double, height
-                as c_double);
+            let dpi_factor = self.get_hidpi_factor();
+            let physical = PhysicalSize::from_logical(size, dpi_factor);
+            let (width, height): (u32, u32) = physical.into();
+            ffi::emscripten_set_element_css_size(
+                ptr::null(),
+                width as c_double,
+                height as c_double,
+            );
         }
     }
 
     #[inline]
-    pub fn set_min_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
+    pub fn set_min_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
 
     #[inline]
-    pub fn set_max_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
-    
+    pub fn set_max_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
+
     #[inline]
     pub fn set_resizable(&self, _resizable: bool) {
         // N/A
@@ -473,16 +501,6 @@ impl Window {
     #[inline]
     pub fn hide(&self) {}
 
-    #[inline]
-    pub fn platform_display(&self) -> *mut ::libc::c_void {
-        unimplemented!()
-    }
-
-    #[inline]
-    pub fn platform_window(&self) -> *mut ::libc::c_void {
-        unimplemented!()
-    }
-
     #[inline]
     pub fn set_cursor(&self, _cursor: ::MouseCursor) {}
 
@@ -524,12 +542,12 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
-        unsafe { ffi::emscripten_get_device_pixel_ratio() as f32 }
+    pub fn get_hidpi_factor(&self) -> f64 {
+        get_hidpi_factor()
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _x: i32, _y: i32) -> Result<(), ()> {
+    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ()> {
         Err(())
     }
 
@@ -559,7 +577,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+    pub fn set_ime_spot(&self, _logical_spot: LogicalPosition) {
         // N/A
     }
 
@@ -612,7 +630,6 @@ fn error_to_str(code: ffi::EMSCRIPTEN_RESULT) -> &'static str {
 }
 
 fn key_translate(input: [ffi::EM_UTF8; ffi::EM_HTML5_SHORT_STRING_LEN_BYTES]) -> u8 {
-    use std::str;
     let slice = &input[0..input.iter().take_while(|x| **x != 0).count()];
     let maybe_key = unsafe { str::from_utf8(mem::transmute::<_, &[u8]>(slice)) };
     let key = match maybe_key {
@@ -629,7 +646,6 @@ fn key_translate(input: [ffi::EM_UTF8; ffi::EM_HTML5_SHORT_STRING_LEN_BYTES]) ->
 fn key_translate_virt(input: [ffi::EM_UTF8; ffi::EM_HTML5_SHORT_STRING_LEN_BYTES],
                       location: c_ulong) -> Option<::VirtualKeyCode>
 {
-    use std::str;
     let slice = &input[0..input.iter().take_while(|x| **x != 0).count()];
     let maybe_key = unsafe { str::from_utf8(mem::transmute::<_, &[u8]>(slice)) };
     let key = match maybe_key {

src/platform/ios/ffi.rs

@@ -1,22 +1,23 @@
+#![allow(non_camel_case_types, non_snake_case, non_upper_case_globals)]
+
 use std::ffi::CString;
+use std::mem;
+use std::os::raw::*;
 
-use libc;
-use objc::runtime::{ Object, Class };
+use objc::runtime::{Class, Object};
 
-#[allow(non_camel_case_types)]
 pub type id = *mut Object;
-
-#[allow(non_camel_case_types)]
-#[allow(non_upper_case_globals)]
 pub const nil: id = 0 as id;
 
-pub type CFStringRef = *const libc::c_void;
+pub type CFStringRef = *const c_void;
 pub type CFTimeInterval = f64;
 pub type Boolean = u32;
 
-#[allow(non_upper_case_globals)]
 pub const kCFRunLoopRunHandledSource: i32 = 4;
 
+pub const UIViewAutoresizingFlexibleWidth: NSUInteger = 1 << 1;
+pub const UIViewAutoresizingFlexibleHeight: NSUInteger = 1 << 4;
+
 #[cfg(target_pointer_width = "32")]
 pub type CGFloat = f32;
 #[cfg(target_pointer_width = "64")]
@@ -38,14 +39,14 @@ pub struct CGPoint {
 #[derive(Debug, Clone)]
 pub struct CGRect {
     pub origin: CGPoint,
-    pub size: CGSize
+    pub size: CGSize,
 }
 
 #[repr(C)]
 #[derive(Debug, Clone)]
 pub struct CGSize {
     pub width: CGFloat,
-    pub height: CGFloat
+    pub height: CGFloat,
 }
 
 #[link(name = "UIKit", kind = "framework")]
@@ -55,15 +56,24 @@ extern {
     pub static kCFRunLoopDefaultMode: CFStringRef;
 
     // int UIApplicationMain ( int argc, char *argv[], NSString *principalClassName, NSString *delegateClassName );
-    pub fn UIApplicationMain(argc: libc::c_int, argv: *const libc::c_char, principalClassName: id, delegateClassName: id) -> libc::c_int;
+    pub fn UIApplicationMain(
+        argc: c_int,
+        argv: *const c_char,
+        principalClassName: id,
+        delegateClassName: id,
+    ) -> c_int;
 
     // SInt32 CFRunLoopRunInMode ( CFStringRef mode, CFTimeInterval seconds, Boolean returnAfterSourceHandled );
-    pub fn CFRunLoopRunInMode(mode: CFStringRef, seconds: CFTimeInterval, returnAfterSourceHandled: Boolean) -> i32;
+    pub fn CFRunLoopRunInMode(
+        mode: CFStringRef,
+        seconds: CFTimeInterval,
+        returnAfterSourceHandled: Boolean,
+    ) -> i32;
 }
 
 extern {
-    pub fn setjmp(env: *mut libc::c_void) -> libc::c_int;
-    pub fn longjmp(env: *mut libc::c_void, val: libc::c_int);
+    pub fn setjmp(env: *mut c_void) -> c_int;
+    pub fn longjmp(env: *mut c_void, val: c_int);
 }
 
 pub trait NSString: Sized {
@@ -71,17 +81,14 @@ pub trait NSString: Sized {
         msg_send![class("NSString"), alloc]
     }
 
-    #[allow(non_snake_case)]
-    unsafe fn initWithUTF8String_(self, c_string: *const i8) -> id;
-    #[allow(non_snake_case)]
+    unsafe fn initWithUTF8String_(self, c_string: *const c_char) -> id;
     unsafe fn stringByAppendingString_(self, other: id) -> id;
     unsafe fn init_str(self, string: &str) -> Self;
-    #[allow(non_snake_case)]
-    unsafe fn UTF8String(self) -> *const libc::c_char;
+    unsafe fn UTF8String(self) -> *const c_char;
 }
 
 impl NSString for id {
-    unsafe fn initWithUTF8String_(self, c_string: *const i8) -> id {
+    unsafe fn initWithUTF8String_(self, c_string: *const c_char) -> id {
         msg_send![self, initWithUTF8String:c_string as id]
     }
 
@@ -94,7 +101,7 @@ impl NSString for id {
         self.initWithUTF8String_(cstring.as_ptr())
     }
 
-    unsafe fn UTF8String(self) -> *const libc::c_char {
+    unsafe fn UTF8String(self) -> *const c_char {
         msg_send![self, UTF8String]
     }
 }
@@ -102,6 +109,6 @@ impl NSString for id {
 #[inline]
 pub fn class(name: &str) -> *mut Class {
     unsafe {
-        ::std::mem::transmute(Class::get(name))
+        mem::transmute(Class::get(name))
     }
 }

src/platform/ios/mod.rs

@@ -19,7 +19,7 @@
 //!
 //! ```rust, ignore
 //! #[no_mangle]
-//! pub extern fn start_glutin_app() {
+//! pub extern fn start_winit_app() {
 //!     start_inner()
 //! }
 //!
@@ -29,13 +29,13 @@
 //!
 //! ```
 //!
-//! Compile project and then drag resulting .a into Xcode project. Add glutin.h to xcode.
+//! Compile project and then drag resulting .a into Xcode project. Add winit.h to xcode.
 //!
 //! ```ignore
-//! void start_glutin_app();
+//! void start_winit_app();
 //! ```
 //!
-//! Use start_glutin_app inside your xcode's main function.
+//! Use start_winit_app inside your xcode's main function.
 //!
 //!
 //! # App lifecycle and events
@@ -45,7 +45,7 @@
 //! [app lifecycle](https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIApplicationDelegate_Protocol/).
 //!
 //!
-//! This is how those event are represented in glutin:
+//! This is how those event are represented in winit:
 //!
 //!  - applicationDidBecomeActive is Focused(true)
 //!  - applicationWillResignActive is Focused(false)
@@ -60,100 +60,147 @@
 
 #![cfg(target_os = "ios")]
 
+use std::{fmt, mem, ptr};
 use std::collections::VecDeque;
-use std::ptr;
-use std::mem;
-use std::os::raw::c_void;
+use std::os::raw::*;
 
-use libc;
-use libc::c_int;
-use objc::runtime::{Class, Object, Sel, BOOL, YES };
-use objc::declare::{ ClassDecl };
+use objc::declare::ClassDecl;
+use objc::runtime::{BOOL, Class, Object, Sel, YES};
 
-use { CreationError, CursorState, MouseCursor, WindowAttributes };
-use WindowId as RootEventId;
-use WindowEvent;
-use Event;
-use events::{ Touch, TouchPhase };
+use {
+    CreationError,
+    CursorState,
+    Event,
+    LogicalPosition,
+    LogicalSize,
+    MouseCursor,
+    PhysicalPosition,
+    PhysicalSize,
+    WindowAttributes,
+    WindowEvent,
+    WindowId as RootEventId,
+};
+use events::{Touch, TouchPhase};
 use window::MonitorId as RootMonitorId;
 
 mod ffi;
 use self::ffi::{
-    setjmp,
-    UIApplicationMain,
     CFTimeInterval,
     CFRunLoopRunInMode,
+    CGFloat,
+    CGPoint,
+    CGRect,
+    id,
     kCFRunLoopDefaultMode,
     kCFRunLoopRunHandledSource,
-    id,
+    longjmp,
     nil,
     NSString,
-    CGFloat,
-    longjmp,
-    CGRect,
-    CGPoint
+    setjmp,
+    UIApplicationMain,
+    UIViewAutoresizingFlexibleWidth,
+    UIViewAutoresizingFlexibleHeight,
  };
 
-static mut jmpbuf: [c_int;27] = [0;27];
-
-#[derive(Debug, Clone)]
-pub struct MonitorId;
+static mut JMPBUF: [c_int; 27] = [0; 27];
 
 pub struct Window {
-    delegate_state: *mut DelegateState
+    delegate_state: *mut DelegateState,
 }
 
-#[derive(Clone)]
-pub struct WindowProxy;
+unsafe impl Send for Window {}
+unsafe impl Sync for Window {}
 
 #[derive(Debug)]
 struct DelegateState {
     events_queue: VecDeque<Event>,
     window: id,
     controller: id,
-    size: (u32,u32),
-    scale: f32
+    view: id,
+    size: LogicalSize,
+    scale: f64,
 }
 
-
 impl DelegateState {
-    #[inline]
-    fn new(window: id, controller:id, size: (u32,u32), scale: f32) -> DelegateState {
+    fn new(window: id, controller: id, view: id, size: LogicalSize, scale: f64) -> DelegateState {
         DelegateState {
             events_queue: VecDeque::new(),
-            window: window,
-            controller: controller,
-            size: size,
-            scale: scale
+            window,
+            controller,
+            view,
+            size,
+            scale,
         }
     }
 }
 
+impl Drop for DelegateState {
+    fn drop(&mut self) {
+        unsafe {
+            let _: () = msg_send![self.window, release];
+            let _: () = msg_send![self.controller, release];
+            let _: () = msg_send![self.view, release];
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct MonitorId;
+
+impl fmt::Debug for MonitorId {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        #[derive(Debug)]
+        struct MonitorId {
+            name: Option<String>,
+            dimensions: PhysicalSize,
+            position: PhysicalPosition,
+            hidpi_factor: f64,
+        }
+
+        let monitor_id_proxy = MonitorId {
+            name: self.get_name(),
+            dimensions: self.get_dimensions(),
+            position: self.get_position(),
+            hidpi_factor: self.get_hidpi_factor(),
+        };
+
+        monitor_id_proxy.fmt(f)
+    }
+}
+
 impl MonitorId {
+    #[inline]
+    pub fn get_uiscreen(&self) -> id {
+        let class = Class::get("UIScreen").expect("Failed to get class `UIScreen`");
+        unsafe { msg_send![class, mainScreen] }
+    }
+
     #[inline]
     pub fn get_name(&self) -> Option<String> {
         Some("Primary".to_string())
     }
 
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
-        unimplemented!()
+    pub fn get_dimensions(&self) -> PhysicalSize {
+        let bounds: CGRect = unsafe { msg_send![self.get_uiscreen(), nativeBounds] };
+        (bounds.size.width as f64, bounds.size.height as f64).into()
     }
 
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         // iOS assumes single screen
-        (0, 0)
+        (0, 0).into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
-        1.0
+    pub fn get_hidpi_factor(&self) -> f64 {
+        let scale: CGFloat = unsafe { msg_send![self.get_uiscreen(), nativeScale] };
+        scale as f64
     }
 }
 
 pub struct EventsLoop {
-    delegate_state: *mut DelegateState
+    delegate_state: *mut DelegateState,
 }
 
 #[derive(Clone)]
@@ -162,30 +209,26 @@ pub struct EventsLoopProxy;
 impl EventsLoop {
     pub fn new() -> EventsLoop {
         unsafe {
-            if setjmp(mem::transmute(&mut jmpbuf)) != 0 {
-                let app: id = msg_send![Class::get("UIApplication").unwrap(), sharedApplication];
+            if setjmp(mem::transmute(&mut JMPBUF)) != 0 {
+                let app_class = Class::get("UIApplication").expect("Failed to get class `UIApplication`");
+                let app: id = msg_send![app_class, sharedApplication];
                 let delegate: id = msg_send![app, delegate];
-                let state: *mut c_void = *(&*delegate).get_ivar("glutinState");
-                let state = state as *mut DelegateState;
-
-                let events_loop = EventsLoop {
-                    delegate_state: state
-                };
-
-                return events_loop;
+                let state: *mut c_void = *(&*delegate).get_ivar("winitState");
+                let delegate_state = state as *mut DelegateState;
+                return EventsLoop { delegate_state };
             }
         }
 
-        create_delegate_class();
         create_view_class();
+        create_delegate_class();
         start_app();
 
-        panic!("Couldn't create UIApplication")
+        panic!("Couldn't create `UIApplication`!")
     }
 
     #[inline]
     pub fn get_available_monitors(&self) -> VecDeque<MonitorId> {
-        let mut rb = VecDeque::new();
+        let mut rb = VecDeque::with_capacity(1);
         rb.push_back(MonitorId);
         rb
     }
@@ -207,7 +250,7 @@ impl EventsLoop {
             }
 
             // jump hack, so we won't quit on willTerminate event before processing it
-            if setjmp(mem::transmute(&mut jmpbuf)) != 0 {
+            if setjmp(mem::transmute(&mut JMPBUF)) != 0 {
                 if let Some(event) = state.events_queue.pop_front() {
                     callback(event);
                     return;
@@ -262,111 +305,120 @@ pub struct DeviceId;
 #[derive(Clone, Default)]
 pub struct PlatformSpecificWindowBuilderAttributes;
 
+// TODO: AFAIK transparency is enabled by default on iOS,
+// so to be consistent with other platforms we have to change that.
 impl Window {
-    pub fn new(ev: &EventsLoop, _: WindowAttributes, _: PlatformSpecificWindowBuilderAttributes)
-               -> Result<Window, CreationError>
-    {
-        Ok(Window {
-            delegate_state: ev.delegate_state,
-        })
+    pub fn new(
+        ev: &EventsLoop,
+        _attributes: WindowAttributes,
+        _pl_alltributes: PlatformSpecificWindowBuilderAttributes,
+    ) -> Result<Window, CreationError> {
+        Ok(Window { delegate_state: ev.delegate_state })
     }
 
     #[inline]
-    pub fn set_title(&self, _: &str) {
+    pub fn get_uiwindow(&self) -> id {
+        unsafe { (*self.delegate_state).window }
+    }
+
+    #[inline]
+    pub fn get_uiview(&self) -> id {
+        unsafe { (*self.delegate_state).view }
+    }
+
+    #[inline]
+    pub fn set_title(&self, _title: &str) {
+        // N/A
     }
 
     #[inline]
     pub fn show(&self) {
+        // N/A
     }
 
     #[inline]
     pub fn hide(&self) {
+        // N/A
     }
 
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
+        // N/A
         None
     }
 
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
+        // N/A
         None
     }
 
     #[inline]
-    pub fn set_position(&self, _x: i32, _y: i32) {
+    pub fn set_position(&self, _position: LogicalPosition) {
+        // N/A
     }
 
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
         unsafe { Some((&*self.delegate_state).size) }
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         self.get_inner_size()
     }
 
     #[inline]
-    pub fn set_inner_size(&self, _x: u32, _y: u32) {
+    pub fn set_inner_size(&self, _size: LogicalSize) {
+        // N/A
     }
 
     #[inline]
-    pub fn set_min_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
+    pub fn set_min_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
 
     #[inline]
-    pub fn set_max_dimensions(&self, _dimensions: Option<(u32, u32)>) { }
+    pub fn set_max_dimensions(&self, _dimensions: Option<LogicalSize>) {
+        // N/A
+    }
 
     #[inline]
     pub fn set_resizable(&self, _resizable: bool) {
         // N/A
     }
-    
+
     #[inline]
-    pub fn platform_display(&self) -> *mut libc::c_void {
-        unimplemented!();
+    pub fn set_cursor(&self, _cursor: MouseCursor) {
+        // N/A
     }
 
     #[inline]
-    pub fn platform_window(&self) -> *mut libc::c_void {
-        unimplemented!()
-    }
-
-    #[inline]
-    pub fn set_window_resize_callback(&mut self, _: Option<fn(u32, u32)>) {
-    }
-
-    #[inline]
-    pub fn set_cursor(&self, _: MouseCursor) {
-    }
-
-    #[inline]
-    pub fn set_cursor_state(&self, _: CursorState) -> Result<(), String> {
+    pub fn set_cursor_state(&self, _cursor_state: CursorState) -> Result<(), String> {
+        // N/A
         Ok(())
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         unsafe { (&*self.delegate_state) }.scale
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _x: i32, _y: i32) -> Result<(), ()> {
-        unimplemented!();
-    }
-
-    #[inline]
-    pub fn create_window_proxy(&self) -> WindowProxy {
-        WindowProxy
+    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ()> {
+        // N/A
+        Ok(())
     }
 
     #[inline]
     pub fn set_maximized(&self, _maximized: bool) {
+        // N/A
         // iOS has single screen maximized apps so nothing to do
     }
 
     #[inline]
     pub fn set_fullscreen(&self, _monitor: Option<RootMonitorId>) {
+        // N/A
         // iOS has single screen maximized apps so nothing to do
     }
 
@@ -386,13 +438,13 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+    pub fn set_ime_spot(&self, _logical_spot: LogicalPosition) {
         // N/A
     }
 
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
-        RootMonitorId{inner: MonitorId}
+        RootMonitorId { inner: MonitorId }
     }
 
     #[inline]
@@ -403,26 +455,32 @@ impl Window {
 
 fn create_delegate_class() {
     extern fn did_finish_launching(this: &mut Object, _: Sel, _: id, _: id) -> BOOL {
+        let screen_class = Class::get("UIScreen").expect("Failed to get class `UIScreen`");
+        let window_class = Class::get("UIWindow").expect("Failed to get class `UIWindow`");
+        let controller_class = Class::get("MainViewController").expect("Failed to get class `MainViewController`");
+        let view_class = Class::get("MainView").expect("Failed to get class `MainView`");
         unsafe {
-            let main_screen: id = msg_send![Class::get("UIScreen").unwrap(), mainScreen];
+            let main_screen: id = msg_send![screen_class, mainScreen];
             let bounds: CGRect = msg_send![main_screen, bounds];
             let scale: CGFloat = msg_send![main_screen, nativeScale];
 
-            let window: id = msg_send![Class::get("UIWindow").unwrap(), alloc];
+            let window: id = msg_send![window_class, alloc];
             let window: id = msg_send![window, initWithFrame:bounds.clone()];
 
-            let size = (bounds.size.width as u32, bounds.size.height as u32);
+            let size = (bounds.size.width as f64, bounds.size.height as f64).into();
 
-            let view_controller: id = msg_send![Class::get("MainViewController").unwrap(), alloc];
+            let view_controller: id = msg_send![controller_class, alloc];
             let view_controller: id = msg_send![view_controller, init];
 
+            let view: id = msg_send![view_class, alloc];
+            let view: id = msg_send![view, initForGl:&bounds];
+
             let _: () = msg_send![window, setRootViewController:view_controller];
             let _: () = msg_send![window, makeKeyAndVisible];
 
-            let state = Box::new(DelegateState::new(window, view_controller, size, scale as f32));
+            let state = Box::new(DelegateState::new(window, view_controller, view, size, scale as f64));
             let state_ptr: *mut DelegateState = mem::transmute(state);
-            this.set_ivar("glutinState", state_ptr as *mut c_void);
-
+            this.set_ivar("winitState", state_ptr as *mut c_void);
 
             let _: () = msg_send![this, performSelector:sel!(postLaunch:) withObject:nil afterDelay:0.0];
         }
@@ -430,12 +488,12 @@ fn create_delegate_class() {
     }
 
     extern fn post_launch(_: &Object, _: Sel, _: id) {
-        unsafe { longjmp(mem::transmute(&mut jmpbuf),1); }
+        unsafe { longjmp(mem::transmute(&mut JMPBUF),1); }
     }
 
     extern fn did_become_active(this: &Object, _: Sel, _: id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
             state.events_queue.push_back(Event::WindowEvent {
                 window_id: RootEventId(WindowId),
@@ -446,7 +504,7 @@ fn create_delegate_class() {
 
     extern fn will_resign_active(this: &Object, _: Sel, _: id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
             state.events_queue.push_back(Event::WindowEvent {
                 window_id: RootEventId(WindowId),
@@ -457,7 +515,7 @@ fn create_delegate_class() {
 
     extern fn will_enter_foreground(this: &Object, _: Sel, _: id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
             state.events_queue.push_back(Event::Suspended(false));
         }
@@ -465,7 +523,7 @@ fn create_delegate_class() {
 
     extern fn did_enter_background(this: &Object, _: Sel, _: id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
             state.events_queue.push_back(Event::Suspended(true));
         }
@@ -473,7 +531,7 @@ fn create_delegate_class() {
 
     extern fn will_terminate(this: &Object, _: Sel, _: id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
             // push event to the front to garantee that we'll process it
             // immidiatly after jump
@@ -481,13 +539,13 @@ fn create_delegate_class() {
                 window_id: RootEventId(WindowId),
                 event: WindowEvent::Destroyed,
             });
-            longjmp(mem::transmute(&mut jmpbuf),1);
+            longjmp(mem::transmute(&mut JMPBUF),1);
         }
     }
 
     extern fn handle_touches(this: &Object, _: Sel, touches: id, _:id) {
         unsafe {
-            let state: *mut c_void = *this.get_ivar("glutinState");
+            let state: *mut c_void = *this.get_ivar("winitState");
             let state = &mut *(state as *mut DelegateState);
 
             let touches_enum: id = msg_send![touches, objectEnumerator];
@@ -506,7 +564,7 @@ fn create_delegate_class() {
                     event: WindowEvent::Touch(Touch {
                         device_id: DEVICE_ID,
                         id: touch_id,
-                        location: (location.x as f64, location.y as f64),
+                        location: (location.x as f64, location.y as f64).into(),
                         phase: match phase {
                             0 => TouchPhase::Started,
                             1 => TouchPhase::Moved,
@@ -521,8 +579,8 @@ fn create_delegate_class() {
         }
     }
 
-    let ui_responder = Class::get("UIResponder").unwrap();
-    let mut decl = ClassDecl::new("AppDelegate", ui_responder).unwrap();
+    let ui_responder = Class::get("UIResponder").expect("Failed to get class `UIResponder`");
+    let mut decl = ClassDecl::new("AppDelegate", ui_responder).expect("Failed to declare class `AppDelegate`");
 
     unsafe {
         decl.add_method(sel!(application:didFinishLaunchingWithOptions:),
@@ -560,17 +618,45 @@ fn create_delegate_class() {
         decl.add_method(sel!(postLaunch:),
                         post_launch as extern fn(&Object, Sel, id));
 
-        decl.add_ivar::<*mut c_void>("glutinState");
+        decl.add_ivar::<*mut c_void>("winitState");
 
         decl.register();
     }
 }
 
-fn create_view_class() {
-    let ui_view_controller = Class::get("UIViewController").unwrap();
-    let decl = ClassDecl::new("MainViewController", ui_view_controller).unwrap();
-
+// TODO: winit shouldn't contain GL-specfiic code
+pub fn create_view_class() {
+    let superclass = Class::get("UIViewController").expect("Failed to get class `UIViewController`");
+    let decl = ClassDecl::new("MainViewController", superclass).expect("Failed to declare class `MainViewController`");
     decl.register();
+
+    extern fn init_for_gl(this: &Object, _: Sel, frame: *const c_void) -> id {
+        unsafe {
+            let bounds = frame as *const CGRect;
+            let view: id = msg_send![this, initWithFrame:(*bounds).clone()];
+
+            let mask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
+            let _: () = msg_send![view, setAutoresizingMask:mask];
+            let _: () = msg_send![view, setAutoresizesSubviews:YES];
+
+            let layer: id = msg_send![view, layer];
+            let _ : () = msg_send![layer, setOpaque:YES];
+
+            view
+        }
+    }
+
+    extern fn layer_class(_: &Class, _: Sel) -> *const Class {
+        unsafe { mem::transmute(Class::get("CAEAGLLayer").expect("Failed to get class `CAEAGLLayer`")) }
+    }
+
+    let superclass = Class::get("GLKView").expect("Failed to get class `GLKView`");
+    let mut decl = ClassDecl::new("MainView", superclass).expect("Failed to declare class `MainView`");
+    unsafe {
+        decl.add_method(sel!(initForGl:), init_for_gl as extern fn(&Object, Sel, *const c_void) -> id);
+        decl.add_class_method(sel!(layerClass), layer_class as extern fn(&Class, Sel) -> *const Class);
+        decl.register();
+    }
 }
 
 #[inline]

src/platform/linux/mod.rs

@@ -8,15 +8,16 @@ use std::sync::Arc;
 
 use sctk::reexports::client::ConnectError;
 
-// `std::os::raw::c_void` and `libc::c_void` are NOT interchangeable!
-use libc;
-
 use {
     CreationError,
     CursorState,
     EventsLoopClosed,
     Icon,
+    LogicalPosition,
+    LogicalSize,
     MouseCursor,
+    PhysicalPosition,
+    PhysicalSize,
     ControlFlow,
     WindowAttributes,
 };
@@ -57,19 +58,19 @@ thread_local!(
 
 pub enum Window {
     X(x11::Window),
-    Wayland(wayland::Window)
+    Wayland(wayland::Window),
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum WindowId {
     X(x11::WindowId),
-    Wayland(wayland::WindowId)
+    Wayland(wayland::WindowId),
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum DeviceId {
     X(x11::DeviceId),
-    Wayland(wayland::DeviceId)
+    Wayland(wayland::DeviceId),
 }
 
 #[derive(Debug, Clone)]
@@ -96,7 +97,7 @@ impl MonitorId {
     }
 
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
+    pub fn get_dimensions(&self) -> PhysicalSize {
         match self {
             &MonitorId::X(ref m) => m.get_dimensions(),
             &MonitorId::Wayland(ref m) => m.get_dimensions(),
@@ -104,7 +105,7 @@ impl MonitorId {
     }
 
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         match self {
             &MonitorId::X(ref m) => m.get_position(),
             &MonitorId::Wayland(ref m) => m.get_position(),
@@ -112,10 +113,10 @@ impl MonitorId {
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         match self {
             &MonitorId::X(ref m) => m.get_hidpi_factor(),
-            &MonitorId::Wayland(ref m) => m.get_hidpi_factor(),
+            &MonitorId::Wayland(ref m) => m.get_hidpi_factor() as f64,
         }
     }
 }
@@ -141,7 +142,7 @@ impl Window {
     pub fn id(&self) -> WindowId {
         match self {
             &Window::X(ref w) => WindowId::X(w.id()),
-            &Window::Wayland(ref w) => WindowId::Wayland(w.id())
+            &Window::Wayland(ref w) => WindowId::Wayland(w.id()),
         }
     }
 
@@ -149,7 +150,7 @@ impl Window {
     pub fn set_title(&self, title: &str) {
         match self {
             &Window::X(ref w) => w.set_title(title),
-            &Window::Wayland(ref w) => w.set_title(title)
+            &Window::Wayland(ref w) => w.set_title(title),
         }
     }
 
@@ -157,7 +158,7 @@ impl Window {
     pub fn show(&self) {
         match self {
             &Window::X(ref w) => w.show(),
-            &Window::Wayland(ref w) => w.show()
+            &Window::Wayland(ref w) => w.show(),
         }
     }
 
@@ -165,20 +166,20 @@ impl Window {
     pub fn hide(&self) {
         match self {
             &Window::X(ref w) => w.hide(),
-            &Window::Wayland(ref w) => w.hide()
+            &Window::Wayland(ref w) => w.hide(),
         }
     }
 
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
         match self {
             &Window::X(ref w) => w.get_position(),
-            &Window::Wayland(ref w) => w.get_position()
+            &Window::Wayland(ref w) => w.get_position(),
         }
     }
 
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
         match self {
             &Window::X(ref m) => m.get_inner_position(),
             &Window::Wayland(ref m) => m.get_inner_position(),
@@ -186,53 +187,53 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_position(&self, x: i32, y: i32) {
+    pub fn set_position(&self, position: LogicalPosition) {
         match self {
-            &Window::X(ref w) => w.set_position(x, y),
-            &Window::Wayland(ref w) => w.set_position(x, y)
+            &Window::X(ref w) => w.set_position(position),
+            &Window::Wayland(ref w) => w.set_position(position),
         }
     }
 
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
         match self {
             &Window::X(ref w) => w.get_inner_size(),
-            &Window::Wayland(ref w) => w.get_inner_size()
+            &Window::Wayland(ref w) => w.get_inner_size(),
         }
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         match self {
             &Window::X(ref w) => w.get_outer_size(),
-            &Window::Wayland(ref w) => w.get_outer_size()
+            &Window::Wayland(ref w) => w.get_outer_size(),
         }
     }
 
     #[inline]
-    pub fn set_inner_size(&self, x: u32, y: u32) {
+    pub fn set_inner_size(&self, size: LogicalSize) {
         match self {
-            &Window::X(ref w) => w.set_inner_size(x, y),
-            &Window::Wayland(ref w) => w.set_inner_size(x, y)
+            &Window::X(ref w) => w.set_inner_size(size),
+            &Window::Wayland(ref w) => w.set_inner_size(size),
         }
     }
 
     #[inline]
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_min_dimensions(&self, dimensions: Option<LogicalSize>) {
         match self {
             &Window::X(ref w) => w.set_min_dimensions(dimensions),
-            &Window::Wayland(ref w) => w.set_min_dimensions(dimensions)
+            &Window::Wayland(ref w) => w.set_min_dimensions(dimensions),
         }
     }
 
     #[inline]
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_max_dimensions(&self, dimensions: Option<LogicalSize>) {
         match self {
             &Window::X(ref w) => w.set_max_dimensions(dimensions),
-            &Window::Wayland(ref w) => w.set_max_dimensions(dimensions)
+            &Window::Wayland(ref w) => w.set_max_dimensions(dimensions),
         }
     }
-    
+
     #[inline]
     pub fn set_resizable(&self, resizable: bool) {
         match self {
@@ -258,34 +259,18 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
        match self {
-            &Window::X(ref w) => w.hidpi_factor(),
-            &Window::Wayland(ref w) => w.hidpi_factor()
+            &Window::X(ref w) => w.get_hidpi_factor(),
+            &Window::Wayland(ref w) => w.hidpi_factor() as f64,
         }
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, x: i32, y: i32) -> Result<(), ()> {
+    pub fn set_cursor_position(&self, position: LogicalPosition) -> Result<(), ()> {
         match self {
-            &Window::X(ref w) => w.set_cursor_position(x, y),
-            &Window::Wayland(ref w) => w.set_cursor_position(x, y)
-        }
-    }
-
-    #[inline]
-    pub fn platform_display(&self) -> *mut libc::c_void {
-        match self {
-            &Window::X(ref w) => w.platform_display(),
-            &Window::Wayland(ref w) => w.get_display().c_ptr() as *mut _
-        }
-    }
-
-    #[inline]
-    pub fn platform_window(&self) -> *mut libc::c_void {
-        match self {
-            &Window::X(ref w) => w.platform_window(),
-            &Window::Wayland(ref w) => w.get_surface().c_ptr() as *mut _
+            &Window::X(ref w) => w.set_cursor_position(position),
+            &Window::Wayland(ref w) => w.set_cursor_position(position),
         }
     }
 
@@ -330,9 +315,9 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, x: i32, y: i32) {
+    pub fn set_ime_spot(&self, position: LogicalPosition) {
         match self {
-            &Window::X(ref w) => w.send_xim_spot(x as i16, y as i16),
+            &Window::X(ref w) => w.set_ime_spot(position),
             &Window::Wayland(_) => (),
         }
     }
@@ -447,14 +432,17 @@ r#"Failed to initialize any backend!
     #[inline]
     pub fn get_available_monitors(&self) -> VecDeque<MonitorId> {
         match *self {
-            EventsLoop::Wayland(ref evlp) => evlp.get_available_monitors()
-                                    .into_iter()
-                                    .map(MonitorId::Wayland)
-                                    .collect(),
-            EventsLoop::X(ref evlp) => x11::get_available_monitors(evlp.x_connection())
-                                        .into_iter()
-                                        .map(MonitorId::X)
-                                        .collect(),
+            EventsLoop::Wayland(ref evlp) => evlp
+                .get_available_monitors()
+                .into_iter()
+                .map(MonitorId::Wayland)
+                .collect(),
+            EventsLoop::X(ref evlp) => evlp
+                .x_connection()
+                .get_available_monitors()
+                .into_iter()
+                .map(MonitorId::X)
+                .collect(),
         }
     }
 
@@ -462,7 +450,7 @@ r#"Failed to initialize any backend!
     pub fn get_primary_monitor(&self) -> MonitorId {
         match *self {
             EventsLoop::Wayland(ref evlp) => MonitorId::Wayland(evlp.get_primary_monitor()),
-            EventsLoop::X(ref evlp) => MonitorId::X(x11::get_primary_monitor(evlp.x_connection())),
+            EventsLoop::X(ref evlp) => MonitorId::X(evlp.x_connection().get_primary_monitor()),
         }
     }
 

src/platform/linux/wayland/event_loop.rs

@@ -4,7 +4,7 @@ use std::fmt;
 use std::sync::{Arc, Mutex, Weak};
 use std::sync::atomic::{AtomicBool, Ordering};
 
-use {ControlFlow, EventsLoopClosed};
+use {ControlFlow, EventsLoopClosed, PhysicalPosition, PhysicalSize};
 
 use super::WindowId;
 use super::window::WindowStore;
@@ -248,16 +248,21 @@ impl EventsLoop {
         }
         // process pending resize/refresh
         self.store.lock().unwrap().for_each(
-            |newsize, refresh, frame_refresh, closed, wid, frame| {
+            |newsize, size, new_dpi, refresh, frame_refresh, closed, wid, frame| {
                 if let Some(frame) = frame {
                     if let Some((w, h)) = newsize {
-                        frame.resize(w as u32, h as u32);
+                        frame.resize(w, h);
                         frame.refresh();
-                        sink.send_event(::WindowEvent::Resized(w as u32, h as u32), wid);
+                        let logical_size = ::LogicalSize::new(w as f64, h as f64);
+                        sink.send_event(::WindowEvent::Resized(logical_size), wid);
+                        *size = (w, h);
                     } else if frame_refresh {
                         frame.refresh();
                     }
                 }
+                if let Some(dpi) = new_dpi {
+                    sink.send_event(::WindowEvent::HiDpiFactorChanged(dpi as f64), wid);
+                }
                 if refresh {
                     sink.send_event(::WindowEvent::Refresh, wid);
                 }
@@ -434,9 +439,9 @@ impl fmt::Debug for MonitorId {
         struct MonitorId {
             name: Option<String>,
             native_identifier: u32,
-            dimensions: (u32, u32),
-            position: (i32, i32),
-            hidpi_factor: f32,
+            dimensions: PhysicalSize,
+            position: PhysicalPosition,
+            hidpi_factor: i32,
         }
 
         let monitor_id_proxy = MonitorId {
@@ -463,7 +468,7 @@ impl MonitorId {
         self.mgr.with_info(&self.proxy, |id, _| id).unwrap_or(0)
     }
 
-    pub fn get_dimensions(&self) -> (u32, u32) {
+    pub fn get_dimensions(&self) -> PhysicalSize {
         match self.mgr.with_info(&self.proxy, |_, info| {
             info.modes
                 .iter()
@@ -472,19 +477,20 @@ impl MonitorId {
         }) {
             Some(Some((w, h))) => (w as u32, h as u32),
             _ => (0, 0),
-        }
+        }.into()
     }
 
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         self.mgr
             .with_info(&self.proxy, |_, info| info.location)
             .unwrap_or((0, 0))
+            .into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> i32 {
         self.mgr
-            .with_info(&self.proxy, |_, info| info.scale_factor as f32)
-            .unwrap_or(1.0)
+            .with_info(&self.proxy, |_, info| info.scale_factor)
+            .unwrap_or(1)
     }
 }

src/platform/linux/wayland/pointer.rs

@@ -42,7 +42,7 @@ pub fn implement_pointer(
                     sink.send_event(
                         WindowEvent::CursorMoved {
                             device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
-                            position: (surface_x, surface_y),
+                            position: (surface_x, surface_y).into(),
                             // TODO: replace dummy value with actual modifier state
                             modifiers: ModifiersState::default(),
                         },
@@ -71,7 +71,7 @@ pub fn implement_pointer(
                     sink.send_event(
                         WindowEvent::CursorMoved {
                             device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
-                            position: (surface_x, surface_y),
+                            position: (surface_x, surface_y).into(),
                             // TODO: replace dummy value with actual modifier state
                             modifiers: ModifiersState::default(),
                         },
@@ -117,7 +117,7 @@ pub fn implement_pointer(
                         sink.send_event(
                             WindowEvent::MouseWheel {
                                 device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
-                                delta: MouseScrollDelta::PixelDelta(x as f32, y as f32),
+                                delta: MouseScrollDelta::PixelDelta((x as f64, y as f64).into()),
                                 phase: TouchPhase::Moved,
                                 // TODO: replace dummy value with actual modifier state
                                 modifiers: ModifiersState::default(),
@@ -158,7 +158,7 @@ pub fn implement_pointer(
                         sink.send_event(
                             WindowEvent::MouseWheel {
                                 device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
-                                delta: MouseScrollDelta::PixelDelta(x as f32, y as f32),
+                                delta: MouseScrollDelta::PixelDelta((x as f64, y as f64).into()),
                                 phase: axis_state,
                                 // TODO: replace dummy value with actual modifier state
                                 modifiers: ModifiersState::default(),

src/platform/linux/wayland/touch.rs

@@ -34,7 +34,7 @@ pub(crate) fn implement_touch(
                         WindowEvent::Touch(::Touch {
                             device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
                             phase: TouchPhase::Started,
-                            location: (x, y),
+                            location: (x, y).into(),
                             id: id as u64,
                         }),
                         wid,
@@ -54,7 +54,7 @@ pub(crate) fn implement_touch(
                         WindowEvent::Touch(::Touch {
                             device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
                             phase: TouchPhase::Ended,
-                            location: pt.location,
+                            location: pt.location.into(),
                             id: id as u64,
                         }),
                         pt.wid,
@@ -69,7 +69,7 @@ pub(crate) fn implement_touch(
                         WindowEvent::Touch(::Touch {
                             device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
                             phase: TouchPhase::Moved,
-                            location: (x, y),
+                            location: (x, y).into(),
                             id: id as u64,
                         }),
                         pt.wid,
@@ -82,7 +82,7 @@ pub(crate) fn implement_touch(
                     WindowEvent::Touch(::Touch {
                         device_id: ::DeviceId(::platform::DeviceId::Wayland(DeviceId)),
                         phase: TouchPhase::Cancelled,
-                        location: pt.location,
+                        location: pt.location.into(),
                         id: pt.id as u64,
                     }),
                     pt.wid,

src/platform/linux/wayland/window.rs

@@ -1,12 +1,12 @@
 use std::sync::{Arc, Mutex, Weak};
 
-use {CreationError, CursorState, MouseCursor, WindowAttributes};
+use {CreationError, CursorState, MouseCursor, WindowAttributes, LogicalPosition, LogicalSize};
 use platform::MonitorId as PlatformMonitorId;
 use window::MonitorId as RootMonitorId;
 
 use sctk::window::{BasicFrame, Event as WEvent, Window as SWindow};
 use sctk::reexports::client::{Display, Proxy};
-use sctk::reexports::client::protocol::{wl_seat, wl_surface};
+use sctk::reexports::client::protocol::{wl_seat, wl_surface, wl_output};
 use sctk::reexports::client::protocol::wl_compositor::RequestsTrait as CompositorRequests;
 use sctk::reexports::client::protocol::wl_surface::RequestsTrait as SurfaceRequests;
 
@@ -15,7 +15,7 @@ use super::{make_wid, EventsLoop, MonitorId, WindowId};
 pub struct Window {
     surface: Proxy<wl_surface::WlSurface>,
     frame: Arc<Mutex<SWindow<BasicFrame>>>,
-    monitors: Arc<Mutex<Vec<MonitorId>>>,
+    monitors: Arc<Mutex<MonitorList>>,
     size: Arc<Mutex<(u32, u32)>>,
     kill_switch: (Arc<Mutex<bool>>, Arc<Mutex<bool>>),
     display: Arc<Display>,
@@ -24,23 +24,42 @@ pub struct Window {
 
 impl Window {
     pub fn new(evlp: &EventsLoop, attributes: WindowAttributes) -> Result<Window, CreationError> {
-        let (width, height) = attributes.dimensions.unwrap_or((800, 600));
+        // TODO: Update for new DPI API
+        //let (width, height) = attributes.dimensions.unwrap_or((800, 600));
+        let (width, height) = (64, 64);
         // Create the window
         let size = Arc::new(Mutex::new((width, height)));
 
         // monitor tracking
-        let monitor_list = Arc::new(Mutex::new(Vec::new()));
+        let monitor_list = Arc::new(Mutex::new(MonitorList::new()));
 
         let surface = evlp.env.compositor.create_surface().unwrap().implement({
             let list = monitor_list.clone();
             let omgr = evlp.env.outputs.clone();
-            move |event, _| match event {
-                wl_surface::Event::Enter { output } => list.lock().unwrap().push(MonitorId {
-                    proxy: output,
-                    mgr: omgr.clone(),
-                }),
+            let window_store = evlp.store.clone();
+            move |event, surface: Proxy<wl_surface::WlSurface>| match event {
+                wl_surface::Event::Enter { output } => {
+                    let dpi_change = list.lock().unwrap().add_output(MonitorId {
+                        proxy: output,
+                        mgr: omgr.clone(),
+                    });
+                    if let Some(dpi) = dpi_change {
+                        if surface.version() >= 3 {
+                            // without version 3 we can't be dpi aware
+                            window_store.lock().unwrap().dpi_change(&surface, dpi);
+                            surface.set_buffer_scale(dpi);
+                        }
+                    }
+                },
                 wl_surface::Event::Leave { output } => {
-                    list.lock().unwrap().retain(|m| !m.proxy.equals(&output));
+                    let dpi_change = list.lock().unwrap().del_output(&output);
+                    if let Some(dpi) = dpi_change {
+                        if surface.version() >= 3 {
+                            // without version 3 we can't be dpi aware
+                            window_store.lock().unwrap().dpi_change(&surface, dpi);
+                            surface.set_buffer_scale(dpi);
+                        }
+                    }
                 }
             }
         });
@@ -59,7 +78,7 @@ impl Window {
                     let mut store = window_store.lock().unwrap();
                     for window in &mut store.windows {
                         if window.surface.equals(&my_surface) {
-                            window.newsize = new_size.map(|(w, h)| (w as i32, h as i32));
+                            window.newsize = new_size;
                             window.need_refresh = true;
                             *(window.need_frame_refresh.lock().unwrap()) = true;
                             return;
@@ -107,8 +126,9 @@ impl Window {
         frame.set_decorate(attributes.decorations);
 
         // min-max dimensions
-        frame.set_min_size(attributes.min_dimensions);
-        frame.set_max_size(attributes.max_dimensions);
+        // TODO: Update for new DPI API
+        //frame.set_min_size(attributes.min_dimensions);
+        //frame.set_max_size(attributes.max_dimensions);
 
         let kill_switch = Arc::new(Mutex::new(false));
         let need_frame_refresh = Arc::new(Mutex::new(true));
@@ -117,11 +137,14 @@ impl Window {
         evlp.store.lock().unwrap().windows.push(InternalWindow {
             closed: false,
             newsize: None,
+            size: size.clone(),
             need_refresh: false,
             need_frame_refresh: need_frame_refresh.clone(),
             surface: surface.clone(),
             kill_switch: kill_switch.clone(),
             frame: Arc::downgrade(&frame),
+            current_dpi: 1,
+            new_dpi: None,
         });
         evlp.evq.borrow_mut().sync_roundtrip().unwrap();
 
@@ -156,48 +179,49 @@ impl Window {
     }
 
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
         // Not possible with wayland
         None
     }
 
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
         // Not possible with wayland
         None
     }
 
     #[inline]
-    pub fn set_position(&self, _x: i32, _y: i32) {
+    pub fn set_position(&self, _pos: LogicalPosition) {
         // Not possible with wayland
     }
 
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
-        Some(self.size.lock().unwrap().clone())
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
+        Some(self.size.lock().unwrap().clone().into())
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         let (w, h) = self.size.lock().unwrap().clone();
         // let (w, h) = super::wayland_window::add_borders(w as i32, h as i32);
-        Some((w as u32, h as u32))
+        Some((w, h).into())
     }
 
     #[inline]
     // NOTE: This will only resize the borders, the contents must be updated by the user
-    pub fn set_inner_size(&self, x: u32, y: u32) {
-        self.frame.lock().unwrap().resize(x, y);
-        *(self.size.lock().unwrap()) = (x, y);
+    pub fn set_inner_size(&self, size: LogicalSize) {
+        let (w, h) = size.into();
+        self.frame.lock().unwrap().resize(w, h);
+        *(self.size.lock().unwrap()) = (w, h);
     }
 
     #[inline]
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        self.frame.lock().unwrap().set_min_size(dimensions);
+    pub fn set_min_dimensions(&self, dimensions: Option<LogicalSize>) {
+        self.frame.lock().unwrap().set_min_size(dimensions.map(Into::into));
     }
 
     #[inline]
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        self.frame.lock().unwrap().set_max_size(dimensions);
+    pub fn set_max_dimensions(&self, dimensions: Option<LogicalSize>) {
+        self.frame.lock().unwrap().set_max_size(dimensions.map(Into::into));
     }
 
     #[inline]
@@ -222,14 +246,8 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
-        let mut factor: f32 = 1.0;
-        let guard = self.monitors.lock().unwrap();
-        for monitor_id in guard.iter() {
-            let hidpif = monitor_id.get_hidpi_factor();
-            factor = factor.max(hidpif);
-        }
-        factor
+    pub fn hidpi_factor(&self) -> i32 {
+        self.monitors.lock().unwrap().compute_hidpi_factor()
     }
 
     pub fn set_decorations(&self, decorate: bool) {
@@ -260,7 +278,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _x: i32, _y: i32) -> Result<(), ()> {
+    pub fn set_cursor_position(&self, _pos: LogicalPosition) -> Result<(), ()> {
         // TODO: not yet possible on wayland
         Err(())
     }
@@ -277,7 +295,7 @@ impl Window {
         // we don't know how much each monitor sees us so...
         // just return the most recent one ?
         let guard = self.monitors.lock().unwrap();
-        guard.last().unwrap().clone()
+        guard.monitors.last().unwrap().clone()
     }
 }
 
@@ -294,12 +312,15 @@ impl Drop for Window {
 
 struct InternalWindow {
     surface: Proxy<wl_surface::WlSurface>,
-    newsize: Option<(i32, i32)>,
+    newsize: Option<(u32, u32)>,
+    size: Arc<Mutex<(u32, u32)>>,
     need_refresh: bool,
     need_frame_refresh: Arc<Mutex<bool>>,
     closed: bool,
     kill_switch: Arc<Mutex<bool>>,
     frame: Weak<Mutex<SWindow<BasicFrame>>>,
+    current_dpi: i32,
+    new_dpi: Option<i32>
 }
 
 pub struct WindowStore {
@@ -345,24 +366,84 @@ impl WindowStore {
         }
     }
 
+    fn dpi_change(&mut self, surface: &Proxy<wl_surface::WlSurface>, new: i32) {
+        for window in &mut self.windows {
+            if surface.equals(&window.surface) {
+                window.new_dpi = Some(new);
+            }
+        }
+    }
+
     pub fn for_each<F>(&mut self, mut f: F)
     where
-        F: FnMut(Option<(i32, i32)>, bool, bool, bool, WindowId, Option<&mut SWindow<BasicFrame>>),
+        F: FnMut(Option<(u32, u32)>, &mut (u32, u32), Option<i32>, bool, bool, bool, WindowId, Option<&mut SWindow<BasicFrame>>),
     {
         for window in &mut self.windows {
             let opt_arc = window.frame.upgrade();
             let mut opt_mutex_lock = opt_arc.as_ref().map(|m| m.lock().unwrap());
             f(
                 window.newsize.take(),
+                &mut *(window.size.lock().unwrap()),
+                window.new_dpi,
                 window.need_refresh,
                 ::std::mem::replace(&mut *window.need_frame_refresh.lock().unwrap(), false),
                 window.closed,
                 make_wid(&window.surface),
                 opt_mutex_lock.as_mut().map(|m| &mut **m),
             );
+            if let Some(dpi) = window.new_dpi.take() {
+                window.current_dpi = dpi;
+            }
             window.need_refresh = false;
             // avoid re-spamming the event
             window.closed = false;
         }
     }
 }
+
+/*
+ * Monitor list with some covenience method to compute DPI
+ */
+
+struct MonitorList {
+    monitors: Vec<MonitorId>
+}
+
+impl MonitorList {
+    fn new() -> MonitorList {
+        MonitorList {
+            monitors: Vec::new()
+        }
+    }
+
+    fn compute_hidpi_factor(&self) -> i32 {
+        let mut factor = 1;
+        for monitor_id in &self.monitors {
+            let monitor_dpi = monitor_id.get_hidpi_factor();
+            if monitor_dpi > factor { factor = monitor_dpi; }
+        }
+        factor
+    }
+
+    fn add_output(&mut self, monitor: MonitorId) -> Option<i32> {
+        let old_dpi = self.compute_hidpi_factor();
+        let monitor_dpi = monitor.get_hidpi_factor();
+        self.monitors.push(monitor);
+        if monitor_dpi > old_dpi {
+            Some(monitor_dpi)
+        } else {
+            None
+        }
+    }
+
+    fn del_output(&mut self, output: &Proxy<wl_output::WlOutput>) -> Option<i32> {
+        let old_dpi = self.compute_hidpi_factor();
+        self.monitors.retain(|m| !m.proxy.equals(output));
+        let new_dpi = self.compute_hidpi_factor();
+        if new_dpi != old_dpi {
+            Some(new_dpi)
+        } else {
+            None
+        }
+    }
+}

src/platform/linux/x11/mod.rs

@@ -9,13 +9,7 @@ mod dnd;
 mod ime;
 pub mod util;
 
-pub use self::monitor::{
-    MonitorId,
-    get_available_monitors,
-    get_monitor_for_window,
-    get_primary_monitor,
-    invalidate_cached_monitor_list,
-};
+pub use self::monitor::MonitorId;
 pub use self::window::UnownedWindow;
 pub use self::xdisplay::{XConnection, XNotSupported, XError};
 
@@ -29,7 +23,6 @@ use std::sync::{Arc, mpsc, Weak};
 use std::sync::atomic::{self, AtomicBool};
 
 use libc::{self, setlocale, LC_CTYPE};
-use parking_lot::Mutex;
 
 use {
     ControlFlow,
@@ -38,6 +31,8 @@ use {
     Event,
     EventsLoopClosed,
     KeyboardInput,
+    LogicalPosition,
+    LogicalSize,
     WindowAttributes,
     WindowEvent,
 };
@@ -92,7 +87,7 @@ impl EventsLoop {
             result.expect("Failed to set input method destruction callback")
         });
 
-        let randr_event_offset = monitor::select_input(&xconn, root)
+        let randr_event_offset = xconn.select_xrandr_input(root)
             .expect("Failed to query XRandR extension");
 
         let xi2ext = unsafe {
@@ -394,6 +389,13 @@ impl EventsLoop {
             }
 
             ffi::ConfigureNotify => {
+                #[derive(Debug, Default)]
+                struct Events {
+                    resized: Option<WindowEvent>,
+                    moved: Option<WindowEvent>,
+                    dpi_changed: Option<WindowEvent>,
+                }
+
                 let xev: &ffi::XConfigureEvent = xev.as_ref();
                 let xwindow = xev.window;
                 let events = self.with_window(xwindow, |window| {
@@ -406,9 +408,11 @@ impl EventsLoop {
                     // that has a position relative to the parent window.
                     let is_synthetic = xev.send_event == ffi::True;
 
+                    // These are both in physical space.
                     let new_inner_size = (xev.width as u32, xev.height as u32);
                     let new_inner_position = (xev.x as i32, xev.y as i32);
 
+                    let monitor = window.get_current_monitor(); // This must be done *before* locking!
                     let mut shared_state_lock = window.shared_state.lock();
 
                     let (resized, moved) = {
@@ -431,14 +435,33 @@ impl EventsLoop {
                         (resized, moved)
                     };
 
-                    let capacity = resized as usize + moved as usize;
-                    let mut events = Vec::with_capacity(capacity);
-
-                    if resized {
-                        events.push(WindowEvent::Resized(new_inner_size.0, new_inner_size.1));
+                    // This is a hack to ensure that the DPI adjusted resize is actually applied on all WMs. KWin
+                    // doesn't need this, but Xfwm does.
+                    if let Some(adjusted_size) = shared_state_lock.dpi_adjusted {
+                        let rounded_size = (adjusted_size.0.round() as u32, adjusted_size.1.round() as u32);
+                        if new_inner_size == rounded_size {
+                            // When this finally happens, the event will not be synthetic.
+                            shared_state_lock.dpi_adjusted = None;
+                        } else {
+                            unsafe {
+                                (self.xconn.xlib.XResizeWindow)(
+                                    self.xconn.display,
+                                    xwindow,
+                                    rounded_size.0 as c_uint,
+                                    rounded_size.1 as c_uint,
+                                );
+                            }
+                        }
                     }
 
-                    if moved || shared_state_lock.position.is_none() {
+                    let mut events = Events::default();
+
+                    if resized {
+                        let logical_size = LogicalSize::from_physical(new_inner_size, monitor.hidpi_factor);
+                        events.resized = Some(WindowEvent::Resized(logical_size));
+                    }
+
+                    let new_outer_position = if moved || shared_state_lock.position.is_none() {
                         // We need to convert client area position to window position.
                         let frame_extents = shared_state_lock.frame_extents
                             .as_ref()
@@ -451,19 +474,59 @@ impl EventsLoop {
                         let outer = frame_extents.inner_pos_to_outer(new_inner_position.0, new_inner_position.1);
                         shared_state_lock.position = Some(outer);
                         if moved {
-                            events.push(WindowEvent::Moved(outer.0, outer.1));
+                            let logical_position = LogicalPosition::from_physical(outer, monitor.hidpi_factor);
+                            events.moved = Some(WindowEvent::Moved(logical_position));
                         }
+                        outer
+                    } else {
+                        shared_state_lock.position.unwrap()
+                    };
+
+                    // If we don't use the existing adjusted value when available, then the user can screw up the
+                    // resizing by dragging across monitors *without* dropping the window.
+                    let (width, height) = shared_state_lock.dpi_adjusted
+                        .unwrap_or_else(|| (xev.width as f64, xev.height as f64));
+                    let last_hidpi_factor = if shared_state_lock.is_new_window {
+                        shared_state_lock.is_new_window = false;
+                        1.0
+                    } else {
+                        shared_state_lock.last_monitor
+                            .as_ref()
+                            .map(|last_monitor| last_monitor.hidpi_factor)
+                            .unwrap_or(1.0)
+                    };
+                    let new_hidpi_factor = {
+                        let window_rect = util::Rect::new(new_outer_position, new_inner_size);
+                        let monitor = self.xconn.get_monitor_for_window(Some(window_rect));
+                        let new_hidpi_factor = monitor.hidpi_factor;
+                        shared_state_lock.last_monitor = Some(monitor);
+                        new_hidpi_factor
+                    };
+                    if last_hidpi_factor != new_hidpi_factor {
+                        events.dpi_changed = Some(WindowEvent::HiDpiFactorChanged(new_hidpi_factor));
+                        let (new_width, new_height, flusher) = window.adjust_for_dpi(
+                            last_hidpi_factor,
+                            new_hidpi_factor,
+                            width,
+                            height,
+                        );
+                        flusher.queue();
+                        shared_state_lock.dpi_adjusted = Some((new_width, new_height));
                     }
 
                     events
                 });
 
                 if let Some(events) = events {
-                    for event in events {
-                        callback(Event::WindowEvent {
-                            window_id: mkwid(xwindow),
-                            event,
-                        });
+                    let window_id = mkwid(xwindow);
+                    if let Some(event) = events.resized {
+                        callback(Event::WindowEvent { window_id, event });
+                    }
+                    if let Some(event) = events.moved {
+                        callback(Event::WindowEvent { window_id, event });
+                    }
+                    if let Some(event) = events.dpi_changed {
+                        callback(Event::WindowEvent { window_id, event });
                     }
                 }
             }
@@ -694,14 +757,25 @@ impl EventsLoop {
                             util::maybe_change(&mut shared_state_lock.cursor_pos, new_cursor_pos)
                         });
                         if cursor_moved == Some(true) {
-                            callback(Event::WindowEvent {
-                                window_id,
-                                event: CursorMoved {
-                                    device_id,
-                                    position: new_cursor_pos,
-                                    modifiers,
-                                },
+                            let dpi_factor = self.with_window(xev.event, |window| {
+                                window.get_hidpi_factor()
                             });
+                            if let Some(dpi_factor) = dpi_factor {
+                                let position = LogicalPosition::from_physical(
+                                    (xev.event_x as f64, xev.event_y as f64),
+                                    dpi_factor,
+                                );
+                                callback(Event::WindowEvent {
+                                    window_id,
+                                    event: CursorMoved {
+                                        device_id,
+                                        position,
+                                        modifiers,
+                                    },
+                                });
+                            } else {
+                                return;
+                            }
                         } else if cursor_moved.is_none() {
                             return;
                         }
@@ -782,19 +856,29 @@ impl EventsLoop {
                             event: CursorEntered { device_id },
                         });
 
-                        let new_cursor_pos = (xev.event_x, xev.event_y);
-
                         // The mods field on this event isn't actually populated, so query the
                         // pointer device. In the future, we can likely remove this round-trip by
                         // relying on Xkb for modifier values.
                         let modifiers = self.xconn.query_pointer(xev.event, xev.deviceid)
                             .expect("Failed to query pointer device").get_modifier_state();
 
-                        callback(Event::WindowEvent { window_id, event: CursorMoved {
-                            device_id,
-                            position: new_cursor_pos,
-                            modifiers,
-                        }})
+                        let dpi_factor = self.with_window(xev.event, |window| {
+                            window.get_hidpi_factor()
+                        });
+                        if let Some(dpi_factor) = dpi_factor {
+                            let position = LogicalPosition::from_physical(
+                                (xev.event_x as f64, xev.event_y as f64),
+                                dpi_factor,
+                            );
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: CursorMoved {
+                                    device_id,
+                                    position,
+                                    modifiers,
+                                },
+                            });
+                        }
                     }
                     ffi::XI_Leave => {
                         let xev: &ffi::XILeaveEvent = unsafe { &*(xev.data as *const _) };
@@ -812,7 +896,12 @@ impl EventsLoop {
                     ffi::XI_FocusIn => {
                         let xev: &ffi::XIFocusInEvent = unsafe { &*(xev.data as *const _) };
 
-                        if !self.window_exists(xev.event) { return; }
+                        let dpi_factor = match self.with_window(xev.event, |window| {
+                            window.get_hidpi_factor()
+                        }) {
+                            Some(dpi_factor) => dpi_factor,
+                            None => return,
+                        };
                         let window_id = mkwid(xev.event);
 
                         self.ime
@@ -830,11 +919,15 @@ impl EventsLoop {
                             .map(|device| device.attachment)
                             .unwrap_or(2);
 
+                        let position = LogicalPosition::from_physical(
+                            (xev.event_x as f64, xev.event_y as f64),
+                            dpi_factor,
+                        );
                         callback(Event::WindowEvent {
                             window_id,
                             event: CursorMoved {
                                 device_id: mkdid(pointer_id),
-                                position: (xev.event_x, xev.event_y),
+                                position,
                                 modifiers: ModifiersState::from(xev.mods),
                             }
                         });
@@ -861,15 +954,24 @@ impl EventsLoop {
                             ffi::XI_TouchEnd => TouchPhase::Ended,
                             _ => unreachable!()
                         };
-                        callback(Event::WindowEvent {
-                            window_id,
-                            event: WindowEvent::Touch(Touch {
-                                device_id: mkdid(xev.deviceid),
-                                phase,
-                                location: (xev.event_x, xev.event_y),
-                                id: xev.detail as u64,
-                            },
-                        )})
+                         let dpi_factor = self.with_window(xev.event, |window| {
+                            window.get_hidpi_factor()
+                        });
+                        if let Some(dpi_factor) = dpi_factor {
+                            let location = LogicalPosition::from_physical(
+                                (xev.event_x as f64, xev.event_y as f64),
+                                dpi_factor,
+                            );
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: WindowEvent::Touch(Touch {
+                                    device_id: mkdid(xev.deviceid),
+                                    phase,
+                                    location,
+                                    id: xev.detail as u64,
+                                }),
+                            })
+                        }
                     }
 
                     ffi::XI_RawButtonPress | ffi::XI_RawButtonRelease => {
@@ -986,7 +1088,44 @@ impl EventsLoop {
             _ => {
                 if event_type == self.randr_event_offset {
                     // In the future, it would be quite easy to emit monitor hotplug events.
-                    monitor::invalidate_cached_monitor_list();
+                    let prev_list = monitor::invalidate_cached_monitor_list();
+                    if let Some(prev_list) = prev_list {
+                        let new_list = self.xconn.get_available_monitors();
+                        for new_monitor in new_list {
+                            prev_list
+                                .iter()
+                                .find(|prev_monitor| prev_monitor.name == new_monitor.name)
+                                .map(|prev_monitor| {
+                                    if new_monitor.hidpi_factor != prev_monitor.hidpi_factor {
+                                        for (window_id, window) in self.windows.borrow().iter() {
+                                            if let Some(window) = window.upgrade() {
+                                                // Check if the window is on this monitor
+                                                let monitor = window.get_current_monitor();
+                                                if monitor.name == new_monitor.name {
+                                                    callback(Event::WindowEvent {
+                                                        window_id: mkwid(window_id.0),
+                                                        event: WindowEvent::HiDpiFactorChanged(
+                                                            new_monitor.hidpi_factor
+                                                        ),
+                                                    });
+                                                    let (width, height) = match window.get_inner_size_physical() {
+                                                        Some(result) => result,
+                                                        None => continue,
+                                                    };
+                                                    let (_, _, flusher) = window.adjust_for_dpi(
+                                                        prev_monitor.hidpi_factor,
+                                                        new_monitor.hidpi_factor,
+                                                        width as f64,
+                                                        height as f64,
+                                                    );
+                                                    flusher.queue();
+                                                }
+                                            }
+                                        }
+                                    }
+                                });
+                        }
+                    }
                 }
             },
         }
@@ -1110,16 +1249,13 @@ pub struct WindowId(ffi::Window);
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct DeviceId(c_int);
 
-pub struct Window {
-    pub window: Arc<UnownedWindow>,
-    ime_sender: Mutex<ImeSender>,
-}
+pub struct Window(Arc<UnownedWindow>);
 
 impl Deref for Window {
     type Target = UnownedWindow;
     #[inline]
     fn deref(&self) -> &UnownedWindow {
-        &*self.window
+        &*self.0
     }
 }
 
@@ -1130,35 +1266,19 @@ impl Window {
         pl_attribs: PlatformSpecificWindowBuilderAttributes
     ) -> Result<Self, CreationError> {
         let window = Arc::new(UnownedWindow::new(&event_loop, attribs, pl_attribs)?);
-
         event_loop.windows
             .borrow_mut()
             .insert(window.id(), Arc::downgrade(&window));
-
-        event_loop.ime
-            .borrow_mut()
-            .create_context(window.id().0)
-            .expect("Failed to create input context");
-
-        Ok(Window {
-            window,
-            ime_sender: Mutex::new(event_loop.ime_sender.clone()),
-        })
-    }
-
-    #[inline]
-    pub fn send_xim_spot(&self, x: i16, y: i16) {
-        let _ = self.ime_sender
-            .lock()
-            .send((self.window.id().0, x, y));
+        Ok(Window(window))
     }
 }
 
 impl Drop for Window {
     fn drop(&mut self) {
-        let xconn = &self.window.xconn;
+        let window = self.deref();
+        let xconn = &window.xconn;
         unsafe {
-            (xconn.xlib.XDestroyWindow)(xconn.display, self.window.id().0);
+            (xconn.xlib.XDestroyWindow)(xconn.display, window.id().0);
             // If the window was somehow already destroyed, we'll get a `BadWindow` error, which we don't care about.
             let _ = xconn.check_errors();
         }

src/platform/linux/x11/monitor.rs

@@ -1,8 +1,9 @@
 use std::os::raw::*;
-use std::sync::Arc;
 
 use parking_lot::Mutex;
 
+use {PhysicalPosition, PhysicalSize};
+use super::{util, XConnection, XError};
 use super::ffi::{
     RRCrtcChangeNotifyMask,
     RROutputPropertyNotifyMask,
@@ -11,7 +12,6 @@ use super::ffi::{
     Window,
     XRRScreenResources,
 };
-use super::{util, XConnection, XError};
 
 // Used to test XRandR < 1.5 code path. This should always be committed as false.
 const FORCE_RANDR_COMPAT: bool = false;
@@ -45,7 +45,7 @@ pub struct MonitorId {
     /// The actual id
     id: u32,
     /// The name of the monitor
-    name: String,
+    pub(crate) name: String,
     /// The size of the monitor
     dimensions: (u32, u32),
     /// The position of the monitor in the X screen
@@ -53,14 +53,14 @@ pub struct MonitorId {
     /// If the monitor is the primary one
     primary: bool,
     /// The DPI scale factor
-    pub(crate) hidpi_factor: f32,
+    pub(crate) hidpi_factor: f64,
     /// Used to determine which windows are on this monitor
     pub(crate) rect: util::Rect,
 }
 
 impl MonitorId {
     fn from_repr(
-        xconn: &Arc<XConnection>,
+        xconn: &XConnection,
         resources: *mut XRRScreenResources,
         id: u32,
         repr: util::MonitorRepr,
@@ -89,182 +89,181 @@ impl MonitorId {
         self.id as u32
     }
 
-    pub fn get_dimensions(&self) -> (u32, u32) {
-        self.dimensions
+    pub fn get_dimensions(&self) -> PhysicalSize {
+        self.dimensions.into()
     }
 
-    pub fn get_position(&self) -> (i32, i32) {
-        self.position
+    pub fn get_position(&self) -> PhysicalPosition {
+        self.position.into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         self.hidpi_factor
     }
 }
 
-pub fn get_monitor_for_window(
-    xconn: &Arc<XConnection>,
-    window_rect: Option<util::Rect>,
-) -> MonitorId {
-    let monitors = get_available_monitors(xconn);
-    let default = monitors
-        .get(0)
-        .expect("[winit] Failed to find any monitors using XRandR.");
+impl XConnection {
+    pub fn get_monitor_for_window(&self, window_rect: Option<util::Rect>) -> MonitorId {
+        let monitors = self.get_available_monitors();
+        let default = monitors
+            .get(0)
+            .expect("[winit] Failed to find any monitors using XRandR.");
 
-    let window_rect = match window_rect {
-        Some(rect) => rect,
-        None => return default.to_owned(),
-    };
+        let window_rect = match window_rect {
+            Some(rect) => rect,
+            None => return default.to_owned(),
+        };
 
-    let mut largest_overlap = 0;
-    let mut matched_monitor = default;
-    for monitor in &monitors {
-        let overlapping_area = window_rect.get_overlapping_area(&monitor.rect);
-        if overlapping_area > largest_overlap {
-            largest_overlap = overlapping_area;
-            matched_monitor = &monitor;
+        let mut largest_overlap = 0;
+        let mut matched_monitor = default;
+        for monitor in &monitors {
+            let overlapping_area = window_rect.get_overlapping_area(&monitor.rect);
+            if overlapping_area > largest_overlap {
+                largest_overlap = overlapping_area;
+                matched_monitor = &monitor;
+            }
         }
+
+        matched_monitor.to_owned()
     }
 
-    matched_monitor.to_owned()
-}
-
-fn query_monitor_list(xconn: &Arc<XConnection>) -> Vec<MonitorId> {
-    unsafe {
-        let root = (xconn.xlib.XDefaultRootWindow)(xconn.display);
-        // WARNING: this function is supposedly very slow, on the order of hundreds of ms.
-        // Upon failure, `resources` will be null.
-        let resources = (xconn.xrandr.XRRGetScreenResources)(xconn.display, root);
-        if resources.is_null() {
-            panic!("[winit] `XRRGetScreenResources` returned NULL. That should only happen if the root window doesn't exist.");
-        }
-
-        let mut available;
-        let mut has_primary = false;
-
-        if xconn.xrandr_1_5.is_some() && version_is_at_least(1, 5) && !FORCE_RANDR_COMPAT {
-            // We're in XRandR >= 1.5, enumerate monitors. This supports things like MST and
-            // videowalls.
-            let xrandr_1_5 = xconn.xrandr_1_5.as_ref().unwrap();
-            let mut monitor_count = 0;
-            let monitors = (xrandr_1_5.XRRGetMonitors)(xconn.display, root, 1, &mut monitor_count);
-            assert!(monitor_count >= 0);
-            available = Vec::with_capacity(monitor_count as usize);
-            for monitor_index in 0..monitor_count {
-                let monitor = monitors.offset(monitor_index as isize);
-                let is_primary = (*monitor).primary != 0;
-                has_primary |= is_primary;
-                available.push(MonitorId::from_repr(
-                    xconn,
-                    resources,
-                    monitor_index as u32,
-                    monitor.into(),
-                    is_primary,
-                ));
+    fn query_monitor_list(&self) -> Vec<MonitorId> {
+        unsafe {
+            let root = (self.xlib.XDefaultRootWindow)(self.display);
+            // WARNING: this function is supposedly very slow, on the order of hundreds of ms.
+            // Upon failure, `resources` will be null.
+            let resources = (self.xrandr.XRRGetScreenResources)(self.display, root);
+            if resources.is_null() {
+                panic!("[winit] `XRRGetScreenResources` returned NULL. That should only happen if the root window doesn't exist.");
             }
-            (xrandr_1_5.XRRFreeMonitors)(monitors);
-        } else {
-            // We're in XRandR < 1.5, enumerate CRTCs. Everything will work except MST and
-            // videowall setups will also show monitors that aren't in the logical groups the user
-            // cares about.
-            let primary = (xconn.xrandr.XRRGetOutputPrimary)(xconn.display, root);
-            available = Vec::with_capacity((*resources).ncrtc as usize);
-            for crtc_index in 0..(*resources).ncrtc {
-                let crtc_id = *((*resources).crtcs.offset(crtc_index as isize));
-                let crtc = (xconn.xrandr.XRRGetCrtcInfo)(xconn.display, resources, crtc_id);
-                let is_active = (*crtc).width > 0 && (*crtc).height > 0 && (*crtc).noutput > 0;
-                if is_active {
-                    let crtc = util::MonitorRepr::from(crtc);
-                    let is_primary = crtc.get_output() == primary;
+
+            let mut available;
+            let mut has_primary = false;
+
+            if self.xrandr_1_5.is_some() && version_is_at_least(1, 5) && !FORCE_RANDR_COMPAT {
+                // We're in XRandR >= 1.5, enumerate monitors. This supports things like MST and
+                // videowalls.
+                let xrandr_1_5 = self.xrandr_1_5.as_ref().unwrap();
+                let mut monitor_count = 0;
+                let monitors = (xrandr_1_5.XRRGetMonitors)(self.display, root, 1, &mut monitor_count);
+                assert!(monitor_count >= 0);
+                available = Vec::with_capacity(monitor_count as usize);
+                for monitor_index in 0..monitor_count {
+                    let monitor = monitors.offset(monitor_index as isize);
+                    let is_primary = (*monitor).primary != 0;
                     has_primary |= is_primary;
                     available.push(MonitorId::from_repr(
-                        xconn,
+                        self,
                         resources,
-                        crtc_id as u32,
-                        crtc,
+                        monitor_index as u32,
+                        monitor.into(),
                         is_primary,
                     ));
                 }
-                (xconn.xrandr.XRRFreeCrtcInfo)(crtc);
+                (xrandr_1_5.XRRFreeMonitors)(monitors);
+            } else {
+                // We're in XRandR < 1.5, enumerate CRTCs. Everything will work except MST and
+                // videowall setups will also show monitors that aren't in the logical groups the user
+                // cares about.
+                let primary = (self.xrandr.XRRGetOutputPrimary)(self.display, root);
+                available = Vec::with_capacity((*resources).ncrtc as usize);
+                for crtc_index in 0..(*resources).ncrtc {
+                    let crtc_id = *((*resources).crtcs.offset(crtc_index as isize));
+                    let crtc = (self.xrandr.XRRGetCrtcInfo)(self.display, resources, crtc_id);
+                    let is_active = (*crtc).width > 0 && (*crtc).height > 0 && (*crtc).noutput > 0;
+                    if is_active {
+                        let crtc = util::MonitorRepr::from(crtc);
+                        let is_primary = crtc.get_output() == primary;
+                        has_primary |= is_primary;
+                        available.push(MonitorId::from_repr(
+                            self,
+                            resources,
+                            crtc_id as u32,
+                            crtc,
+                            is_primary,
+                        ));
+                    }
+                    (self.xrandr.XRRFreeCrtcInfo)(crtc);
+                }
             }
-        }
 
-        // If no monitors were detected as being primary, we just pick one ourselves!
-        if !has_primary {
-            if let Some(ref mut fallback) = available.first_mut() {
-                // Setting this here will come in handy if we ever add an `is_primary` method.
-                fallback.primary = true;
+            // If no monitors were detected as being primary, we just pick one ourselves!
+            if !has_primary {
+                if let Some(ref mut fallback) = available.first_mut() {
+                    // Setting this here will come in handy if we ever add an `is_primary` method.
+                    fallback.primary = true;
+                }
             }
-        }
 
-        (xconn.xrandr.XRRFreeScreenResources)(resources);
-        available
-    }
-}
-
-pub fn get_available_monitors(xconn: &Arc<XConnection>) -> Vec<MonitorId> {
-    let mut monitors_lock = MONITORS.lock();
-    (*monitors_lock)
-        .as_ref()
-        .cloned()
-        .or_else(|| {
-            let monitors = Some(query_monitor_list(xconn));
-            if !DISABLE_MONITOR_LIST_CACHING {
-                (*monitors_lock) = monitors.clone();
-            }
-            monitors
-        })
-        .unwrap()
-}
-
-#[inline]
-pub fn get_primary_monitor(xconn: &Arc<XConnection>) -> MonitorId {
-    get_available_monitors(xconn)
-        .into_iter()
-        .find(|monitor| monitor.primary)
-        .expect("[winit] Failed to find any monitors using XRandR.")
-}
-
-pub fn select_input(xconn: &Arc<XConnection>, root: Window) -> Result<c_int, XError> {
-    {
-        let mut version_lock = XRANDR_VERSION.lock();
-        if version_lock.is_none() {
-            let mut major = 0;
-            let mut minor = 0;
-            let has_extension = unsafe {
-                (xconn.xrandr.XRRQueryVersion)(
-                    xconn.display,
-                    &mut major,
-                    &mut minor,
-                )
-            };
-            if has_extension != True {
-                panic!("[winit] XRandR extension not available.");
-            }
-            *version_lock = Some((major, minor));
+            (self.xrandr.XRRFreeScreenResources)(resources);
+            available
         }
     }
 
-    let mut event_offset = 0;
-    let mut error_offset = 0;
-    let status = unsafe {
-        (xconn.xrandr.XRRQueryExtension)(
-            xconn.display,
-            &mut event_offset,
-            &mut error_offset,
-        )
-    };
-
-    if status != True {
-        xconn.check_errors()?;
-        unreachable!("[winit] `XRRQueryExtension` failed but no error was received.");
+    pub fn get_available_monitors(&self) -> Vec<MonitorId> {
+        let mut monitors_lock = MONITORS.lock();
+        (*monitors_lock)
+            .as_ref()
+            .cloned()
+            .or_else(|| {
+                let monitors = Some(self.query_monitor_list());
+                if !DISABLE_MONITOR_LIST_CACHING {
+                    (*monitors_lock) = monitors.clone();
+                }
+                monitors
+            })
+            .unwrap()
     }
 
-    let mask = RRCrtcChangeNotifyMask
-        | RROutputPropertyNotifyMask
-        | RRScreenChangeNotifyMask;
-    unsafe { (xconn.xrandr.XRRSelectInput)(xconn.display, root, mask) };
+    #[inline]
+    pub fn get_primary_monitor(&self) -> MonitorId {
+        self.get_available_monitors()
+            .into_iter()
+            .find(|monitor| monitor.primary)
+            .expect("[winit] Failed to find any monitors using XRandR.")
+    }
 
-    Ok(event_offset)
+    pub fn select_xrandr_input(&self, root: Window) -> Result<c_int, XError> {
+        {
+            let mut version_lock = XRANDR_VERSION.lock();
+            if version_lock.is_none() {
+                let mut major = 0;
+                let mut minor = 0;
+                let has_extension = unsafe {
+                    (self.xrandr.XRRQueryVersion)(
+                        self.display,
+                        &mut major,
+                        &mut minor,
+                    )
+                };
+                if has_extension != True {
+                    panic!("[winit] XRandR extension not available.");
+                }
+                *version_lock = Some((major, minor));
+            }
+        }
+
+        let mut event_offset = 0;
+        let mut error_offset = 0;
+        let status = unsafe {
+            (self.xrandr.XRRQueryExtension)(
+                self.display,
+                &mut event_offset,
+                &mut error_offset,
+            )
+        };
+
+        if status != True {
+            self.check_errors()?;
+            unreachable!("[winit] `XRRQueryExtension` failed but no error was received.");
+        }
+
+        let mask = RRCrtcChangeNotifyMask
+            | RROutputPropertyNotifyMask
+            | RRScreenChangeNotifyMask;
+        unsafe { (self.xrandr.XRRSelectInput)(self.display, root, mask) };
+
+        Ok(event_offset)
+    }
 }

src/platform/linux/x11/util/geometry.rs

@@ -1,6 +1,7 @@
 use std::cmp;
 
 use super::*;
+use {LogicalPosition, LogicalSize};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Rect {
@@ -78,6 +79,24 @@ impl FrameExtents {
     pub fn from_border(border: c_ulong) -> Self {
         Self::new(border, border, border, border)
     }
+
+    pub fn as_logical(&self, factor: f64) -> LogicalFrameExtents {
+        let logicalize = |value: c_ulong| value as f64 / factor;
+        LogicalFrameExtents {
+            left: logicalize(self.left),
+            right: logicalize(self.right),
+            top: logicalize(self.top),
+            bottom: logicalize(self.bottom),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct LogicalFrameExtents {
+    pub left: f64,
+    pub right: f64,
+    pub top: f64,
+    pub bottom: f64,
 }
 
 #[derive(Debug, Clone, PartialEq)]
@@ -103,6 +122,16 @@ impl FrameExtentsHeuristic {
         }
     }
 
+    pub fn inner_pos_to_outer_logical(&self, mut logical: LogicalPosition, factor: f64) -> LogicalPosition {
+        use self::FrameExtentsHeuristicPath::*;
+        if self.heuristic_path != UnsupportedBordered {
+            let frame_extents = self.frame_extents.as_logical(factor);
+            logical.x -= frame_extents.left;
+            logical.y -= frame_extents.top;
+        }
+        logical
+    }
+
     pub fn inner_size_to_outer(&self, width: u32, height: u32) -> (u32, u32) {
         (
             width.saturating_add(
@@ -113,6 +142,13 @@ impl FrameExtentsHeuristic {
             ),
         )
     }
+
+    pub fn inner_size_to_outer_logical(&self, mut logical: LogicalSize, factor: f64) -> LogicalSize {
+        let frame_extents = self.frame_extents.as_logical(factor);
+        logical.width += frame_extents.left + frame_extents.right;
+        logical.height += frame_extents.top + frame_extents.bottom;
+        logical
+    }
 }
 
 impl XConnection {

src/platform/linux/x11/util/hint.rs

@@ -68,6 +68,99 @@ impl WindowType {
     }
 }
 
+pub struct NormalHints<'a> {
+    size_hints: XSmartPointer<'a, ffi::XSizeHints>,
+}
+
+impl<'a> NormalHints<'a> {
+    pub fn new(xconn: &'a XConnection) -> Self {
+        NormalHints { size_hints: xconn.alloc_size_hints() }
+    }
+
+    pub fn has_flag(&self, flag: c_long) -> bool {
+        has_flag(self.size_hints.flags, flag)
+    }
+
+    fn getter(&self, flag: c_long, field1: &c_int, field2: &c_int) -> Option<(u32, u32)> {
+        if self.has_flag(flag) {
+            Some((*field1 as _, *field2 as _))
+        } else {
+            None
+        }
+    }
+
+    pub fn get_size(&self) -> Option<(u32, u32)> {
+        self.getter(ffi::PSize, &self.size_hints.width, &self.size_hints.height)
+    }
+
+    // WARNING: This hint is obsolete
+    pub fn set_size(&mut self, size: Option<(u32, u32)>) {
+        if let Some((width, height)) = size {
+            self.size_hints.flags |= ffi::PSize;
+            self.size_hints.width = width as c_int;
+            self.size_hints.height = height as c_int;
+        } else {
+            self.size_hints.flags &= !ffi::PSize;
+        }
+    }
+
+    pub fn get_max_size(&self) -> Option<(u32, u32)> {
+        self.getter(ffi::PMaxSize, &self.size_hints.max_width, &self.size_hints.max_height)
+    }
+
+    pub fn set_max_size(&mut self, max_size: Option<(u32, u32)>) {
+        if let Some((max_width, max_height)) = max_size {
+            self.size_hints.flags |= ffi::PMaxSize;
+            self.size_hints.max_width = max_width as c_int;
+            self.size_hints.max_height = max_height as c_int;
+        } else {
+            self.size_hints.flags &= !ffi::PMaxSize;
+        }
+    }
+
+    pub fn get_min_size(&self) -> Option<(u32, u32)> {
+        self.getter(ffi::PMinSize, &self.size_hints.min_width, &self.size_hints.min_height)
+    }
+
+    pub fn set_min_size(&mut self, min_size: Option<(u32, u32)>) {
+        if let Some((min_width, min_height)) = min_size {
+            self.size_hints.flags |= ffi::PMinSize;
+            self.size_hints.min_width = min_width as c_int;
+            self.size_hints.min_height = min_height as c_int;
+        } else {
+            self.size_hints.flags &= !ffi::PMinSize;
+        }
+    }
+
+    pub fn get_resize_increments(&self) -> Option<(u32, u32)> {
+        self.getter(ffi::PResizeInc, &self.size_hints.width_inc, &self.size_hints.height_inc)
+    }
+
+    pub fn set_resize_increments(&mut self, resize_increments: Option<(u32, u32)>) {
+        if let Some((width_inc, height_inc)) = resize_increments {
+            self.size_hints.flags |= ffi::PResizeInc;
+            self.size_hints.width_inc = width_inc as c_int;
+            self.size_hints.height_inc = height_inc as c_int;
+        } else {
+            self.size_hints.flags &= !ffi::PResizeInc;
+        }
+    }
+
+    pub fn get_base_size(&self) -> Option<(u32, u32)> {
+        self.getter(ffi::PBaseSize, &self.size_hints.base_width, &self.size_hints.base_height)
+    }
+
+    pub fn set_base_size(&mut self, base_size: Option<(u32, u32)>) {
+        if let Some((base_width, base_height)) = base_size {
+            self.size_hints.flags |= ffi::PBaseSize;
+            self.size_hints.base_width = base_width as c_int;
+            self.size_hints.base_height = base_height as c_int;
+        } else {
+            self.size_hints.flags &= !ffi::PBaseSize;
+        }
+    }
+}
+
 impl XConnection {
     pub fn get_wm_hints(&self, window: ffi::Window) -> Result<XSmartPointer<ffi::XWMHints>, XError> {
         let wm_hints = unsafe { (self.xlib.XGetWMHints)(self.display, window) };
@@ -90,4 +183,29 @@ impl XConnection {
         }
         Flusher::new(self)
     }
+
+    pub fn get_normal_hints(&self, window: ffi::Window) -> Result<NormalHints, XError> {
+        let size_hints = self.alloc_size_hints();
+        let mut supplied_by_user: c_long = unsafe { mem::uninitialized() };
+        unsafe {
+            (self.xlib.XGetWMNormalHints)(
+                self.display,
+                window,
+                size_hints.ptr,
+                &mut supplied_by_user,
+            );
+        }
+        self.check_errors().map(|_| NormalHints { size_hints })
+    }
+
+    pub fn set_normal_hints(&self, window: ffi::Window, normal_hints: NormalHints) -> Flusher {
+        unsafe {
+            (self.xlib.XSetWMNormalHints)(
+                self.display,
+                window,
+                normal_hints.size_hints.ptr,
+            );
+        }
+        Flusher::new(self)
+    }
 }

src/platform/linux/x11/util/mod.rs

@@ -27,10 +27,16 @@ pub use self::wm::*;
 
 use std::mem;
 use std::ptr;
+use std::ops::BitAnd;
 use std::os::raw::*;
 
 use super::{ffi, XConnection, XError};
 
+pub fn reinterpret<'a, A, B>(a: &'a A) -> &'a B {
+    let b_ptr = a as *const _ as *const B;
+    unsafe { &*b_ptr }
+}
+
 pub fn maybe_change<T: PartialEq>(field: &mut Option<T>, value: T) -> bool {
     let wrapped = Some(value);
     if *field != wrapped {
@@ -41,6 +47,13 @@ pub fn maybe_change<T: PartialEq>(field: &mut Option<T>, value: T) -> bool {
     }
 }
 
+pub fn has_flag<T>(bitset: T, flag: T) -> bool
+where T:
+    Copy + PartialEq + BitAnd<T, Output = T>
+{
+    bitset & flag == flag
+}
+
 #[must_use = "This request was made asynchronously, and is still in the output buffer. You must explicitly choose to either `.flush()` (empty the output buffer, sending the request now) or `.queue()` (wait to send the request, allowing you to continue to add more requests without additional round-trips). For more information, see the documentation for `util::flush_requests`."]
 pub struct Flusher<'a> {
     xconn: &'a XConnection,

src/platform/linux/x11/util/randr.rs

@@ -1,21 +1,48 @@
 use std::{env, slice};
 use std::str::FromStr;
 
+use validate_hidpi_factor;
 use super::*;
-use super::ffi::{
-    RROutput,
-    XRRCrtcInfo,
-    XRRMonitorInfo,
-    XRRScreenResources,
-};
+
+pub fn calc_dpi_factor(
+    (width_px, height_px): (u32, u32),
+    (width_mm, height_mm): (u64, u64),
+) -> f64 {
+    // Override DPI if `WINIT_HIDPI_FACTOR` variable is set
+    let dpi_override = env::var("WINIT_HIDPI_FACTOR")
+        .ok()
+        .and_then(|var| f64::from_str(&var).ok());
+    if let Some(dpi_override) = dpi_override {
+        if !validate_hidpi_factor(dpi_override) {
+            panic!(
+                "`WINIT_HIDPI_FACTOR` invalid; DPI factors must be normal floats greater than 0. Got `{}`",
+                dpi_override,
+            );
+        }
+        return dpi_override;
+    }
+
+    // See http://xpra.org/trac/ticket/728 for more information.
+    if width_mm == 0 || width_mm == 0 {
+        return 1.0;
+    }
+
+    let ppmm = (
+        (width_px as f64 * height_px as f64) / (width_mm as f64 * height_mm as f64)
+    ).sqrt();
+    // Quantize 1/12 step size
+    let dpi_factor = ((ppmm * (12.0 * 25.4 / 96.0)).round() / 12.0).max(1.0);
+    assert!(validate_hidpi_factor(dpi_factor));
+    dpi_factor
+}
 
 pub enum MonitorRepr {
-    Monitor(*mut XRRMonitorInfo),
-    Crtc(*mut XRRCrtcInfo),
+    Monitor(*mut ffi::XRRMonitorInfo),
+    Crtc(*mut ffi::XRRCrtcInfo),
 }
 
 impl MonitorRepr {
-    pub unsafe fn get_output(&self) -> RROutput {
+    pub unsafe fn get_output(&self) -> ffi::RROutput {
         match *self {
             // Same member names, but different locations within the struct...
             MonitorRepr::Monitor(monitor) => *((*monitor).outputs.offset(0)),
@@ -38,47 +65,20 @@ impl MonitorRepr {
     }
 }
 
-impl From<*mut XRRMonitorInfo> for MonitorRepr {
-    fn from(monitor: *mut XRRMonitorInfo) -> Self {
+impl From<*mut ffi::XRRMonitorInfo> for MonitorRepr {
+    fn from(monitor: *mut ffi::XRRMonitorInfo) -> Self {
         MonitorRepr::Monitor(monitor)
     }
 }
 
-impl From<*mut XRRCrtcInfo> for MonitorRepr {
-    fn from(crtc: *mut XRRCrtcInfo) -> Self {
+impl From<*mut ffi::XRRCrtcInfo> for MonitorRepr {
+    fn from(crtc: *mut ffi::XRRCrtcInfo) -> Self {
         MonitorRepr::Crtc(crtc)
     }
 }
 
-pub fn calc_dpi_factor(
-    (width_px, height_px): (u32, u32),
-    (width_mm, height_mm): (u64, u64),
-) -> f64 {
-    // Override DPI if `WINIT_HIDPI_FACTOR` variable is set
-    if let Ok(dpi_factor_str) = env::var("WINIT_HIDPI_FACTOR") {
-        if let Ok(dpi_factor) = f64::from_str(&dpi_factor_str) {
-            if dpi_factor <= 0. {
-                panic!("Expected `WINIT_HIDPI_FACTOR` to be bigger than 0, got '{}'", dpi_factor);
-            }
-
-            return dpi_factor;
-        }
-    }
-
-    // See http://xpra.org/trac/ticket/728 for more information
-    if width_mm == 0 || width_mm == 0 {
-        return 1.0;
-    }
-
-    let ppmm = (
-        (width_px as f64 * height_px as f64) / (width_mm as f64 * height_mm as f64)
-    ).sqrt();
-    // Quantize 1/12 step size
-    ((ppmm * (12.0 * 25.4 / 96.0)).round() / 12.0).max(1.0)
-}
-
 impl XConnection {
-    pub unsafe fn get_output_info(&self, resources: *mut XRRScreenResources, repr: &MonitorRepr) -> (String, f32) {
+    pub unsafe fn get_output_info(&self, resources: *mut ffi::XRRScreenResources, repr: &MonitorRepr) -> (String, f64) {
         let output_info = (self.xrandr.XRRGetOutputInfo)(
             self.display,
             resources,
@@ -92,7 +92,7 @@ impl XConnection {
         let hidpi_factor = calc_dpi_factor(
             repr.get_dimensions(),
             ((*output_info).mm_width as u64, (*output_info).mm_height as u64),
-        ) as f32;
+        );
         (self.xrandr.XRRFreeOutputInfo)(output_info);
         (name, hidpi_factor)
     }

src/platform/linux/x11/window.rs

@@ -7,15 +7,14 @@ use std::sync::Arc;
 use libc;
 use parking_lot::Mutex;
 
-use {CursorState, Icon, MouseCursor, WindowAttributes};
+use {CursorState, Icon, LogicalPosition, LogicalSize, MouseCursor, WindowAttributes};
 use CreationError::{self, OsError};
 use platform::MonitorId as PlatformMonitorId;
 use platform::PlatformSpecificWindowBuilderAttributes;
 use platform::x11::MonitorId as X11MonitorId;
-use platform::x11::monitor::get_monitor_for_window;
 use window::MonitorId as RootMonitorId;
 
-use super::{ffi, util, XConnection, XError, WindowId, EventsLoop};
+use super::{ffi, util, ImeSender, XConnection, XError, WindowId, EventsLoop};
 
 unsafe extern "C" fn visibility_predicate(
     _display: *mut ffi::Display,
@@ -29,7 +28,8 @@ unsafe extern "C" fn visibility_predicate(
 
 #[derive(Debug, Default)]
 pub struct SharedState {
-    pub multitouch: bool,
+    // Window creation assumes a DPI factor of 1.0, so we use this flag to handle that special case.
+    pub is_new_window: bool,
     pub cursor_pos: Option<(f64, f64)>,
     pub size: Option<(u32, u32)>,
     pub position: Option<(i32, i32)>,
@@ -37,9 +37,19 @@ pub struct SharedState {
     pub inner_position_rel_parent: Option<(i32, i32)>,
     pub last_monitor: Option<X11MonitorId>,
     pub dpi_adjusted: Option<(f64, f64)>,
+    // Used to restore position after exiting fullscreen.
+    pub restore_position: Option<(i32, i32)>,
     pub frame_extents: Option<util::FrameExtentsHeuristic>,
-    pub min_dimensions: Option<(u32, u32)>,
-    pub max_dimensions: Option<(u32, u32)>,
+    pub min_dimensions: Option<LogicalSize>,
+    pub max_dimensions: Option<LogicalSize>,
+}
+
+impl SharedState {
+    fn new() -> Mutex<Self> {
+        let mut shared_state = SharedState::default();
+        shared_state.is_new_window = true;
+        Mutex::new(shared_state)
+    }
 }
 
 unsafe impl Send for UnownedWindow {}
@@ -52,6 +62,7 @@ pub struct UnownedWindow {
     screen_id: i32, // never changes
     cursor: Mutex<MouseCursor>,
     cursor_state: Mutex<CursorState>,
+    ime_sender: Mutex<ImeSender>,
     pub multitouch: bool, // never changes
     pub shared_state: Mutex<SharedState>,
 }
@@ -65,15 +76,20 @@ impl UnownedWindow {
         let xconn = &event_loop.xconn;
         let root = event_loop.root;
 
+        let max_dimensions: Option<(u32, u32)> = window_attrs.max_dimensions.map(Into::into);
+        let min_dimensions: Option<(u32, u32)> = window_attrs.min_dimensions.map(Into::into);
+
         let dimensions = {
             // x11 only applies constraints when the window is actively resized
             // by the user, so we have to manually apply the initial constraints
-            let mut dimensions = window_attrs.dimensions.unwrap_or((800, 600));
-            if let Some(max) = window_attrs.max_dimensions {
+            let mut dimensions = window_attrs.dimensions
+                .map(Into::into)
+                .unwrap_or((800, 600));
+            if let Some(max) = max_dimensions {
                 dimensions.0 = cmp::min(dimensions.0, max.0);
                 dimensions.1 = cmp::min(dimensions.1, max.1);
             }
-            if let Some(min) = window_attrs.min_dimensions {
+            if let Some(min) = min_dimensions {
                 dimensions.0 = cmp::max(dimensions.0, min.0);
                 dimensions.1 = cmp::max(dimensions.1, min.1);
             }
@@ -145,8 +161,9 @@ impl UnownedWindow {
             screen_id,
             cursor: Default::default(),
             cursor_state: Default::default(),
+            ime_sender: Mutex::new(event_loop.ime_sender.clone()),
             multitouch: window_attrs.multitouch,
-            shared_state: Default::default(),
+            shared_state: SharedState::new(),
         };
 
         // Title must be set before mapping. Some tiling window managers (i.e. i3) use the window
@@ -218,46 +235,24 @@ impl UnownedWindow {
 
             // set size hints
             {
-                (*window.shared_state.lock()).min_dimensions = window_attrs.min_dimensions;
-                (*window.shared_state.lock()).max_dimensions = window_attrs.max_dimensions;
                 let mut min_dimensions = window_attrs.min_dimensions;
                 let mut max_dimensions = window_attrs.max_dimensions;
                 if !window_attrs.resizable && !util::wm_name_is_one_of(&["Xfwm4"]) {
-                    max_dimensions = Some(dimensions);
-                    min_dimensions = Some(dimensions);
+                    max_dimensions = Some(dimensions.into());
+                    min_dimensions = Some(dimensions.into());
+
+                    let mut shared_state_lock = window.shared_state.lock();
+                    shared_state_lock.min_dimensions = window_attrs.min_dimensions;
+                    shared_state_lock.max_dimensions = window_attrs.max_dimensions;
                 }
 
-                let mut size_hints = xconn.alloc_size_hints();
-                (*size_hints).flags = ffi::PSize;
-                (*size_hints).width = dimensions.0 as c_int;
-                (*size_hints).height = dimensions.1 as c_int;
-                if let Some((min_width, min_height)) = min_dimensions {
-                    (*size_hints).flags |= ffi::PMinSize;
-                    (*size_hints).min_width = min_width as c_int;
-                    (*size_hints).min_height = min_height as c_int;
-                }
-                if let Some((max_width, max_height)) = max_dimensions {
-                    (*size_hints).flags |= ffi::PMaxSize;
-                    (*size_hints).max_width = max_width as c_int;
-                    (*size_hints).max_height = max_height as c_int;
-                }
-                if let Some((width_inc, height_inc)) = pl_attribs.resize_increments {
-                    (*size_hints).flags |= ffi::PResizeInc;
-                    (*size_hints).width_inc = width_inc as c_int;
-                    (*size_hints).height_inc = height_inc as c_int;
-                }
-                if let Some((base_width, base_height)) = pl_attribs.base_size {
-                    (*size_hints).flags |= ffi::PBaseSize;
-                    (*size_hints).base_width = base_width as c_int;
-                    (*size_hints).base_height = base_height as c_int;
-                }
-                unsafe {
-                    (xconn.xlib.XSetWMNormalHints)(
-                        xconn.display,
-                        window.xwindow,
-                        size_hints.ptr,
-                    );
-                }//.queue();
+                let mut normal_hints = util::NormalHints::new(xconn);
+                normal_hints.set_size(Some(dimensions));
+                normal_hints.set_min_size(min_dimensions.map(Into::into));
+                normal_hints.set_max_size(max_dimensions.map(Into::into));
+                normal_hints.set_resize_increments(pl_attribs.resize_increments);
+                normal_hints.set_base_size(pl_attribs.base_size);
+                xconn.set_normal_hints(window.xwindow, normal_hints).queue();
             }
 
             // Set window icons
@@ -291,7 +286,7 @@ impl UnownedWindow {
                     &mut supported_ptr,
                 );
                 if supported_ptr == ffi::False {
-                    return Err(OsError(format!("XkbSetDetectableAutoRepeat failed")));
+                    return Err(OsError(format!("`XkbSetDetectableAutoRepeat` failed")));
                 }
             }
 
@@ -315,6 +310,15 @@ impl UnownedWindow {
             };
             xconn.select_xinput_events(window.xwindow, ffi::XIAllMasterDevices, mask).queue();
 
+            {
+                let result = event_loop.ime
+                    .borrow_mut()
+                    .create_context(window.xwindow);
+                if let Err(err) = result {
+                    return Err(OsError(format!("Failed to create input context: {:?}", err)));
+                }
+            }
+
             // These properties must be set after mapping
             if window_attrs.maximized {
                 window.set_maximized_inner(window_attrs.maximized).queue();
@@ -355,6 +359,16 @@ impl UnownedWindow {
             ))
     }
 
+    fn logicalize_coords(&self, (x, y): (i32, i32)) -> LogicalPosition {
+        let dpi = self.get_hidpi_factor();
+        LogicalPosition::from_physical((x, y), dpi)
+    }
+
+    fn logicalize_size(&self, (width, height): (u32, u32)) -> LogicalSize {
+        let dpi = self.get_hidpi_factor();
+        LogicalSize::from_physical((width, height), dpi)
+    }
+
     fn set_pid(&self) -> Option<util::Flusher> {
         let pid_atom = unsafe { self.xconn.get_atom_unchecked(b"_NET_WM_PID\0") };
         let client_machine_atom = unsafe { self.xconn.get_atom_unchecked(b"WM_CLIENT_MACHINE\0") };
@@ -400,6 +414,7 @@ impl UnownedWindow {
         )
     }
 
+    #[inline]
     pub fn set_urgent(&self, is_urgent: bool) {
         let mut wm_hints = self.xconn.get_wm_hints(self.xwindow).expect("`XGetWMHints` failed");
         if is_urgent {
@@ -439,17 +454,24 @@ impl UnownedWindow {
     fn set_fullscreen_inner(&self, monitor: Option<RootMonitorId>) -> util::Flusher {
         match monitor {
             None => {
-                self.set_fullscreen_hint(false)
+                let flusher = self.set_fullscreen_hint(false);
+                if let Some(position) = self.shared_state.lock().restore_position.take() {
+                    self.set_position_inner(position.0, position.1).queue();
+                }
+                flusher
             },
             Some(RootMonitorId { inner: PlatformMonitorId::X(monitor) }) => {
-                let screenpos = monitor.get_position();
-                self.set_position(screenpos.0 as i32, screenpos.1 as i32);
+                let window_position = self.get_position_physical();
+                self.shared_state.lock().restore_position = window_position;
+                let monitor_origin: (i32, i32) = monitor.get_position().into();
+                self.set_position_inner(monitor_origin.0, monitor_origin.1).queue();
                 self.set_fullscreen_hint(true)
             }
             _ => unreachable!(),
         }
     }
 
+    #[inline]
     pub fn set_fullscreen(&self, monitor: Option<RootMonitorId>) {
         self.set_fullscreen_inner(monitor)
             .flush()
@@ -459,15 +481,26 @@ impl UnownedWindow {
 
     fn get_rect(&self) -> Option<util::Rect> {
         // TODO: This might round-trip more times than needed.
-        if let (Some(position), Some(size)) = (self.get_position(), self.get_outer_size()) {
+        if let (Some(position), Some(size)) = (self.get_position_physical(), self.get_outer_size_physical()) {
             Some(util::Rect::new(position, size))
         } else {
             None
         }
     }
 
+    #[inline]
     pub fn get_current_monitor(&self) -> X11MonitorId {
-        get_monitor_for_window(&self.xconn, self.get_rect()).to_owned()
+        let monitor = self.shared_state
+            .lock()
+            .last_monitor
+            .as_ref()
+            .cloned();
+        monitor
+            .unwrap_or_else(|| {
+                let monitor = self.xconn.get_monitor_for_window(self.get_rect()).to_owned();
+                self.shared_state.lock().last_monitor = Some(monitor.clone());
+                monitor
+            })
     }
 
     fn set_maximized_inner(&self, maximized: bool) -> util::Flusher {
@@ -476,6 +509,7 @@ impl UnownedWindow {
         self.set_netwm(maximized.into(), (horz_atom as c_long, vert_atom as c_long, 0, 0))
     }
 
+    #[inline]
     pub fn set_maximized(&self, maximized: bool) {
         self.set_maximized_inner(maximized)
             .flush()
@@ -503,6 +537,7 @@ impl UnownedWindow {
         }
     }
 
+    #[inline]
     pub fn set_title(&self, title: &str) {
         self.set_title_inner(title)
             .flush()
@@ -526,6 +561,7 @@ impl UnownedWindow {
         )
     }
 
+    #[inline]
     pub fn set_decorations(&self, decorations: bool) {
         self.set_decorations_inner(decorations)
             .flush()
@@ -538,6 +574,7 @@ impl UnownedWindow {
         self.set_netwm(always_on_top.into(), (above_atom as c_long, 0, 0, 0))
     }
 
+    #[inline]
     pub fn set_always_on_top(&self, always_on_top: bool) {
         self.set_always_on_top_inner(always_on_top)
             .flush()
@@ -568,6 +605,7 @@ impl UnownedWindow {
         )
     }
 
+    #[inline]
     pub fn set_window_icon(&self, icon: Option<Icon>) {
         match icon {
             Some(icon) => self.set_icon_inner(icon),
@@ -575,6 +613,7 @@ impl UnownedWindow {
         }.flush().expect("Failed to set icons");
     }
 
+    #[inline]
     pub fn show(&self) {
         unsafe {
             (self.xconn.xlib.XMapRaised)(self.xconn.display, self.xwindow);
@@ -583,6 +622,7 @@ impl UnownedWindow {
         }
     }
 
+    #[inline]
     pub fn hide(&self) {
         unsafe {
             (self.xconn.xlib.XUnmapWindow)(self.xconn.display, self.xwindow);
@@ -596,31 +636,46 @@ impl UnownedWindow {
         (*self.shared_state.lock()).frame_extents = Some(extents);
     }
 
-    pub fn invalidate_cached_frame_extents(&self) {
+    pub(crate) fn invalidate_cached_frame_extents(&self) {
         (*self.shared_state.lock()).frame_extents.take();
     }
 
-    #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub(crate) fn get_position_physical(&self) -> Option<(i32, i32)> {
         let extents = (*self.shared_state.lock()).frame_extents.clone();
         if let Some(extents) = extents {
-            self.get_inner_position().map(|(x, y)|
-                extents.inner_pos_to_outer(x, y)
-            )
+            self.get_inner_position_physical()
+                .map(|(x, y)| extents.inner_pos_to_outer(x, y))
+        } else {
+            self.update_cached_frame_extents();
+            self.get_position_physical()
+        }
+    }
+
+    #[inline]
+    pub fn get_position(&self) -> Option<LogicalPosition> {
+        let extents = (*self.shared_state.lock()).frame_extents.clone();
+        if let Some(extents) = extents {
+            self.get_inner_position()
+                .map(|logical| extents.inner_pos_to_outer_logical(logical, self.get_hidpi_factor()))
         } else {
             self.update_cached_frame_extents();
             self.get_position()
         }
     }
 
-    #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
-        self.xconn.translate_coords(self.xwindow, self.root )
+    pub(crate) fn get_inner_position_physical(&self) -> Option<(i32, i32)> {
+        self.xconn.translate_coords(self.xwindow, self.root)
             .ok()
             .map(|coords| (coords.x_rel_root, coords.y_rel_root))
     }
 
-    pub fn set_position(&self, mut x: i32, mut y: i32) {
+    #[inline]
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
+        self.get_inner_position_physical()
+            .map(|coords| self.logicalize_coords(coords))
+    }
+
+    pub(crate) fn set_position_inner(&self, mut x: i32, mut y: i32) -> util::Flusher {
         // There are a few WMs that set client area position rather than window position, so
         // we'll translate for consistency.
         if util::wm_name_is_one_of(&["Enlightenment", "FVWM"]) {
@@ -630,7 +685,7 @@ impl UnownedWindow {
                 y += extents.frame_extents.top as i32;
             } else {
                 self.update_cached_frame_extents();
-                self.set_position(x, y)
+                return self.set_position_inner(x, y);
             }
         }
         unsafe {
@@ -640,32 +695,58 @@ impl UnownedWindow {
                 x as c_int,
                 y as c_int,
             );
-            self.xconn.flush_requests()
-        }.expect("Failed to call XMoveWindow");
+        }
+        util::Flusher::new(&self.xconn)
+    }
+
+    pub(crate) fn set_position_physical(&self, x: i32, y: i32) {
+        self.set_position_inner(x, y)
+            .flush()
+            .expect("Failed to call `XMoveWindow`");
     }
 
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    pub fn set_position(&self, logical_position: LogicalPosition) {
+        let (x, y) = logical_position.to_physical(self.get_hidpi_factor()).into();
+        self.set_position_physical(x, y);
+    }
+
+    pub(crate) fn get_inner_size_physical(&self) -> Option<(u32, u32)> {
         self.xconn.get_geometry(self.xwindow)
             .ok()
             .map(|geo| (geo.width, geo.height))
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
-        let extents = (*self.shared_state.lock()).frame_extents.clone();
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
+        self.get_inner_size_physical()
+            .map(|size| self.logicalize_size(size))
+    }
+
+    pub(crate) fn get_outer_size_physical(&self) -> Option<(u32, u32)> {
+        let extents = self.shared_state.lock().frame_extents.clone();
         if let Some(extents) = extents {
-            self.get_inner_size().map(|(w, h)|
-                extents.inner_size_to_outer(w, h)
-            )
+            self.get_inner_size_physical()
+                .map(|(w, h)| extents.inner_size_to_outer(w, h))
+        } else {
+            self.update_cached_frame_extents();
+            self.get_outer_size_physical()
+        }
+    }
+
+    #[inline]
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
+        let extents = self.shared_state.lock().frame_extents.clone();
+        if let Some(extents) = extents {
+            self.get_inner_size()
+                .map(|logical| extents.inner_size_to_outer_logical(logical, self.get_hidpi_factor()))
         } else {
             self.update_cached_frame_extents();
             self.get_outer_size()
         }
     }
 
-    #[inline]
-    pub fn set_inner_size(&self, width: u32, height: u32) {
+    pub(crate) fn set_inner_size_physical(&self, width: u32, height: u32) {
         unsafe {
             (self.xconn.xlib.XResizeWindow)(
                 self.xconn.display,
@@ -674,62 +755,86 @@ impl UnownedWindow {
                 height as c_uint,
             );
             self.xconn.flush_requests()
-        }.expect("Failed to call XResizeWindow");
+        }.expect("Failed to call `XResizeWindow`");
     }
 
-    unsafe fn update_normal_hints<F>(&self, callback: F) -> Result<(), XError>
-        where F: FnOnce(*mut ffi::XSizeHints) -> ()
+    #[inline]
+    pub fn set_inner_size(&self, logical_size: LogicalSize) {
+        let dpi_factor = self.get_hidpi_factor();
+        let (width, height) = logical_size.to_physical(dpi_factor).into();
+        self.set_inner_size_physical(width, height);
+    }
+
+    fn update_normal_hints<F>(&self, callback: F) -> Result<(), XError>
+        where F: FnOnce(&mut util::NormalHints) -> ()
     {
-        let size_hints = self.xconn.alloc_size_hints();
-        let mut flags: c_long = mem::uninitialized();
-        (self.xconn.xlib.XGetWMNormalHints)(
-            self.xconn.display,
-            self.xwindow,
-            size_hints.ptr,
-            &mut flags,
-        );
-        self.xconn.check_errors()?;
-
-        callback(size_hints.ptr);
-
-        (self.xconn.xlib.XSetWMNormalHints)(
-            self.xconn.display,
-            self.xwindow,
-            size_hints.ptr,
-        );
-        self.xconn.flush_requests()?;
-
-        Ok(())
+        let mut normal_hints = self.xconn.get_normal_hints(self.xwindow)?;
+        callback(&mut normal_hints);
+        self.xconn.set_normal_hints(self.xwindow, normal_hints).flush()
     }
 
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        (*self.shared_state.lock()).min_dimensions = dimensions;
-        unsafe {
-            self.update_normal_hints(|size_hints| {
-                if let Some((width, height)) = dimensions {
-                    (*size_hints).flags |= ffi::PMinSize;
-                    (*size_hints).min_width = width as c_int;
-                    (*size_hints).min_height = height as c_int;
-                } else {
-                    (*size_hints).flags &= !ffi::PMinSize;
-                }
-            })
-        }.expect("Failed to call XSetWMNormalHints");
+    pub(crate) fn set_min_dimensions_physical(&self, dimensions: Option<(u32, u32)>) {
+        self.update_normal_hints(|normal_hints| normal_hints.set_min_size(dimensions))
+            .expect("Failed to call `XSetWMNormalHints`");
     }
 
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        (*self.shared_state.lock()).max_dimensions = dimensions;
+    #[inline]
+    pub fn set_min_dimensions(&self, logical_dimensions: Option<LogicalSize>) {
+        self.shared_state.lock().min_dimensions = logical_dimensions;
+        let physical_dimensions = logical_dimensions.map(|logical_dimensions| {
+            logical_dimensions.to_physical(self.get_hidpi_factor()).into()
+        });
+        self.set_min_dimensions_physical(physical_dimensions);
+    }
+
+    pub(crate) fn set_max_dimensions_physical(&self, dimensions: Option<(u32, u32)>) {
+        self.update_normal_hints(|normal_hints| normal_hints.set_max_size(dimensions))
+            .expect("Failed to call `XSetWMNormalHints`");
+    }
+
+    #[inline]
+    pub fn set_max_dimensions(&self, logical_dimensions: Option<LogicalSize>) {
+        self.shared_state.lock().max_dimensions = logical_dimensions;
+        let physical_dimensions = logical_dimensions.map(|logical_dimensions| {
+            logical_dimensions.to_physical(self.get_hidpi_factor()).into()
+        });
+        self.set_max_dimensions_physical(physical_dimensions);
+    }
+
+    pub(crate) fn adjust_for_dpi(
+        &self,
+        old_dpi_factor: f64,
+        new_dpi_factor: f64,
+        width: f64,
+        height: f64,
+    ) -> (f64, f64, util::Flusher) {
+        let scale_factor = new_dpi_factor / old_dpi_factor;
+        let new_width = width * scale_factor;
+        let new_height = height * scale_factor;
+        self.update_normal_hints(|normal_hints| {
+            let dpi_adjuster = |(width, height): (u32, u32)| -> (u32, u32) {
+                let new_width = width as f64 * scale_factor;
+                let new_height = height as f64 * scale_factor;
+                (new_width.round() as u32, new_height.round() as u32)
+            };
+            let max_size = normal_hints.get_max_size().map(&dpi_adjuster);
+            let min_size = normal_hints.get_min_size().map(&dpi_adjuster);
+            let resize_increments = normal_hints.get_resize_increments().map(&dpi_adjuster);
+            let base_size = normal_hints.get_base_size().map(&dpi_adjuster);
+            normal_hints.set_max_size(max_size);
+            normal_hints.set_min_size(min_size);
+            normal_hints.set_resize_increments(resize_increments);
+            normal_hints.set_base_size(base_size);
+        }).expect("Failed to update normal hints");
         unsafe {
-            self.update_normal_hints(|size_hints| {
-                if let Some((width, height)) = dimensions {
-                    (*size_hints).flags |= ffi::PMaxSize;
-                    (*size_hints).max_width = width as c_int;
-                    (*size_hints).max_height = height as c_int;
-                } else {
-                    (*size_hints).flags &= !ffi::PMaxSize;
-                }
-            })
-        }.expect("Failed to call XSetWMNormalHints");
+            (self.xconn.xlib.XResizeWindow)(
+                self.xconn.display,
+                self.xwindow,
+                new_width.round() as c_uint,
+                new_height.round() as c_uint,
+            );
+        }
+        (new_width, new_height, util::Flusher::new(&self.xconn))
     }
 
     pub fn set_resizable(&self, resizable: bool) {
@@ -739,24 +844,26 @@ impl UnownedWindow {
             // the lesser of two evils and do nothing.
             return;
         }
-        if resizable {
-            let min_dimensions = (*self.shared_state.lock()).min_dimensions;
-            let max_dimensions = (*self.shared_state.lock()).max_dimensions;
-            self.set_min_dimensions(min_dimensions);
-            self.set_max_dimensions(max_dimensions);
+
+        let (logical_min, logical_max) = if resizable {
+            let shared_state_lock = self.shared_state.lock();
+            (shared_state_lock.min_dimensions, shared_state_lock.max_dimensions)
         } else {
-            unsafe {
-                self.update_normal_hints(|size_hints| {
-                    (*size_hints).flags |= ffi::PMinSize | ffi::PMaxSize;
-                    if let Some((width, height)) = self.get_inner_size() {
-                        (*size_hints).min_width = width as c_int;
-                        (*size_hints).min_height = height as c_int;
-                        (*size_hints).max_width = width as c_int;
-                        (*size_hints).max_height = height as c_int;
-                    }
-                })
-            }.expect("Failed to call XSetWMNormalHints");
-        }
+            let window_size = self.get_inner_size();
+            (window_size.clone(), window_size)
+        };
+
+        let dpi_factor = self.get_hidpi_factor();
+        let min_dimensions = logical_min
+            .map(|logical_size| logical_size.to_physical(dpi_factor))
+            .map(Into::into);
+        let max_dimensions = logical_max
+            .map(|logical_size| logical_size.to_physical(dpi_factor))
+            .map(Into::into);
+        self.update_normal_hints(|normal_hints| {
+            normal_hints.set_min_size(min_dimensions);
+            normal_hints.set_max_size(max_dimensions);
+        }).expect("Failed to call `XSetWMNormalHints`");
     }
 
     #[inline]
@@ -774,21 +881,12 @@ impl UnownedWindow {
         Arc::clone(&self.xconn)
     }
 
-    #[inline]
-    pub fn platform_display(&self) -> *mut libc::c_void {
-        self.xconn.display as _
-    }
-
     #[inline]
     pub fn get_xlib_window(&self) -> c_ulong {
         self.xwindow
     }
 
     #[inline]
-    pub fn platform_window(&self) -> *mut libc::c_void {
-        self.xwindow as _
-    }
-
     pub fn get_xcb_connection(&self) -> *mut c_void {
         unsafe {
             (self.xconn.xlib_xcb.XGetXCBConnection)(self.xconn.display) as *mut _
@@ -886,6 +984,7 @@ impl UnownedWindow {
         }
     }
 
+    #[inline]
     pub fn set_cursor(&self, cursor: MouseCursor) {
         *self.cursor.lock() = cursor;
         if *self.cursor_state.lock() != CursorState::Hide {
@@ -931,6 +1030,7 @@ impl UnownedWindow {
         Some(cursor)
     }
 
+    #[inline]
     pub fn set_cursor_state(&self, state: CursorState) -> Result<(), String> {
         use CursorState::*;
 
@@ -994,11 +1094,12 @@ impl UnownedWindow {
         }
     }
 
-    pub fn hidpi_factor(&self) -> f32 {
+    #[inline]
+    pub fn get_hidpi_factor(&self) -> f64 {
         self.get_current_monitor().hidpi_factor
     }
 
-    pub fn set_cursor_position(&self, x: i32, y: i32) -> Result<(), ()> {
+    pub(crate) fn set_cursor_position_physical(&self, x: i32, y: i32) -> Result<(), ()> {
         unsafe {
             (self.xconn.xlib.XWarpPointer)(
                 self.xconn.display,
@@ -1015,6 +1116,24 @@ impl UnownedWindow {
         }
     }
 
+    #[inline]
+    pub fn set_cursor_position(&self, logical_position: LogicalPosition) -> Result<(), ()> {
+        let (x, y) = logical_position.to_physical(self.get_hidpi_factor()).into();
+        self.set_cursor_position_physical(x, y)
+    }
+
+    pub(crate) fn set_ime_spot_physical(&self, x: i32, y: i32) {
+        let _ = self.ime_sender
+            .lock()
+            .send((self.xwindow, x as i16, y as i16));
+    }
+
+    #[inline]
+    pub fn set_ime_spot(&self, logical_spot: LogicalPosition) {
+        let (x, y) = logical_spot.to_physical(self.get_hidpi_factor()).into();
+        self.set_ime_spot_physical(x, y);
+    }
+
     #[inline]
     pub fn id(&self) -> WindowId { WindowId(self.xwindow) }
 }

src/platform/macos/events_loop.rs

@@ -377,14 +377,16 @@ impl EventsLoop {
                 } else {
                     window.view.convertPoint_fromView_(window_point, cocoa::base::nil)
                 };
+
                 let view_rect = NSView::frame(*window.view);
-                let scale_factor = window.hidpi_factor();
-
-                let x = (scale_factor * view_point.x as f32) as f64;
-                let y = (scale_factor * (view_rect.size.height - view_point.y) as f32) as f64;
-                let window_event = WindowEvent::CursorMoved { device_id: DEVICE_ID, position: (x, y), modifiers: event_mods(ns_event) };
+                let x = view_point.x as f64;
+                let y = (view_rect.size.height - view_point.y) as f64;
+                let window_event = WindowEvent::CursorMoved {
+                    device_id: DEVICE_ID,
+                    position: (x, y).into(),
+                    modifiers: event_mods(ns_event),
+                };
                 let event = Event::WindowEvent { window_id: ::WindowId(window.id()), event: window_event };
-
                 self.shared.pending_events.lock().unwrap().push_back(event);
                 Some(into_event(WindowEvent::CursorEntered { device_id: DEVICE_ID }))
             },
@@ -402,27 +404,25 @@ impl EventsLoop {
                     None => return None,
                 };
 
-                let scale_factor = window.hidpi_factor();
-
                 let mut events = std::collections::VecDeque::with_capacity(3);
 
-                let delta_x = (scale_factor * ns_event.deltaX() as f32) as f64;
+                let delta_x = ns_event.deltaX() as f64;
                 if delta_x != 0.0 {
                     let motion_event = DeviceEvent::Motion { axis: 0, value: delta_x };
-                    let event = Event::DeviceEvent{ device_id: DEVICE_ID, event: motion_event };
+                    let event = Event::DeviceEvent { device_id: DEVICE_ID, event: motion_event };
                     events.push_back(event);
                 }
 
-                let delta_y = (scale_factor * ns_event.deltaY() as f32) as f64;
+                let delta_y = ns_event.deltaY() as f64;
                 if delta_y != 0.0 {
                     let motion_event = DeviceEvent::Motion { axis: 1, value: delta_y };
-                    let event = Event::DeviceEvent{ device_id: DEVICE_ID, event: motion_event };
+                    let event = Event::DeviceEvent { device_id: DEVICE_ID, event: motion_event };
                     events.push_back(event);
                 }
 
                 if delta_x != 0.0 || delta_y != 0.0 {
                     let motion_event = DeviceEvent::MouseMotion { delta: (delta_x, delta_y) };
-                    let event = Event::DeviceEvent{ device_id: DEVICE_ID, event: motion_event };
+                    let event = Event::DeviceEvent { device_id: DEVICE_ID, event: motion_event };
                     events.push_back(event);
                 }
 
@@ -433,19 +433,22 @@ impl EventsLoop {
 
             appkit::NSScrollWheel => {
                 // If none of the windows received the scroll, return `None`.
-                let window = match maybe_window {
-                    Some(window) => window,
-                    None => return None,
-                };
+                if maybe_window.is_none() {
+                    return None;
+                }
 
                 use events::MouseScrollDelta::{LineDelta, PixelDelta};
-                let scale_factor = window.hidpi_factor();
                 let delta = if ns_event.hasPreciseScrollingDeltas() == cocoa::base::YES {
-                    PixelDelta(scale_factor * ns_event.scrollingDeltaX() as f32,
-                               scale_factor * ns_event.scrollingDeltaY() as f32)
+                    PixelDelta((
+                        ns_event.scrollingDeltaX() as f64,
+                        ns_event.scrollingDeltaY() as f64,
+                    ).into())
                 } else {
-                    LineDelta(scale_factor * ns_event.scrollingDeltaX() as f32,
-                              scale_factor * ns_event.scrollingDeltaY() as f32)
+                    // TODO: This is probably wrong
+                    LineDelta(
+                        ns_event.scrollingDeltaX() as f32,
+                        ns_event.scrollingDeltaY() as f32,
+                    )
                 };
                 let phase = match ns_event.phase() {
                     NSEventPhase::NSEventPhaseMayBegin | NSEventPhase::NSEventPhaseBegan => TouchPhase::Started,
@@ -456,11 +459,15 @@ impl EventsLoop {
                     device_id: DEVICE_ID,
                     event: DeviceEvent::MouseWheel {
                         delta: if ns_event.hasPreciseScrollingDeltas() == cocoa::base::YES {
-                            PixelDelta(ns_event.scrollingDeltaX() as f32,
-                                       ns_event.scrollingDeltaY() as f32)
+                            PixelDelta((
+                                ns_event.scrollingDeltaX() as f64,
+                                ns_event.scrollingDeltaY() as f64,
+                            ).into())
                         } else {
-                            LineDelta(ns_event.scrollingDeltaX() as f32,
-                                      ns_event.scrollingDeltaY() as f32)
+                            LineDelta(
+                                ns_event.scrollingDeltaX() as f32,
+                                ns_event.scrollingDeltaY() as f32,
+                            )
                         },
                     }
                 });

src/platform/macos/monitor.rs

@@ -1,9 +1,12 @@
+use std::collections::VecDeque;
+use std::fmt;
+
 use cocoa::appkit::NSScreen;
 use cocoa::base::{id, nil};
 use cocoa::foundation::{NSString, NSUInteger};
 use core_graphics::display::{CGDirectDisplayID, CGDisplay, CGDisplayBounds};
-use std::collections::VecDeque;
-use std::fmt;
+
+use {PhysicalPosition, PhysicalSize};
 use super::EventsLoop;
 use super::window::IdRef;
 
@@ -39,9 +42,9 @@ impl fmt::Debug for MonitorId {
         struct MonitorId {
             name: Option<String>,
             native_identifier: u32,
-            dimensions: (u32, u32),
-            position: (i32, i32),
-            hidpi_factor: f32,
+            dimensions: PhysicalSize,
+            position: PhysicalPosition,
+            hidpi_factor: f64,
         }
 
         let monitor_id_proxy = MonitorId {
@@ -68,30 +71,32 @@ impl MonitorId {
         self.0
     }
 
-    pub fn get_dimensions(&self) -> (u32, u32) {
+    pub fn get_dimensions(&self) -> PhysicalSize {
         let MonitorId(display_id) = *self;
         let display = CGDisplay::new(display_id);
-        let dimension = {
-            let height = display.pixels_high();
-            let width = display.pixels_wide();
-            (width as u32, height as u32)
-        };
-        dimension
+        let height = display.pixels_high();
+        let width = display.pixels_wide();
+        PhysicalSize::from_logical(
+            (width as f64, height as f64),
+            self.get_hidpi_factor(),
+        )
     }
 
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         let bounds = unsafe { CGDisplayBounds(self.get_native_identifier()) };
-        (bounds.origin.x as i32, bounds.origin.y as i32)
+        PhysicalPosition::from_logical(
+            (bounds.origin.x as f64, bounds.origin.y as f64),
+            self.get_hidpi_factor(),
+        )
     }
 
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         let screen = match self.get_nsscreen() {
             Some(screen) => screen,
             None => return 1.0, // default to 1.0 when we can't find the screen
         };
-
-        unsafe { NSScreen::backingScaleFactor(screen) as f32 }
+        unsafe { NSScreen::backingScaleFactor(screen) as f64 }
     }
 
     pub(crate) fn get_nsscreen(&self) -> Option<id> {

src/platform/macos/util.rs

@@ -14,8 +14,8 @@ pub const EMPTY_RANGE: ffi::NSRange = ffi::NSRange {
 // For consistency with other platforms, this will...
 // 1. translate the bottom-left window corner into the top-left window corner
 // 2. translate the coordinate from a bottom-left origin coordinate system to a top-left one
-pub fn bottom_left_to_top_left(rect: NSRect) -> i32 {
-    (CGDisplay::main().pixels_high() as f64 - (rect.origin.y + rect.size.height)) as _
+pub fn bottom_left_to_top_left(rect: NSRect) -> f64 {
+    CGDisplay::main().pixels_high() as f64 - (rect.origin.y + rect.size.height)
 }
 
 pub unsafe fn set_style_mask(window: id, view: id, mask: NSWindowStyleMask) {

src/platform/macos/view.rs

@@ -22,7 +22,7 @@ use platform::platform::window::{get_window_id, IdRef};
 struct ViewState {
     window: id,
     shared: Weak<Shared>,
-    ime_spot: Option<(i32, i32)>,
+    ime_spot: Option<(f64, f64)>,
     raw_characters: Option<String>,
     last_insert: Option<String>,
 }
@@ -43,7 +43,7 @@ pub fn new_view(window: id, shared: Weak<Shared>) -> IdRef {
     }
 }
 
-pub fn set_ime_spot(view: id, input_context: id, x: i32, y: i32) {
+pub fn set_ime_spot(view: id, input_context: id, x: f64, y: f64) {
     unsafe {
         let state_ptr: *mut c_void = *(*view).get_mut_ivar("winitState");
         let state = &mut *(state_ptr as *mut ViewState);
@@ -51,8 +51,8 @@ pub fn set_ime_spot(view: id, input_context: id, x: i32, y: i32) {
             state.window,
             NSWindow::frame(state.window),
         );
-        let base_x = content_rect.origin.x as i32;
-        let base_y = (content_rect.origin.y + content_rect.size.height) as i32;
+        let base_x = content_rect.origin.x as f64;
+        let base_y = (content_rect.origin.y + content_rect.size.height) as f64;
         state.ime_spot = Some((base_x + x, base_y - y));
         let _: () = msg_send![input_context, invalidateCharacterCoordinates];
     }
@@ -249,7 +249,7 @@ extern fn first_rect_for_character_range(
             );
             let x = content_rect.origin.x;
             let y = util::bottom_left_to_top_left(content_rect);
-            (x as i32, y as i32)
+            (x, y)
         });
 
         NSRect::new(
@@ -527,15 +527,14 @@ fn mouse_motion(this: &Object, event: id) {
             return;
         }
 
-        let scale_factor = NSWindow::backingScaleFactor(state.window) as f64;
-        let x = scale_factor * view_point.x as f64;
-        let y = scale_factor * (view_rect.size.height as f64 - view_point.y as f64);
+        let x = view_point.x as f64;
+        let y = view_rect.size.height as f64 - view_point.y as f64;
 
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.window)),
             event: WindowEvent::CursorMoved {
                 device_id: DEVICE_ID,
-                position: (x, y),
+                position: (x, y).into(),
                 modifiers: event_mods(event),
             },
         };

src/platform/macos/window.rs

@@ -1,40 +1,52 @@
-use {CreationError, Event, WindowEvent, WindowId, MouseCursor, CursorState};
-use CreationError::OsError;
-use libc;
-
-use WindowAttributes;
-use os::macos::ActivationPolicy;
-use os::macos::WindowExt;
-
-use objc;
-use objc::runtime::{Class, Object, Sel, BOOL, YES, NO};
-use objc::declare::ClassDecl;
-
-use cocoa;
-use cocoa::appkit::{self, NSApplication, NSColor, NSScreen, NSView, NSWindow, NSWindowButton,
-    NSWindowStyleMask};
-use cocoa::base::{id, nil};
-use cocoa::foundation::{NSDictionary, NSPoint, NSRect, NSSize, NSString, NSAutoreleasePool};
-
-use core_graphics::display::CGDisplay;
-
 use std;
 use std::ops::Deref;
 use std::os::raw::c_void;
 use std::sync::Weak;
 use std::cell::{Cell, RefCell};
 
-use super::events_loop::{EventsLoop, Shared};
-use platform::platform::ffi;
-use platform::platform::util;
-use platform::platform::view::{new_view, set_ime_spot};
+use cocoa;
+use cocoa::appkit::{
+    self,
+    CGFloat,
+    NSApplication,
+    NSColor,
+    NSScreen,
+    NSView,
+    NSWindow,
+    NSWindowButton,
+    NSWindowStyleMask,
+};
+use cocoa::base::{id, nil};
+use cocoa::foundation::{NSAutoreleasePool, NSDictionary, NSPoint, NSRect, NSSize, NSString};
 
+use core_graphics::display::CGDisplay;
+
+use objc;
+use objc::runtime::{Class, Object, Sel, BOOL, YES, NO};
+use objc::declare::ClassDecl;
+
+use {
+    CreationError,
+    CursorState,
+    Event,
+    LogicalPosition,
+    LogicalSize,
+    MouseCursor,
+    WindowAttributes,
+    WindowEvent,
+    WindowId,
+};
+use CreationError::OsError;
+use os::macos::{ActivationPolicy, WindowExt};
+use platform::platform::{ffi, util};
+use platform::platform::events_loop::{EventsLoop, Shared};
+use platform::platform::view::{new_view, set_ime_spot};
 use window::MonitorId as RootMonitorId;
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Id(pub usize);
 
-struct DelegateState {
+pub struct DelegateState {
     view: IdRef,
     window: IdRef,
     shared: Weak<Shared>,
@@ -47,8 +59,11 @@ struct DelegateState {
     // see comments of `window_did_fail_to_enter_fullscreen`
     handle_with_fullscreen: bool,
 
-    // During windowDidResize, we use this to only send Moved if the position changed.
-    previous_position: Option<(i32, i32)>,
+    // During `windowDidResize`, we use this to only send Moved if the position changed.
+    previous_position: Option<(f64, f64)>,
+
+    // Used to prevent redundant events.
+    previous_dpi_factor: f64,
 }
 
 impl DelegateState {
@@ -150,48 +165,44 @@ pub struct WindowDelegate {
 }
 
 impl WindowDelegate {
+    // Emits an event via the `EventsLoop`'s callback or stores it in the pending queue.
+    pub fn emit_event(state: &mut DelegateState, window_event: WindowEvent) {
+        let window_id = get_window_id(*state.window);
+        let event = Event::WindowEvent {
+            window_id: WindowId(window_id),
+            event: window_event,
+        };
+        if let Some(shared) = state.shared.upgrade() {
+            shared.call_user_callback_with_event_or_store_in_pending(event);
+        }
+    }
+
+    pub fn emit_resize_event(state: &mut DelegateState) {
+        let rect = unsafe { NSView::frame(*state.view) };
+        let size = LogicalSize::new(rect.size.width as f64, rect.size.height as f64);
+        WindowDelegate::emit_event(state, WindowEvent::Resized(size));
+    }
+
+    pub fn emit_move_event(state: &mut DelegateState) {
+        let rect = unsafe { NSWindow::frame(*state.window) };
+        let x = rect.origin.x as f64;
+        let y = util::bottom_left_to_top_left(rect);
+        let moved = state.previous_position != Some((x, y));
+        if moved {
+            state.previous_position = Some((x, y));
+            WindowDelegate::emit_event(state, WindowEvent::Moved((x, y).into()));
+        }
+    }
+
     /// Get the delegate class, initiailizing it neccessary
     fn class() -> *const Class {
         use std::os::raw::c_void;
 
-        // Emits an event via the `EventsLoop`'s callback or stores it in the pending queue.
-        unsafe fn emit_event(state: &mut DelegateState, window_event: WindowEvent) {
-            let window_id = get_window_id(*state.window);
-            let event = Event::WindowEvent {
-                window_id: WindowId(window_id),
-                event: window_event,
-            };
-
-            if let Some(shared) = state.shared.upgrade() {
-                shared.call_user_callback_with_event_or_store_in_pending(event);
-            }
-        }
-
-        // Called when the window is resized or when the window was moved to a different screen.
-        unsafe fn emit_resize_event(state: &mut DelegateState) {
-            let rect = NSView::frame(*state.view);
-            let scale_factor = NSWindow::backingScaleFactor(*state.window) as f32;
-            let width = (scale_factor * rect.size.width as f32) as u32;
-            let height = (scale_factor * rect.size.height as f32) as u32;
-            emit_event(state, WindowEvent::Resized(width, height));
-        }
-
-        unsafe fn emit_move_event(state: &mut DelegateState) {
-            let frame_rect = NSWindow::frame(*state.window);
-            let x = frame_rect.origin.x as _;
-            let y = util::bottom_left_to_top_left(frame_rect);
-            let moved = state.previous_position != Some((x, y));
-            if moved {
-                state.previous_position = Some((x, y));
-                emit_event(state, WindowEvent::Moved(x, y));
-            }
-        }
-
         extern fn window_should_close(this: &Object, _: Sel, _: id) -> BOOL {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_event(state, WindowEvent::CloseRequested);
+                WindowDelegate::emit_event(state, WindowEvent::CloseRequested);
             }
             NO
         }
@@ -201,7 +212,7 @@ impl WindowDelegate {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
 
-                emit_event(state, WindowEvent::Destroyed);
+                WindowDelegate::emit_event(state, WindowEvent::Destroyed);
 
                 // Remove the window from the shared state.
                 if let Some(shared) = state.shared.upgrade() {
@@ -215,8 +226,8 @@ impl WindowDelegate {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_resize_event(state);
-                emit_move_event(state);
+                WindowDelegate::emit_resize_event(state);
+                WindowDelegate::emit_move_event(state);
             }
         }
 
@@ -225,7 +236,7 @@ impl WindowDelegate {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_move_event(state);
+                WindowDelegate::emit_move_event(state);
             }
         }
 
@@ -233,18 +244,26 @@ impl WindowDelegate {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_resize_event(state);
-                let scale_factor = NSWindow::backingScaleFactor(*state.window) as f32;
-                emit_event(state, WindowEvent::HiDPIFactorChanged(scale_factor));
+                let dpi_factor = NSWindow::backingScaleFactor(*state.window) as f64;
+                if state.previous_dpi_factor != dpi_factor {
+                    state.previous_dpi_factor = dpi_factor;
+                    WindowDelegate::emit_event(state, WindowEvent::HiDpiFactorChanged(dpi_factor));
+                    WindowDelegate::emit_resize_event(state);
+                }
             }
         }
 
+        // This will always be called before `window_did_change_screen`.
         extern fn window_did_change_backing_properties(this: &Object, _:Sel, _:id) {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                let scale_factor = NSWindow::backingScaleFactor(*state.window) as f32;
-                emit_event(state, WindowEvent::HiDPIFactorChanged(scale_factor));
+                let dpi_factor = NSWindow::backingScaleFactor(*state.window) as f64;
+                if state.previous_dpi_factor != dpi_factor {
+                    state.previous_dpi_factor = dpi_factor;
+                    WindowDelegate::emit_event(state, WindowEvent::HiDpiFactorChanged(dpi_factor));
+                    WindowDelegate::emit_resize_event(state);
+                }
             }
         }
 
@@ -254,7 +273,7 @@ impl WindowDelegate {
                 // lost focus
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_event(state, WindowEvent::Focused(true));
+                WindowDelegate::emit_event(state, WindowEvent::Focused(true));
             }
         }
 
@@ -262,7 +281,7 @@ impl WindowDelegate {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_event(state, WindowEvent::Focused(false));
+                WindowDelegate::emit_event(state, WindowEvent::Focused(false));
             }
         }
 
@@ -285,7 +304,7 @@ impl WindowDelegate {
 
                     let state: *mut c_void = *this.get_ivar("winitState");
                     let state = &mut *(state as *mut DelegateState);
-                    emit_event(state, WindowEvent::HoveredFile(PathBuf::from(path)));
+                    WindowDelegate::emit_event(state, WindowEvent::HoveredFile(PathBuf::from(path)));
                 }
             };
 
@@ -314,7 +333,7 @@ impl WindowDelegate {
 
                     let state: *mut c_void = *this.get_ivar("winitState");
                     let state = &mut *(state as *mut DelegateState);
-                    emit_event(state, WindowEvent::DroppedFile(PathBuf::from(path)));
+                    WindowDelegate::emit_event(state, WindowEvent::DroppedFile(PathBuf::from(path)));
                 }
             };
 
@@ -329,7 +348,7 @@ impl WindowDelegate {
             unsafe {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
-                emit_event(state, WindowEvent::HoveredFileCancelled);
+                WindowDelegate::emit_event(state, WindowEvent::HoveredFileCancelled);
             }
         }
 
@@ -500,7 +519,7 @@ pub struct PlatformSpecificWindowBuilderAttributes {
     pub titlebar_hidden: bool,
     pub titlebar_buttons_hidden: bool,
     pub fullsize_content_view: bool,
-    pub resize_increments: Option<(u32, u32)>,
+    pub resize_increments: Option<LogicalSize>,
 }
 
 pub struct Window2 {
@@ -617,12 +636,11 @@ impl Window2 {
 
             app.activateIgnoringOtherApps_(YES);
 
-            if let Some((width, height)) = win_attribs.min_dimensions {
-                nswindow_set_min_dimensions(window.0, width.into(), height.into());
+            if let Some(dimensions) = win_attribs.min_dimensions {
+                nswindow_set_min_dimensions(window.0, dimensions);
             }
-
-            if let Some((width, height)) = win_attribs.max_dimensions {
-                nswindow_set_max_dimensions(window.0, width.into(), height.into());
+            if let Some(dimensions) = win_attribs.max_dimensions {
+                nswindow_set_max_dimensions(window.0, dimensions);
             }
 
             use cocoa::foundation::NSArray;
@@ -631,7 +649,9 @@ impl Window2 {
                 registerForDraggedTypes:NSArray::arrayWithObject(nil, appkit::NSFilenamesPboardType)];
         }
 
-        let ds = DelegateState {
+        let dpi_factor = unsafe { NSWindow::backingScaleFactor(*window) as f64 };
+
+        let mut delegate_state = DelegateState {
             view: view.clone(),
             window: window.clone(),
             shared,
@@ -640,13 +660,19 @@ impl Window2 {
             save_style_mask: Cell::new(None),
             handle_with_fullscreen: win_attribs.fullscreen.is_some(),
             previous_position: None,
+            previous_dpi_factor: dpi_factor,
         };
-        ds.win_attribs.borrow_mut().fullscreen = None;
+        delegate_state.win_attribs.borrow_mut().fullscreen = None;
+
+        if dpi_factor != 1.0 {
+            WindowDelegate::emit_event(&mut delegate_state, WindowEvent::HiDpiFactorChanged(dpi_factor));
+            WindowDelegate::emit_resize_event(&mut delegate_state);
+        }
 
         let window = Window2 {
             view: view,
             window: window,
-            delegate: WindowDelegate::new(ds),
+            delegate: WindowDelegate::new(delegate_state),
             input_context,
         };
 
@@ -729,8 +755,10 @@ impl Window2 {
             let frame = match screen {
                 Some(screen) => appkit::NSScreen::frame(screen),
                 None => {
-                    let (width, height) = attrs.dimensions.unwrap_or((800, 600));
-                    NSRect::new(NSPoint::new(0., 0.), NSSize::new(width as f64, height as f64))
+                    let (width, height) = attrs.dimensions
+                        .map(|logical| (logical.width, logical.height))
+                        .unwrap_or((800.0, 600.0));
+                    NSRect::new(NSPoint::new(0.0, 0.0), NSSize::new(width, height))
                 }
             };
 
@@ -799,9 +827,10 @@ impl Window2 {
                     let _: () = msg_send![*window, setLevel:ffi::NSWindowLevel::NSFloatingWindowLevel];
                 }
 
-                if let Some((x, y)) = pl_attrs.resize_increments {
-                    if x >= 1 && y >= 1 {
-                        let size = NSSize::new(x as _, y as _);
+                if let Some(increments) = pl_attrs.resize_increments {
+                    let (x, y) = (increments.width, increments.height);
+                    if x >= 1.0 && y >= 1.0 {
+                        let size = NSSize::new(x as CGFloat, y as CGFloat);
                         window.setResizeIncrements_(size);
                     }
                 }
@@ -843,15 +872,15 @@ impl Window2 {
         unsafe { NSWindow::orderOut_(*self.window, nil); }
     }
 
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
         let frame_rect = unsafe { NSWindow::frame(*self.window) };
         Some((
-            frame_rect.origin.x as i32,
+            frame_rect.origin.x as f64,
             util::bottom_left_to_top_left(frame_rect),
-        ))
+        ).into())
     }
 
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
         let content_rect = unsafe {
             NSWindow::contentRectForFrameRect_(
                 *self.window,
@@ -859,18 +888,18 @@ impl Window2 {
             )
         };
         Some((
-            content_rect.origin.x as i32,
+            content_rect.origin.x as f64,
             util::bottom_left_to_top_left(content_rect),
-        ))
+        ).into())
     }
 
-    pub fn set_position(&self, x: i32, y: i32) {
+    pub fn set_position(&self, position: LogicalPosition) {
         let dummy = NSRect::new(
             NSPoint::new(
-                x as f64,
+                position.x,
                 // While it's true that we're setting the top-left position, it still needs to be
                 // in a bottom-left coordinate system.
-                CGDisplay::main().pixels_high() as f64 - y as f64,
+                CGDisplay::main().pixels_high() as f64 - position.y,
             ),
             NSSize::new(0f64, 0f64),
         );
@@ -880,42 +909,35 @@ impl Window2 {
     }
 
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
-        let factor = self.hidpi_factor() as f64; // API convention is that size is in physical pixels
-        unsafe {
-            let view_frame = NSView::frame(*self.view);
-            Some(((view_frame.size.width*factor) as u32, (view_frame.size.height*factor) as u32))
-        }
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
+        let view_frame = unsafe { NSView::frame(*self.view) };
+        Some((view_frame.size.width as f64, view_frame.size.height as f64).into())
     }
 
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
-        let factor = self.hidpi_factor() as f64; // API convention is that size is in physical pixels
-        unsafe {
-            let window_frame = NSWindow::frame(*self.window);
-            Some(((window_frame.size.width*factor) as u32, (window_frame.size.height*factor) as u32))
-        }
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
+        let view_frame = unsafe { NSWindow::frame(*self.window) };
+        Some((view_frame.size.width as f64, view_frame.size.height as f64).into())
     }
 
     #[inline]
-    pub fn set_inner_size(&self, width: u32, height: u32) {
-        let factor = self.hidpi_factor() as f64; // API convention is that size is in physical pixels
+    pub fn set_inner_size(&self, size: LogicalSize) {
         unsafe {
-            NSWindow::setContentSize_(*self.window, NSSize::new((width as f64)/factor, (height as f64)/factor));
+            NSWindow::setContentSize_(*self.window, NSSize::new(size.width as CGFloat, size.height as CGFloat));
         }
     }
 
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_min_dimensions(&self, dimensions: Option<LogicalSize>) {
         unsafe {
-            let (width, height) = dimensions.unwrap_or((0, 0));
-            nswindow_set_min_dimensions(self.window.0, width.into(), height.into());
+            let dimensions = dimensions.unwrap_or_else(|| (0, 0).into());
+            nswindow_set_min_dimensions(self.window.0, dimensions);
         }
     }
 
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_max_dimensions(&self, dimensions: Option<LogicalSize>) {
         unsafe {
-            let (width, height) = dimensions.unwrap_or((!0, !0));
-            nswindow_set_max_dimensions(self.window.0, width.into(), height.into());
+            let dimensions = dimensions.unwrap_or_else(|| (!0, !0).into());
+            nswindow_set_max_dimensions(self.window.0, dimensions);
         }
     }
 
@@ -934,16 +956,6 @@ impl Window2 {
         } // Otherwise, we don't change the mask until we exit fullscreen.
     }
 
-    #[inline]
-    pub fn platform_display(&self) -> *mut libc::c_void {
-        unimplemented!()
-    }
-
-    #[inline]
-    pub fn platform_window(&self) -> *mut libc::c_void {
-        *self.window as *mut libc::c_void
-    }
-
     pub fn set_cursor(&self, cursor: MouseCursor) {
         let cursor_name = match cursor {
             MouseCursor::Arrow | MouseCursor::Default => "arrowCursor",
@@ -1005,24 +1017,24 @@ impl Window2 {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         unsafe {
-            NSWindow::backingScaleFactor(*self.window) as f32
+            NSWindow::backingScaleFactor(*self.window) as f64
         }
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, x: i32, y: i32) -> Result<(), ()> {
-        let (window_x, window_y) = self.get_position().unwrap_or((0, 0));
-        let (cursor_x, cursor_y) = (window_x + x, window_y + y);
-
-        // TODO: Check for errors.
-        let _ = CGDisplay::warp_mouse_cursor_position(appkit::CGPoint {
-            x: cursor_x as appkit::CGFloat,
-            y: cursor_y as appkit::CGFloat,
-        });
-        let _ = CGDisplay::associate_mouse_and_mouse_cursor_position(true);
-
+    pub fn set_cursor_position(&self, cursor_position: LogicalPosition) -> Result<(), ()> {
+        let window_position = self.get_inner_position()
+            .expect("`get_inner_position` failed");
+        let point = appkit::CGPoint {
+            x: (cursor_position.x + window_position.x) as CGFloat,
+            y: (cursor_position.y + window_position.y) as CGFloat,
+        };
+        CGDisplay::warp_mouse_cursor_position(point)
+            .expect("`CGWarpMouseCursorPosition` failed");
+        CGDisplay::associate_mouse_and_mouse_cursor_position(true)
+            .expect("`CGAssociateMouseAndMouseCursorPosition` failed");
         Ok(())
     }
 
@@ -1131,8 +1143,8 @@ impl Window2 {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, x: i32, y: i32) {
-        set_ime_spot(*self.view, *self.input_context, x, y);
+    pub fn set_ime_spot(&self, logical_spot: LogicalPosition) {
+        set_ime_spot(*self.view, *self.input_context, logical_spot.x, logical_spot.y);
     }
 
     #[inline]
@@ -1149,51 +1161,50 @@ pub fn get_window_id(window_cocoa_id: id) -> Id {
     Id(window_cocoa_id as *const objc::runtime::Object as usize)
 }
 
-unsafe fn nswindow_set_min_dimensions<V: NSWindow + Copy>(
-    window: V, min_width: f64, min_height: f64)
-{
+unsafe fn nswindow_set_min_dimensions<V: NSWindow + Copy>(window: V, mut min_size: LogicalSize) {
+    let mut current_rect = NSWindow::frame(window);
+    let content_rect = NSWindow::contentRectForFrameRect_(window, NSWindow::frame(window));
+    // Convert from client area size to window size
+    min_size.width += (current_rect.size.width - content_rect.size.width) as f64; // this tends to be 0
+    min_size.height += (current_rect.size.height - content_rect.size.height) as f64;
     window.setMinSize_(NSSize {
-        width: min_width,
-        height: min_height,
+        width: min_size.width as CGFloat,
+        height: min_size.height as CGFloat,
     });
     // If necessary, resize the window to match constraint
-    let mut current_rect = NSWindow::frame(window);
-    if current_rect.size.width < min_width {
-        current_rect.size.width = min_width;
+    if current_rect.size.width < min_size.width {
+        current_rect.size.width = min_size.width;
         window.setFrame_display_(current_rect, 0)
     }
-    if current_rect.size.height < min_height {
-        // The origin point of a rectangle is at its bottom left in Cocoa. To
-        // ensure the window's top-left point remains the same:
-        current_rect.origin.y +=
-            current_rect.size.height - min_height;
-
-        current_rect.size.height = min_height;
+    if current_rect.size.height < min_size.height {
+        // The origin point of a rectangle is at its bottom left in Cocoa.
+        // To ensure the window's top-left point remains the same:
+        current_rect.origin.y += current_rect.size.height - min_size.height;
+        current_rect.size.height = min_size.height;
         window.setFrame_display_(current_rect, 0)
     }
 }
 
-unsafe fn nswindow_set_max_dimensions<V: NSWindow + Copy>(
-    window: V, max_width: f64, max_height: f64)
-{
+unsafe fn nswindow_set_max_dimensions<V: NSWindow + Copy>(window: V, mut max_size: LogicalSize) {
+    let mut current_rect = NSWindow::frame(window);
+    let content_rect = NSWindow::contentRectForFrameRect_(window, NSWindow::frame(window));
+    // Convert from client area size to window size
+    max_size.width += (current_rect.size.width - content_rect.size.width) as f64; // this tends to be 0
+    max_size.height += (current_rect.size.height - content_rect.size.height) as f64;
     window.setMaxSize_(NSSize {
-        width: max_width,
-        height: max_height,
+        width: max_size.width as CGFloat,
+        height: max_size.height as CGFloat,
     });
     // If necessary, resize the window to match constraint
-    let mut current_rect = NSWindow::frame(window);
-    if current_rect.size.width > max_width {
-        current_rect.size.width = max_width;
+    if current_rect.size.width > max_size.width {
+        current_rect.size.width = max_size.width;
         window.setFrame_display_(current_rect, 0)
     }
-    if current_rect.size.height > max_height {
-        // The origin point of a rectangle is at its bottom left in
-        // Cocoa. To ensure the window's top-left point remains the
-        // same:
-        current_rect.origin.y +=
-            current_rect.size.height - max_height;
-
-        current_rect.size.height = max_height;
+    if current_rect.size.height > max_size.height {
+        // The origin point of a rectangle is at its bottom left in Cocoa.
+        // To ensure the window's top-left point remains the same:
+        current_rect.origin.y += current_rect.size.height - max_size.height;
+        current_rect.size.height = max_size.height;
         window.setFrame_display_(current_rect, 0)
     }
 }

src/platform/windows/dpi.rs

@@ -0,0 +1,196 @@
+#![allow(non_snake_case, unused_unsafe)]
+
+use std::mem;
+use std::os::raw::c_void;
+use std::sync::{Once, ONCE_INIT};
+
+use winapi::shared::minwindef::{BOOL, UINT, FALSE};
+use winapi::shared::windef::{
+    DPI_AWARENESS_CONTEXT,
+    DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE,
+    HDC,
+    HMONITOR,
+    HWND,
+};
+use winapi::shared::winerror::S_OK;
+use winapi::um::libloaderapi::{GetProcAddress, LoadLibraryA};
+use winapi::um::shellscalingapi::{
+    MDT_EFFECTIVE_DPI,
+    MONITOR_DPI_TYPE,
+    PROCESS_DPI_AWARENESS,
+    PROCESS_PER_MONITOR_DPI_AWARE,
+};
+use winapi::um::wingdi::{GetDeviceCaps, LOGPIXELSX};
+use winapi::um::winnt::{HRESULT, LPCSTR};
+use winapi::um::winuser::{self, MONITOR_DEFAULTTONEAREST};
+
+const DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2: DPI_AWARENESS_CONTEXT = -4isize as _;
+
+type SetProcessDPIAware = unsafe extern "system" fn () -> BOOL;
+type SetProcessDpiAwareness = unsafe extern "system" fn (
+    value: PROCESS_DPI_AWARENESS,
+) -> HRESULT;
+type SetProcessDpiAwarenessContext = unsafe extern "system" fn (
+    value: DPI_AWARENESS_CONTEXT,
+) -> BOOL;
+type GetDpiForWindow = unsafe extern "system" fn (hwnd: HWND) -> UINT;
+type GetDpiForMonitor = unsafe extern "system" fn (
+    hmonitor: HMONITOR,
+    dpi_type: MONITOR_DPI_TYPE,
+    dpi_x: *mut UINT,
+    dpi_y: *mut UINT,
+) -> HRESULT;
+type EnableNonClientDpiScaling = unsafe extern "system" fn (hwnd: HWND) -> BOOL;
+
+// Helper function to dynamically load function pointer.
+// `library` and `function` must be zero-terminated.
+fn get_function_impl(library: &str, function: &str) -> Option<*const c_void> {
+    assert_eq!(library.chars().last(), Some('\0'));
+    assert_eq!(function.chars().last(), Some('\0'));
+
+    // Library names we will use are ASCII so we can use the A version to avoid string conversion.
+    let module = unsafe { LoadLibraryA(library.as_ptr() as LPCSTR) };
+    if module.is_null() {
+        return None;
+    }
+
+    let function_ptr = unsafe { GetProcAddress(module, function.as_ptr() as LPCSTR) };
+    if function_ptr.is_null() {
+        return None;
+    }
+
+    Some(function_ptr as _)
+}
+
+macro_rules! get_function {
+    ($lib:expr, $func:ident) => {
+        get_function_impl(concat!($lib, '\0'), concat!(stringify!($func), '\0'))
+            .map(|f| unsafe { mem::transmute::<*const _, $func>(f) })
+    }
+}
+
+lazy_static! {
+    static ref GET_DPI_FOR_WINDOW: Option<GetDpiForWindow> = get_function!(
+        "user32.dll",
+        GetDpiForWindow
+    );
+    static ref GET_DPI_FOR_MONITOR: Option<GetDpiForMonitor> = get_function!(
+        "shcore.dll",
+        GetDpiForMonitor
+    );
+    static ref ENABLE_NON_CLIENT_DPI_SCALING: Option<EnableNonClientDpiScaling> = get_function!(
+        "user32.dll",
+        EnableNonClientDpiScaling
+    );
+}
+
+pub fn become_dpi_aware(enable: bool) {
+    if !enable { return; }
+    static ENABLE_DPI_AWARENESS: Once = ONCE_INIT;
+    ENABLE_DPI_AWARENESS.call_once(|| { unsafe {
+        if let Some(SetProcessDpiAwarenessContext) = get_function!(
+            "user32.dll",
+            SetProcessDpiAwarenessContext
+        ) {
+            // We are on Windows 10 Anniversary Update (1607) or later.
+            if SetProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2)
+            == FALSE {
+                // V2 only works with Windows 10 Creators Update (1703). Try using the older
+                // V1 if we can't set V2.
+                SetProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE);
+            }
+        } else if let Some(SetProcessDpiAwareness) = get_function!(
+            "shcore.dll",
+            SetProcessDpiAwareness
+        ) {
+            // We are on Windows 8.1 or later.
+            SetProcessDpiAwareness(PROCESS_PER_MONITOR_DPI_AWARE);
+        } else if let Some(SetProcessDPIAware) = get_function!(
+            "user32.dll",
+            SetProcessDPIAware
+        ) {
+            // We are on Vista or later.
+            SetProcessDPIAware();
+        }
+    } });
+}
+
+pub fn enable_non_client_dpi_scaling(hwnd: HWND) {
+    unsafe {
+        if let Some(EnableNonClientDpiScaling) = *ENABLE_NON_CLIENT_DPI_SCALING {
+            EnableNonClientDpiScaling(hwnd);
+        }
+    }
+}
+
+pub fn get_monitor_dpi(hmonitor: HMONITOR) -> Option<u32> {
+    unsafe {
+        if let Some(GetDpiForMonitor) = *GET_DPI_FOR_MONITOR {
+            // We are on Windows 8.1 or later.
+            let mut dpi_x = 0;
+            let mut dpi_y = 0;
+            if GetDpiForMonitor(hmonitor, MDT_EFFECTIVE_DPI, &mut dpi_x, &mut dpi_y) == S_OK {
+                // MSDN says that "the values of *dpiX and *dpiY are identical. You only need to
+                // record one of the values to determine the DPI and respond appropriately".
+                // https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510(v=vs.85).aspx
+                return Some(dpi_x as u32)
+            }
+        }
+    }
+    None
+}
+
+pub const BASE_DPI: u32 = 96;
+pub fn dpi_to_scale_factor(dpi: u32) -> f64 {
+    dpi as f64 / BASE_DPI as f64
+}
+
+pub unsafe fn get_window_dpi(hwnd: HWND, hdc: HDC) -> u32 {
+    if let Some(GetDpiForWindow) = *GET_DPI_FOR_WINDOW {
+        // We are on Windows 10 Anniversary Update (1607) or later.
+        match GetDpiForWindow(hwnd) {
+            0 => BASE_DPI, // 0 is returned if hwnd is invalid
+            dpi => dpi as u32,
+        }
+    } else if let Some(GetDpiForMonitor) = *GET_DPI_FOR_MONITOR {
+        // We are on Windows 8.1 or later.
+        let monitor = winuser::MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);
+        if monitor.is_null() {
+            return BASE_DPI;
+        }
+
+        let mut dpi_x = 0;
+        let mut dpi_y = 0;
+        if GetDpiForMonitor(monitor, MDT_EFFECTIVE_DPI, &mut dpi_x, &mut dpi_y) == S_OK {
+            dpi_x as u32
+        } else {
+            BASE_DPI
+        }
+    } else {
+        // We are on Vista or later.
+        if winuser::IsProcessDPIAware() != FALSE {
+            // If the process is DPI aware, then scaling must be handled by the application using
+            // this DPI value.
+            GetDeviceCaps(hdc, LOGPIXELSX) as u32
+        } else {
+            // If the process is DPI unaware, then scaling is performed by the OS; we thus return
+            // 96 (scale factor 1.0) to prevent the window from being re-scaled by both the
+            // application and the WM.
+            BASE_DPI
+        }
+    }
+}
+
+// Use this when you have both the HWND and HDC on hand (i.e. window methods)
+pub fn get_window_scale_factor(hwnd: HWND, hdc: HDC) -> f64 {
+    dpi_to_scale_factor(unsafe { get_window_dpi(hwnd, hdc) })
+}
+
+// Use this when you only have the HWND (i.e. event handling)
+pub fn get_hwnd_scale_factor(hwnd: HWND) -> f64 {
+    let hdc = unsafe { winuser::GetDC(hwnd) };
+    if hdc.is_null() {
+        panic!("[winit] `GetDC` returned null!");
+    }
+    unsafe { get_window_scale_factor(hwnd, hdc) }
+}

src/platform/windows/events_loop.rs

@@ -12,42 +12,56 @@
 //! The closure passed to the `execute_in_thread` method takes an `Inserter` that you can use to
 //! add a `WindowState` entry to a list of window to be used by the callback.
 
+use std::{mem, ptr, thread};
 use std::cell::RefCell;
 use std::collections::HashMap;
 use std::ffi::OsString;
-use std::mem;
 use std::os::windows::ffi::OsStringExt;
 use std::os::windows::io::AsRawHandle;
-use std::ptr;
-use std::sync::mpsc;
-use std::sync::Arc;
-use std::sync::Barrier;
-use std::sync::Mutex;
-use std::sync::Condvar;
-use std::thread;
+use std::sync::{Arc, Barrier, Condvar, mpsc, Mutex};
 
-use winapi::shared::minwindef::{LOWORD, HIWORD, DWORD, WPARAM, LPARAM, INT, UINT, LRESULT, MAX_PATH};
+use winapi::ctypes::c_int;
+use winapi::shared::minwindef::{
+    BOOL,
+    DWORD,
+    HIWORD,
+    INT,
+    LOWORD,
+    LPARAM,
+    LRESULT,
+    MAX_PATH,
+    UINT,
+    WPARAM,
+};
 use winapi::shared::windef::{HWND, POINT, RECT};
 use winapi::shared::windowsx;
 use winapi::um::{winuser, shellapi, processthreadsapi};
-use winapi::um::winnt::{LONG, SHORT};
+use winapi::um::winnt::{LONG, LPCSTR, SHORT};
 
-use events::DeviceEvent;
+use {
+    ControlFlow,
+    CursorState,
+    Event,
+    EventsLoopClosed,
+    KeyboardInput,
+    LogicalPosition,
+    LogicalSize,
+    PhysicalSize,
+    WindowEvent,
+    WindowId as SuperWindowId,
+};
+use events::{DeviceEvent, Touch, TouchPhase};
 use platform::platform::{event, Cursor, WindowId, DEVICE_ID, wrap_device_id, util};
+use platform::platform::dpi::{
+    become_dpi_aware,
+    dpi_to_scale_factor,
+    enable_non_client_dpi_scaling,
+    get_hwnd_scale_factor,
+};
 use platform::platform::event::{handle_extended_keys, process_key_params, vkey_to_winit_vkey};
-use platform::platform::raw_input::*;
+use platform::platform::raw_input::{get_raw_input_data, get_raw_mouse_button_state};
 use platform::platform::window::adjust_size;
 
-use ControlFlow;
-use CursorState;
-use Event;
-use EventsLoopClosed;
-use KeyboardInput;
-use WindowAttributes;
-use WindowEvent;
-use WindowId as SuperWindowId;
-use events::{Touch, TouchPhase};
-
 /// Contains saved window info for switching between fullscreen
 #[derive(Clone)]
 pub struct SavedWindowInfo {
@@ -57,6 +71,11 @@ pub struct SavedWindowInfo {
     pub ex_style: LONG,
     /// Window position and size
     pub rect: RECT,
+    // Since a window can be fullscreened to a different monitor, a DPI change can be triggered. This could result in
+    // the window being automitcally resized to smaller/larger than it was supposed to be restored to, so we thus must
+    // check if the post-fullscreen DPI matches the pre-fullscreen DPI.
+    pub is_fullscreen: bool,
+    pub dpi_factor: Option<f64>,
 }
 
 /// Contains information about states and the window that the callback is going to use.
@@ -67,11 +86,28 @@ pub struct WindowState {
     /// Cursor state to set at the next `WM_SETCURSOR` event received.
     pub cursor_state: CursorState,
     /// Used by `WM_GETMINMAXINFO`.
-    pub attributes: WindowAttributes,
+    pub max_size: Option<PhysicalSize>,
+    pub min_size: Option<PhysicalSize>,
     /// Will contain `true` if the mouse is hovering the window.
     pub mouse_in_window: bool,
     /// Saved window info for fullscreen restored
     pub saved_window_info: Option<SavedWindowInfo>,
+    // This is different from the value in `SavedWindowInfo`! That one represents the DPI saved upon entering
+    // fullscreen. This will always be the most recent DPI for the window.
+    pub dpi_factor: f64,
+}
+
+impl WindowState {
+    pub fn update_min_max(&mut self, old_dpi_factor: f64, new_dpi_factor: f64) {
+        let scale_factor = new_dpi_factor / old_dpi_factor;
+        let dpi_adjuster = |mut physical_size: PhysicalSize| -> PhysicalSize {
+            physical_size.width *= scale_factor;
+            physical_size.height *= scale_factor;
+            physical_size
+        };
+        self.max_size = self.max_size.map(&dpi_adjuster);
+        self.min_size = self.min_size.map(&dpi_adjuster);
+    }
 }
 
 /// Dummy object that allows inserting a window's state.
@@ -98,11 +134,17 @@ pub struct EventsLoop {
     // Variable that contains the block state of the win32 event loop thread during a WM_SIZE event.
     // The mutex's value is `true` when it's blocked, and should be set to false when it's done
     // blocking. That's done by the parent thread when it receives a Resized event.
-    win32_block_loop: Arc<(Mutex<bool>, Condvar)>
+    win32_block_loop: Arc<(Mutex<bool>, Condvar)>,
 }
 
 impl EventsLoop {
     pub fn new() -> EventsLoop {
+        Self::with_dpi_awareness(true)
+    }
+
+    pub fn with_dpi_awareness(dpi_aware: bool) -> EventsLoop {
+        become_dpi_aware(dpi_aware);
+
         // The main events transfer channel.
         let (tx, rx) = mpsc::channel();
         let win32_block_loop = Arc::new((Mutex::new(false), Condvar::new()));
@@ -171,7 +213,7 @@ impl EventsLoop {
         EventsLoop {
             thread_id,
             receiver: rx,
-            win32_block_loop
+            win32_block_loop,
         }
     }
 
@@ -289,22 +331,21 @@ impl EventsLoopProxy {
     where
         F: FnMut(Inserter) + Send + 'static,
     {
-        unsafe {
-            // We are using double-boxing here because it make casting back much easier
-            let boxed = Box::new(function) as Box<FnMut(_)>;
-            let boxed2 = Box::new(boxed);
-            let raw = Box::into_raw(boxed2);
+        // We are using double-boxing here because it make casting back much easier
+        let double_box = Box::new(Box::new(function) as Box<FnMut(_)>);
+        let raw = Box::into_raw(double_box);
 
-            let res = winuser::PostThreadMessageA(
+        let res = unsafe {
+            winuser::PostThreadMessageA(
                 self.thread_id,
                 *EXEC_MSG_ID,
                 raw as *mut () as usize as WPARAM,
                 0,
-            );
-            // PostThreadMessage can only fail if the thread ID is invalid (which shouldn't happen
-            // as the events loop is still alive) or if the queue is full.
-            assert!(res != 0, "PostThreadMessage failed; is the messages queue full?");
-        }
+            )
+        };
+        // PostThreadMessage can only fail if the thread ID is invalid (which shouldn't happen as
+        // the events loop is still alive) or if the queue is full.
+        assert!(res != 0, "PostThreadMessage failed; is the messages queue full?");
     }
 }
 
@@ -313,7 +354,7 @@ lazy_static! {
     // WPARAM and LPARAM are unused.
     static ref WAKEUP_MSG_ID: u32 = {
         unsafe {
-            winuser::RegisterWindowMessageA("Winit::WakeupMsg\0".as_ptr() as *const i8)
+            winuser::RegisterWindowMessageA("Winit::WakeupMsg\0".as_ptr() as LPCSTR)
         }
     };
     // Message sent when we want to execute a closure in the thread.
@@ -321,14 +362,21 @@ lazy_static! {
     // and LPARAM is unused.
     static ref EXEC_MSG_ID: u32 = {
         unsafe {
-            winuser::RegisterWindowMessageA("Winit::ExecMsg\0".as_ptr() as *const i8)
+            winuser::RegisterWindowMessageA("Winit::ExecMsg\0".as_ptr() as LPCSTR)
         }
     };
     // Message sent by a `Window` when it wants to be destroyed by the main thread.
     // WPARAM and LPARAM are unused.
     pub static ref DESTROY_MSG_ID: u32 = {
         unsafe {
-            winuser::RegisterWindowMessageA("Winit::DestroyMsg\0".as_ptr() as *const i8)
+            winuser::RegisterWindowMessageA("Winit::DestroyMsg\0".as_ptr() as LPCSTR)
+        }
+    };
+    // Message sent by a `Window` after creation if it has a DPI != 96.
+    // WPARAM is the the DPI (u32). LOWORD of LPARAM is width, and HIWORD is height.
+    pub static ref INITIAL_DPI_MSG_ID: u32 = {
+        unsafe {
+            winuser::RegisterWindowMessageA("Winit::InitialDpiMsg\0".as_ptr() as LPCSTR)
         }
     };
 }
@@ -385,11 +433,18 @@ unsafe fn release_mouse() {
 //
 // Returning 0 tells the Win32 API that the message has been processed.
 // FIXME: detect WM_DWMCOMPOSITIONCHANGED and call DwmEnableBlurBehindWindow if necessary
-pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
-                                       wparam: WPARAM, lparam: LPARAM)
-                                       -> LRESULT
-{
+pub unsafe extern "system" fn callback(
+    window: HWND,
+    msg: UINT,
+    wparam: WPARAM,
+    lparam: LPARAM,
+) -> LRESULT {
     match msg {
+        winuser::WM_NCCREATE => {
+            enable_non_client_dpi_scaling(window);
+            winuser::DefWindowProcW(window, msg, wparam, lparam)
+        },
+
         winuser::WM_CLOSE => {
             use events::WindowEvent::CloseRequested;
             send_event(Event::WindowEvent {
@@ -427,9 +482,14 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
 
             let windowpos = lparam as *const winuser::WINDOWPOS;
             if (*windowpos).flags & winuser::SWP_NOMOVE != winuser::SWP_NOMOVE {
+                let dpi_factor = get_hwnd_scale_factor(window);
+                let logical_position = LogicalPosition::from_physical(
+                    ((*windowpos).x, (*windowpos).y),
+                    dpi_factor,
+                );
                 send_event(Event::WindowEvent {
                     window_id: SuperWindowId(WindowId(window)),
-                    event: Moved((*windowpos).x, (*windowpos).y),
+                    event: Moved(logical_position),
                 });
             }
 
@@ -448,9 +508,11 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
                 let mut context_stash = context_stash.borrow_mut();
                 let cstash = context_stash.as_mut().unwrap();
 
+                let dpi_factor = get_hwnd_scale_factor(window);
+                let logical_size = LogicalSize::from_physical((w, h), dpi_factor);
                 let event = Event::WindowEvent {
                     window_id: SuperWindowId(WindowId(window)),
-                    event: Resized(w, h),
+                    event: Resized(logical_size),
                 };
 
                 // If this window has been inserted into the window map, the resize event happened
@@ -528,10 +590,12 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
 
             let x = windowsx::GET_X_LPARAM(lparam) as f64;
             let y = windowsx::GET_Y_LPARAM(lparam) as f64;
+            let dpi_factor = get_hwnd_scale_factor(window);
+            let position = LogicalPosition::from_physical((x, y), dpi_factor);
 
             send_event(Event::WindowEvent {
                 window_id: SuperWindowId(WindowId(window)),
-                event: CursorMoved { device_id: DEVICE_ID, position: (x, y), modifiers: event::get_key_mods() },
+                event: CursorMoved { device_id: DEVICE_ID, position, modifiers: event::get_key_mods() },
             });
 
             0
@@ -869,10 +933,17 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
             let mut inputs = Vec::with_capacity( pcount );
             inputs.set_len( pcount );
             let htouch = lparam as winuser::HTOUCHINPUT;
-            if winuser::GetTouchInputInfo( htouch, pcount as UINT,
-                                           inputs.as_mut_ptr(),
-                                           mem::size_of::<winuser::TOUCHINPUT>() as INT ) > 0 {
+            if winuser::GetTouchInputInfo(
+                htouch,
+                pcount as UINT,
+                inputs.as_mut_ptr(),
+                mem::size_of::<winuser::TOUCHINPUT>() as INT,
+            ) > 0 {
+                let dpi_factor = get_hwnd_scale_factor(window);
                 for input in &inputs {
+                    let x = (input.x as f64) / 100f64;
+                    let y = (input.y as f64) / 100f64;
+                    let location = LogicalPosition::from_physical((x, y), dpi_factor);
                     send_event( Event::WindowEvent {
                         window_id: SuperWindowId(WindowId(window)),
                         event: WindowEvent::Touch(Touch {
@@ -886,8 +957,7 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
                             } else {
                                 continue;
                             },
-                            location: ((input.x as f64) / 100f64,
-                                       (input.y as f64) / 100f64),
+                            location,
                             id: input.dwID as u64,
                             device_id: DEVICE_ID,
                         })
@@ -907,11 +977,14 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
 
             let x = windowsx::GET_X_LPARAM(lparam) as f64;
             let y = windowsx::GET_Y_LPARAM(lparam) as f64;
+            let dpi_factor = get_hwnd_scale_factor(window);
+            let position = LogicalPosition::from_physical((x, y), dpi_factor);
 
             send_event(Event::WindowEvent {
                 window_id: SuperWindowId(WindowId(window)),
-                event: CursorMoved { device_id: DEVICE_ID, position: (x, y), modifiers: event::get_key_mods() },
+                event: CursorMoved { device_id: DEVICE_ID, position, modifiers: event::get_key_mods() },
             });
+
             0
         },
 
@@ -985,18 +1058,15 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
                     if let Some(wstash) = cstash.windows.get(&window) {
                         let window_state = wstash.lock().unwrap();
 
-                        if window_state.attributes.min_dimensions.is_some() ||
-                           window_state.attributes.max_dimensions.is_some() {
-
+                        if window_state.min_size.is_some() || window_state.max_size.is_some() {
                             let style = winuser::GetWindowLongA(window, winuser::GWL_STYLE) as DWORD;
                             let ex_style = winuser::GetWindowLongA(window, winuser::GWL_EXSTYLE) as DWORD;
-
-                            if let Some(min_dimensions) = window_state.attributes.min_dimensions {
-                                let (width, height) = adjust_size(min_dimensions, style, ex_style);
+                            if let Some(min_size) = window_state.min_size {
+                                let (width, height) = adjust_size(min_size, style, ex_style);
                                 (*mmi).ptMinTrackSize = POINT { x: width as i32, y: height as i32 };
                             }
-                            if let Some(max_dimensions) = window_state.attributes.max_dimensions {
-                                let (width, height) = adjust_size(max_dimensions, style, ex_style);
+                            if let Some(max_size) = window_state.max_size {
+                                let (width, height) = adjust_size(max_size, style, ex_style);
                                 (*mmi).ptMaxTrackSize = POINT { x: width as i32, y: height as i32 };
                             }
                         }
@@ -1007,10 +1077,115 @@ pub unsafe extern "system" fn callback(window: HWND, msg: UINT,
             0
         },
 
+        // Only sent on Windows 8.1 or newer. On Windows 7 and older user has to log out to change
+        // DPI, therefore all applications are closed while DPI is changing.
+        winuser::WM_DPICHANGED => {
+            use events::WindowEvent::HiDpiFactorChanged;
+
+            // This message actually provides two DPI values - x and y. However MSDN says that
+            // "you only need to use either the X-axis or the Y-axis value when scaling your
+            // application since they are the same".
+            // https://msdn.microsoft.com/en-us/library/windows/desktop/dn312083(v=vs.85).aspx
+            let new_dpi_x = u32::from(LOWORD(wparam as DWORD));
+            let new_dpi_factor = dpi_to_scale_factor(new_dpi_x);
+
+            let suppress_resize = CONTEXT_STASH.with(|context_stash| {
+                context_stash
+                    .borrow()
+                    .as_ref()
+                    .and_then(|cstash| cstash.windows.get(&window))
+                    .map(|window_state_mutex| {
+                        let mut window_state = window_state_mutex.lock().unwrap();
+                        let suppress_resize = window_state.saved_window_info
+                            .as_mut()
+                            .map(|saved_window_info| {
+                                let dpi_changed = if !saved_window_info.is_fullscreen {
+                                    saved_window_info.dpi_factor.take() != Some(new_dpi_factor)
+                                } else {
+                                    false
+                                };
+                                !dpi_changed || saved_window_info.is_fullscreen
+                            })
+                            .unwrap_or(false);
+                        // Now we adjust the min/max dimensions for the new DPI.
+                        if !suppress_resize {
+                            let old_dpi_factor = window_state.dpi_factor;
+                            window_state.update_min_max(old_dpi_factor, new_dpi_factor);
+                        }
+                        window_state.dpi_factor = new_dpi_factor;
+                        suppress_resize
+                    })
+                    .unwrap_or(false)
+            });
+
+            // This prevents us from re-applying DPI adjustment to the restored size after exiting
+            // fullscreen (the restored size is already DPI adjusted).
+            if !suppress_resize {
+                // Resize window to the size suggested by Windows.
+                let rect = &*(lparam as *const RECT);
+                winuser::SetWindowPos(
+                    window,
+                    ptr::null_mut(),
+                    rect.left,
+                    rect.top,
+                    rect.right - rect.left,
+                    rect.bottom - rect.top,
+                    winuser::SWP_NOZORDER | winuser::SWP_NOACTIVATE,
+                );
+            }
+
+            send_event(Event::WindowEvent {
+                window_id: SuperWindowId(WindowId(window)),
+                event: HiDpiFactorChanged(new_dpi_factor),
+            });
+
+            0
+        },
+
         _ => {
             if msg == *DESTROY_MSG_ID {
                 winuser::DestroyWindow(window);
                 0
+            } else if msg == *INITIAL_DPI_MSG_ID {
+                use events::WindowEvent::HiDpiFactorChanged;
+                let scale_factor = dpi_to_scale_factor(wparam as u32);
+                send_event(Event::WindowEvent {
+                    window_id: SuperWindowId(WindowId(window)),
+                    event: HiDpiFactorChanged(scale_factor),
+                });
+                // Automatically resize for actual DPI
+                let width = LOWORD(lparam as DWORD) as u32;
+                let height = HIWORD(lparam as DWORD) as u32;
+                let (adjusted_width, adjusted_height): (u32, u32) = PhysicalSize::from_logical(
+                    (width, height),
+                    scale_factor,
+                ).into();
+                // We're not done yet! `SetWindowPos` needs the window size, not the client area size.
+                let mut rect = RECT {
+                    top: 0,
+                    left: 0,
+                    bottom: adjusted_height as LONG,
+                    right: adjusted_width as LONG,
+                };
+                let dw_style = winuser::GetWindowLongA(window, winuser::GWL_STYLE) as DWORD;
+                let b_menu = !winuser::GetMenu(window).is_null() as BOOL;
+                let dw_style_ex = winuser::GetWindowLongA(window, winuser::GWL_EXSTYLE) as DWORD;
+                winuser::AdjustWindowRectEx(&mut rect, dw_style, b_menu, dw_style_ex);
+                let outer_x = (rect.right - rect.left).abs() as c_int;
+                let outer_y = (rect.top - rect.bottom).abs() as c_int;
+                winuser::SetWindowPos(
+                    window,
+                    ptr::null_mut(),
+                    0,
+                    0,
+                    outer_x,
+                    outer_y,
+                    winuser::SWP_NOMOVE
+                    | winuser::SWP_NOREPOSITION
+                    | winuser::SWP_NOZORDER
+                    | winuser::SWP_NOACTIVATE,
+                );
+                0
             } else {
                 winuser::DefWindowProcW(window, msg, wparam, lparam)
             }

src/platform/windows/mod.rs

@@ -47,6 +47,7 @@ pub struct WindowId(HWND);
 unsafe impl Send for WindowId {}
 unsafe impl Sync for WindowId {}
 
+mod dpi;
 mod event;
 mod events_loop;
 mod icon;

src/platform/windows/monitor.rs

@@ -1,38 +1,31 @@
-use winapi::ctypes::wchar_t;
-use winapi::shared::minwindef::{DWORD, LPARAM, BOOL, TRUE};
-use winapi::shared::windef::{HMONITOR, HDC, LPRECT, HWND};
+use winapi::shared::minwindef::{BOOL, DWORD, LPARAM, TRUE};
+use winapi::shared::windef::{HDC, HMONITOR, HWND, LPRECT, POINT};
 use winapi::um::winuser;
 
-use std::collections::VecDeque;
 use std::{mem, ptr};
+use std::collections::VecDeque;
 
+use {PhysicalPosition, PhysicalSize};
 use super::{EventsLoop, util};
+use platform::platform::dpi::{dpi_to_scale_factor, get_monitor_dpi};
 
 /// Win32 implementation of the main `MonitorId` object.
 #[derive(Debug, Clone)]
 pub struct MonitorId {
-    /// The system name of the adapter.
-    adapter_name: [wchar_t; 32],
-
     /// Monitor handle.
     hmonitor: HMonitor,
-
     /// The system name of the monitor.
     monitor_name: String,
-
     /// True if this is the primary monitor.
     primary: bool,
-
     /// The position of the monitor in pixels on the desktop.
     ///
     /// A window that is positioned at these coordinates will overlap the monitor.
     position: (i32, i32),
-
     /// The current resolution in pixels on the monitor.
     dimensions: (u32, u32),
-
-    /// DPI scaling factor.
-    hidpi_factor: f32,
+    /// DPI scale factor.
+    hidpi_factor: f64,
 }
 
 // Send is not implemented for HMONITOR, we have to wrap it and implement it manually.
@@ -44,122 +37,109 @@ struct HMonitor(HMONITOR);
 
 unsafe impl Send for HMonitor {}
 
-unsafe extern "system" fn monitor_enum_proc(hmonitor: HMONITOR, _: HDC, place: LPRECT, data: LPARAM) -> BOOL {
+unsafe extern "system" fn monitor_enum_proc(
+    hmonitor: HMONITOR,
+    _hdc: HDC,
+    _place: LPRECT,
+    data: LPARAM,
+) -> BOOL {
     let monitors = data as *mut VecDeque<MonitorId>;
-
-    let place = *place;
-    let position = (place.left as i32, place.top as i32);
-    let dimensions = ((place.right - place.left) as u32, (place.bottom - place.top) as u32);
-
-    let mut monitor_info: winuser::MONITORINFOEXW = mem::zeroed();
-    monitor_info.cbSize = mem::size_of::<winuser::MONITORINFOEXW>() as DWORD;
-    if winuser::GetMonitorInfoW(hmonitor, &mut monitor_info as *mut winuser::MONITORINFOEXW as *mut winuser::MONITORINFO) == 0 {
-        // Some error occurred, just skip this monitor and go on.
-        return TRUE;
-    }
-
-    (*monitors).push_back(MonitorId {
-        adapter_name: monitor_info.szDevice,
-        hmonitor: HMonitor(hmonitor),
-        monitor_name: util::wchar_to_string(&monitor_info.szDevice),
-        primary: monitor_info.dwFlags & winuser::MONITORINFOF_PRIMARY != 0,
-        position,
-        dimensions,
-        hidpi_factor: 1.0,
-    });
-
-    // TRUE means continue enumeration.
-    TRUE
+    (*monitors).push_back(MonitorId::from_hmonitor(hmonitor));
+    TRUE // continue enumeration
 }
 
 impl EventsLoop {
+    // TODO: Investigate opportunities for caching
     pub fn get_available_monitors(&self) -> VecDeque<MonitorId> {
+        let mut monitors: VecDeque<MonitorId> = VecDeque::new();
         unsafe {
-            let mut result: VecDeque<MonitorId> = VecDeque::new();
-            winuser::EnumDisplayMonitors(ptr::null_mut(), ptr::null_mut(), Some(monitor_enum_proc), &mut result as *mut _ as LPARAM);
-            result
+            winuser::EnumDisplayMonitors(
+                ptr::null_mut(),
+                ptr::null_mut(),
+                Some(monitor_enum_proc),
+                &mut monitors as *mut _ as LPARAM,
+            );
         }
+        monitors
     }
 
-    pub fn get_current_monitor(handle: HWND) -> MonitorId {
-        unsafe {
-            let mut monitor_info: winuser::MONITORINFOEXW = mem::zeroed();
-            monitor_info.cbSize = mem::size_of::<winuser::MONITORINFOEXW>() as DWORD;
-
-            let hmonitor = winuser::MonitorFromWindow(handle, winuser::MONITOR_DEFAULTTONEAREST);
-
-            winuser::GetMonitorInfoW(
-                hmonitor,
-                &mut monitor_info as *mut winuser::MONITORINFOEXW as *mut winuser::MONITORINFO,
-            );
-
-            let place = monitor_info.rcMonitor;
-            let position = (place.left as i32, place.top as i32);
-            let dimensions = (
-                (place.right - place.left) as u32,
-                (place.bottom - place.top) as u32,
-            );
-
-            MonitorId {
-                adapter_name: monitor_info.szDevice,
-                hmonitor: super::monitor::HMonitor(hmonitor),
-                monitor_name: util::wchar_to_string(&monitor_info.szDevice),
-                primary: monitor_info.dwFlags & winuser::MONITORINFOF_PRIMARY != 0,
-                position,
-                dimensions,
-                hidpi_factor: 1.0,
-            }
-        }
+    pub fn get_current_monitor(hwnd: HWND) -> MonitorId {
+        let hmonitor = unsafe {
+            winuser::MonitorFromWindow(hwnd, winuser::MONITOR_DEFAULTTONEAREST)
+        };
+        MonitorId::from_hmonitor(hmonitor)
     }
 
     pub fn get_primary_monitor(&self) -> MonitorId {
-        // we simply get all available monitors and return the one with the `MONITORINFOF_PRIMARY` flag
-        // TODO: it is possible to query the win32 API for the primary monitor, this should be done
-        //  instead
-        for monitor in self.get_available_monitors().into_iter() {
-            if monitor.primary {
-                return monitor;
-            }
-        }
+        const ORIGIN: POINT = POINT { x: 0, y: 0 };
+        let hmonitor = unsafe {
+            winuser::MonitorFromPoint(ORIGIN, winuser::MONITOR_DEFAULTTOPRIMARY)
+        };
+        MonitorId::from_hmonitor(hmonitor)
+    }
+}
 
-        panic!("Failed to find the primary monitor")
+fn get_monitor_info(hmonitor: HMONITOR) -> Result<winuser::MONITORINFOEXW, util::WinError> {
+    let mut monitor_info: winuser::MONITORINFOEXW = unsafe { mem::uninitialized() };
+    monitor_info.cbSize = mem::size_of::<winuser::MONITORINFOEXW>() as DWORD;
+    let status = unsafe {
+        winuser::GetMonitorInfoW(
+            hmonitor,
+            &mut monitor_info as *mut winuser::MONITORINFOEXW as *mut winuser::MONITORINFO,
+        )
+    };
+    if status == 0 {
+        Err(util::WinError::from_last_error())
+    } else {
+        Ok(monitor_info)
     }
 }
 
 impl MonitorId {
-    /// See the docs if the crate root file.
+    pub(crate) fn from_hmonitor(hmonitor: HMONITOR) -> Self {
+        let monitor_info = get_monitor_info(hmonitor).expect("`GetMonitorInfoW` failed");
+        let place = monitor_info.rcMonitor;
+        let dimensions = (
+            (place.right - place.left) as u32,
+            (place.bottom - place.top) as u32,
+        );
+        MonitorId {
+            hmonitor: HMonitor(hmonitor),
+            monitor_name: util::wchar_ptr_to_string(monitor_info.szDevice.as_ptr()),
+            primary: util::has_flag(monitor_info.dwFlags, winuser::MONITORINFOF_PRIMARY),
+            position: (place.left as i32, place.top as i32),
+            dimensions,
+            hidpi_factor: dpi_to_scale_factor(get_monitor_dpi(hmonitor).unwrap_or(96)),
+        }
+    }
+
     #[inline]
     pub fn get_name(&self) -> Option<String> {
         Some(self.monitor_name.clone())
     }
 
-    /// See the docs of the crate root file.
     #[inline]
     pub fn get_native_identifier(&self) -> String {
         self.monitor_name.clone()
     }
 
-    /// See the docs of the crate root file.
     #[inline]
     pub fn get_hmonitor(&self) -> HMONITOR {
         self.hmonitor.0
     }
 
-    /// See the docs of the crate root file.
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
-        // TODO: retrieve the dimensions every time this is called
-        self.dimensions
-    }
-
-    /// A window that is positioned at these coordinates will overlap the monitor.
-    #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
-        self.position
+    pub fn get_dimensions(&self) -> PhysicalSize {
+        self.dimensions.into()
     }
 
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_position(&self) -> PhysicalPosition {
+        self.position.into()
+    }
+
+    #[inline]
+    pub fn get_hidpi_factor(&self) -> f64 {
         self.hidpi_factor
     }
 }

src/platform/windows/util.rs

@@ -1,9 +1,9 @@
-use std::{self, mem, ptr};
+use std::{self, mem, ptr, slice};
 use std::ops::BitAnd;
 
 use winapi::ctypes::wchar_t;
 use winapi::shared::minwindef::DWORD;
-use winapi::shared::windef::RECT;
+use winapi::shared::windef::{HWND, RECT};
 use winapi::um::errhandlingapi::GetLastError;
 use winapi::um::winbase::{
     FormatMessageW,
@@ -19,6 +19,7 @@ use winapi::um::winnt::{
     LANG_NEUTRAL,
     SUBLANG_DEFAULT,
 };
+use winapi::um::winuser;
 
 pub fn has_flag<T>(bitset: T, flag: T) -> bool
 where T:
@@ -28,9 +29,22 @@ where T:
 }
 
 pub fn wchar_to_string(wchar: &[wchar_t]) -> String {
-    String::from_utf16_lossy(wchar)
-        .trim_right_matches(0 as char)
-        .to_string()
+    String::from_utf16_lossy(wchar).to_string()
+}
+
+pub fn wchar_ptr_to_string(wchar: *const wchar_t) -> String {
+    let len = unsafe { lstrlenW(wchar) } as usize;
+    let wchar_slice = unsafe { slice::from_raw_parts(wchar, len) };
+    wchar_to_string(wchar_slice)
+}
+
+pub fn get_window_rect(hwnd: HWND) -> Option<RECT> {
+    let mut rect: RECT = unsafe { mem::uninitialized() };
+    if unsafe { winuser::GetWindowRect(hwnd, &mut rect) } != 0 {
+        Some(rect)
+    } else {
+        None
+    }
 }
 
 // This won't be needed anymore if we just add a derive to winapi.

src/platform/windows/window.rs

@@ -1,29 +1,34 @@
 #![cfg(target_os = "windows")]
 
-use std::cell::Cell;
+use std::cell::{Cell, RefCell};
 use std::ffi::OsStr;
 use std::{io, mem, ptr};
-use std::os::raw;
 use std::os::windows::ffi::OsStrExt;
 use std::sync::{Arc, Mutex};
 use std::sync::mpsc::channel;
 
-use winapi::shared::minwindef::{BOOL, DWORD, FALSE, TRUE, UINT};
+use winapi::ctypes::c_int;
+use winapi::shared::minwindef::{BOOL, DWORD, FALSE, LPARAM, TRUE, UINT, WORD, WPARAM};
 use winapi::shared::windef::{HDC, HWND, LPPOINT, POINT, RECT};
 use winapi::um::{combaseapi, dwmapi, libloaderapi, winuser};
 use winapi::um::objbase::{COINIT_MULTITHREADED};
 use winapi::um::shobjidl_core::{CLSID_TaskbarList, ITaskbarList2};
 use winapi::um::winnt::{LONG, LPCWSTR};
 
-use CreationError;
-use CursorState;
-use Icon;
-use MonitorId as RootMonitorId;
-use MouseCursor;
-use WindowAttributes;
-
+use {
+    CreationError,
+    CursorState,
+    Icon,
+    LogicalPosition,
+    LogicalSize,
+    MonitorId as RootMonitorId,
+    MouseCursor,
+    PhysicalSize,
+    WindowAttributes,
+};
 use platform::platform::{Cursor, EventsLoop, PlatformSpecificWindowBuilderAttributes, WindowId};
-use platform::platform::events_loop::{self, DESTROY_MSG_ID};
+use platform::platform::dpi::{BASE_DPI, dpi_to_scale_factor, get_window_dpi, get_window_scale_factor};
+use platform::platform::events_loop::{self, DESTROY_MSG_ID, INITIAL_DPI_MSG_ID};
 use platform::platform::icon::{self, IconType, WinIcon};
 use platform::platform::raw_input::register_all_mice_and_keyboards_for_raw_input;
 use platform::platform::util;
@@ -33,6 +38,12 @@ pub struct Window {
     /// Main handle for the window.
     window: WindowWrapper,
 
+    decorations: Cell<bool>,
+    maximized: Cell<bool>,
+    resizable: Cell<bool>,
+    fullscreen: RefCell<Option<::MonitorId>>,
+    always_on_top: Cell<bool>,
+
     /// The current window state.
     window_state: Arc<Mutex<events_loop::WindowState>>,
 
@@ -56,19 +67,16 @@ unsafe impl Sync for Window {}
 // and it added fifty pixels to the top.
 // From this we can perform the reverse calculation: Instead of expanding the rectangle, we shrink it.
 unsafe fn unjust_window_rect(prc: &mut RECT, style: DWORD, ex_style: DWORD) -> BOOL {
-    let mut rc: RECT = mem::zeroed();
-
+    let mut rc: RECT = mem::uninitialized();
     winuser::SetRectEmpty(&mut rc);
-
-    let frc = winuser::AdjustWindowRectEx(&mut rc, style, 0, ex_style);
-    if frc != 0 {
+    let status = winuser::AdjustWindowRectEx(&mut rc, style, 0, ex_style);
+    if status != 0 {
         prc.left -= rc.left;
         prc.top -= rc.top;
         prc.right -= rc.right;
         prc.bottom -= rc.bottom;
     }
-
-    frc
+    status
 }
 
 impl Window {
@@ -78,16 +86,13 @@ impl Window {
         pl_attr: PlatformSpecificWindowBuilderAttributes,
     ) -> Result<Window, CreationError> {
         let (tx, rx) = channel();
-
         let proxy = events_loop.create_proxy();
-
         events_loop.execute_in_thread(move |inserter| {
             // We dispatch an `init` function because of code style.
             // First person to remove the need for cloning here gets a cookie!
             let win = unsafe { init(w_attr.clone(), pl_attr.clone(), inserter, proxy.clone()) };
             let _ = tx.send(win);
         });
-
         rx.recv().unwrap()
     }
 
@@ -115,168 +120,193 @@ impl Window {
         }
     }
 
-    /// See the docs in the crate root file.
-    pub fn get_position(&self) -> Option<(i32, i32)> {
-        let mut rect: RECT = unsafe { mem::uninitialized() };
-
-        if unsafe { winuser::GetWindowRect(self.window.0, &mut rect) } != 0 {
-            Some((rect.left as i32, rect.top as i32))
-        } else {
-            None
-        }
+    pub(crate) fn get_position_physical(&self) -> Option<(i32, i32)> {
+        util::get_window_rect(self.window.0)
+            .map(|rect| (rect.left as i32, rect.top as i32))
     }
 
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
-        use std::mem;
+    #[inline]
+    pub fn get_position(&self) -> Option<LogicalPosition> {
+        self.get_position_physical()
+            .map(|physical_position| {
+                let dpi_factor = self.get_hidpi_factor();
+                LogicalPosition::from_physical(physical_position, dpi_factor)
+            })
+    }
 
+    pub(crate) fn get_inner_position_physical(&self) -> Option<(i32, i32)> {
         let mut position: POINT = unsafe { mem::zeroed() };
         if unsafe { winuser::ClientToScreen(self.window.0, &mut position) } == 0 {
             return None;
         }
-
         Some((position.x, position.y))
     }
 
-    /// See the docs in the crate root file.
-    pub fn set_position(&self, x: i32, y: i32) {
+    #[inline]
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
+        self.get_inner_position_physical()
+            .map(|physical_position| {
+                let dpi_factor = self.get_hidpi_factor();
+                LogicalPosition::from_physical(physical_position, dpi_factor)
+            })
+    }
+
+    pub(crate) fn set_position_physical(&self, x: i32, y: i32) {
         unsafe {
-            winuser::SetWindowPos(self.window.0, ptr::null_mut(), x as raw::c_int, y as raw::c_int,
-                                 0, 0, winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOSIZE);
+            winuser::SetWindowPos(
+                self.window.0,
+                ptr::null_mut(),
+                x as c_int,
+                y as c_int,
+                0,
+                0,
+                winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOSIZE,
+            );
             winuser::UpdateWindow(self.window.0);
         }
     }
 
-    /// See the docs in the crate root file.
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
-        let mut rect: RECT = unsafe { mem::uninitialized() };
+    pub fn set_position(&self, logical_position: LogicalPosition) {
+        let dpi_factor = self.get_hidpi_factor();
+        let (x, y) = logical_position.to_physical(dpi_factor).into();
+        self.set_position_physical(x, y);
+    }
 
+    pub(crate) fn get_inner_size_physical(&self) -> Option<(u32, u32)> {
+        let mut rect: RECT = unsafe { mem::uninitialized() };
         if unsafe { winuser::GetClientRect(self.window.0, &mut rect) } == 0 {
-            return None
+            return None;
         }
-
         Some((
             (rect.right - rect.left) as u32,
-            (rect.bottom - rect.top) as u32
+            (rect.bottom - rect.top) as u32,
         ))
     }
 
-    /// See the docs in the crate root file.
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
-        let mut rect: RECT = unsafe { mem::uninitialized() };
-
-        if unsafe { winuser::GetWindowRect(self.window.0, &mut rect) } == 0 {
-            return None
-        }
-
-        Some((
-            (rect.right - rect.left) as u32,
-            (rect.bottom - rect.top) as u32
-        ))
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
+        self.get_inner_size_physical()
+            .map(|physical_size| {
+                let dpi_factor = self.get_hidpi_factor();
+                LogicalSize::from_physical(physical_size, dpi_factor)
+            })
     }
 
-    /// See the docs in the crate root file.
-    pub fn set_inner_size(&self, x: u32, y: u32) {
+    pub(crate) fn get_outer_size_physical(&self) -> Option<(u32, u32)> {
+        util::get_window_rect(self.window.0)
+            .map(|rect| (
+                (rect.right - rect.left) as u32,
+                (rect.bottom - rect.top) as u32,
+            ))
+    }
+
+    #[inline]
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
+        self.get_outer_size_physical()
+            .map(|physical_size| {
+                let dpi_factor = self.get_hidpi_factor();
+                LogicalSize::from_physical(physical_size, dpi_factor)
+            })
+    }
+
+    pub(crate) fn set_inner_size_physical(&self, x: u32, y: u32) {
         unsafe {
-            // Calculate the outer size based upon the specified inner size
-            let mut rect = RECT { top: 0, left: 0, bottom: y as LONG, right: x as LONG };
+            let mut rect = RECT {
+                top: 0,
+                left: 0,
+                bottom: y as LONG,
+                right: x as LONG,
+            };
             let dw_style = winuser::GetWindowLongA(self.window.0, winuser::GWL_STYLE) as DWORD;
             let b_menu = !winuser::GetMenu(self.window.0).is_null() as BOOL;
             let dw_style_ex = winuser::GetWindowLongA(self.window.0, winuser::GWL_EXSTYLE) as DWORD;
             winuser::AdjustWindowRectEx(&mut rect, dw_style, b_menu, dw_style_ex);
-            let outer_x = (rect.right - rect.left).abs() as raw::c_int;
-            let outer_y = (rect.top - rect.bottom).abs() as raw::c_int;
-
-            winuser::SetWindowPos(self.window.0, ptr::null_mut(), 0, 0, outer_x, outer_y,
-                winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOREPOSITION | winuser::SWP_NOMOVE);
+            let outer_x = (rect.right - rect.left).abs() as c_int;
+            let outer_y = (rect.top - rect.bottom).abs() as c_int;
+            winuser::SetWindowPos(
+                self.window.0,
+                ptr::null_mut(),
+                0,
+                0,
+                outer_x,
+                outer_y,
+                winuser::SWP_ASYNCWINDOWPOS
+                | winuser::SWP_NOZORDER
+                | winuser::SWP_NOREPOSITION
+                | winuser::SWP_NOMOVE,
+            );
             winuser::UpdateWindow(self.window.0);
         }
     }
 
-    /// See the docs in the crate root file.
     #[inline]
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        let mut window_state = self.window_state.lock().unwrap();
-        window_state.attributes.min_dimensions = dimensions;
-
-        // Make windows re-check the window size bounds.
-        if let Some(inner_size) = self.get_inner_size() {
-            unsafe {
-                let mut rect = RECT { top: 0, left: 0, bottom: inner_size.1 as LONG, right: inner_size.0 as LONG };
-                let dw_style = winuser::GetWindowLongA(self.window.0, winuser::GWL_STYLE) as DWORD;
-                let b_menu = !winuser::GetMenu(self.window.0).is_null() as BOOL;
-                let dw_style_ex = winuser::GetWindowLongA(self.window.0, winuser::GWL_EXSTYLE) as DWORD;
-                winuser::AdjustWindowRectEx(&mut rect, dw_style, b_menu, dw_style_ex);
-                let outer_x = (rect.right - rect.left).abs() as raw::c_int;
-                let outer_y = (rect.top - rect.bottom).abs() as raw::c_int;
-
-                winuser::SetWindowPos(self.window.0, ptr::null_mut(), 0, 0, outer_x, outer_y,
-                    winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOREPOSITION | winuser::SWP_NOMOVE);
-            }
-        }
+    pub fn set_inner_size(&self, logical_size: LogicalSize) {
+        let dpi_factor = self.get_hidpi_factor();
+        let (width, height) = logical_size.to_physical(dpi_factor).into();
+        self.set_inner_size_physical(width, height);
     }
 
-    /// See the docs in the crate root file.
-    #[inline]
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
-        let mut window_state = self.window_state.lock().unwrap();
-        window_state.attributes.max_dimensions = dimensions;
-
+    pub(crate) fn set_min_dimensions_physical(&self, dimensions: Option<(u32, u32)>) {
+        self.window_state.lock().unwrap().min_size = dimensions.map(Into::into);
         // Make windows re-check the window size bounds.
-        if let Some(inner_size) = self.get_inner_size() {
-            unsafe {
-                let mut rect = RECT { top: 0, left: 0, bottom: inner_size.1 as LONG, right: inner_size.0 as LONG };
-                let dw_style = winuser::GetWindowLongA(self.window.0, winuser::GWL_STYLE) as DWORD;
-                let b_menu = !winuser::GetMenu(self.window.0).is_null() as BOOL;
-                let dw_style_ex = winuser::GetWindowLongA(self.window.0, winuser::GWL_EXSTYLE) as DWORD;
-                winuser::AdjustWindowRectEx(&mut rect, dw_style, b_menu, dw_style_ex);
-                let outer_x = (rect.right - rect.left).abs() as raw::c_int;
-                let outer_y = (rect.top - rect.bottom).abs() as raw::c_int;
+        self.get_inner_size_physical()
+            .map(|(width, height)| self.set_inner_size_physical(width, height));
+    }
 
-                winuser::SetWindowPos(self.window.0, ptr::null_mut(), 0, 0, outer_x, outer_y,
-                    winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOREPOSITION | winuser::SWP_NOMOVE);
-            }
-        }
+    #[inline]
+    pub fn set_min_dimensions(&self, logical_size: Option<LogicalSize>) {
+        let physical_size = logical_size.map(|logical_size| {
+            let dpi_factor = self.get_hidpi_factor();
+            logical_size.to_physical(dpi_factor).into()
+        });
+        self.set_min_dimensions_physical(physical_size);
+    }
+
+    pub fn set_max_dimensions_physical(&self, dimensions: Option<(u32, u32)>) {
+        self.window_state.lock().unwrap().max_size = dimensions.map(Into::into);
+        // Make windows re-check the window size bounds.
+        self.get_inner_size_physical()
+            .map(|(width, height)| self.set_inner_size_physical(width, height));
+    }
+
+    #[inline]
+    pub fn set_max_dimensions(&self, logical_size: Option<LogicalSize>) {
+        let physical_size = logical_size.map(|logical_size| {
+            let dpi_factor = self.get_hidpi_factor();
+            logical_size.to_physical(dpi_factor).into()
+        });
+        self.set_max_dimensions_physical(physical_size);
     }
 
     #[inline]
     pub fn set_resizable(&self, resizable: bool) {
-        if let Ok(mut window_state) = self.window_state.lock() {
-            if window_state.attributes.resizable == resizable {
-                return;
-            }
-            if window_state.attributes.fullscreen.is_some() {
-                window_state.attributes.resizable = resizable;
-                return;
-            }
-            let window = self.window.clone();
-            let mut style = unsafe {
-                winuser::GetWindowLongW(self.window.0, winuser::GWL_STYLE)
-            };
-            if resizable {
-                style |= winuser::WS_SIZEBOX as LONG;
-            } else {
-                style &= !winuser::WS_SIZEBOX as LONG;
-            }
-            unsafe {
-                winuser::SetWindowLongW(
-                    window.0,
-                    winuser::GWL_STYLE,
-                    style as _,
-                );
-            };
-            window_state.attributes.resizable = resizable;
+        if resizable == self.resizable.get() {
+            return;
+        }
+        if self.fullscreen.borrow().is_some() {
+            // If we're in fullscreen, update stored configuration but don't apply anything.
+            self.resizable.replace(resizable);
+            return;
         }
-    }
 
-    // TODO: remove
-    pub fn platform_display(&self) -> *mut ::libc::c_void {
-        panic!()        // Deprecated function ; we don't care anymore
-    }
-    // TODO: remove
-    pub fn platform_window(&self) -> *mut ::libc::c_void {
-        self.window.0 as *mut ::libc::c_void
+        let mut style = unsafe {
+            winuser::GetWindowLongW(self.window.0, winuser::GWL_STYLE)
+        };
+        if resizable {
+            style |= winuser::WS_SIZEBOX as LONG;
+        } else {
+            style &= !winuser::WS_SIZEBOX as LONG;
+        }
+
+        unsafe {
+            winuser::SetWindowLongW(
+                self.window.0,
+                winuser::GWL_STYLE,
+                style as _,
+            );
+        };
+        self.resizable.replace(resizable);
     }
 
     /// Returns the `hwnd` of this window.
@@ -411,29 +441,30 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
-        1.0
+    pub fn get_hidpi_factor(&self) -> f64 {
+        get_window_scale_factor(self.window.0, self.window.1)
     }
 
-    pub fn set_cursor_position(&self, x: i32, y: i32) -> Result<(), ()> {
-        let mut point = POINT {
-            x: x,
-            y: y,
-        };
-
+    fn set_cursor_position_physical(&self, x: i32, y: i32) -> Result<(), ()> {
+        let mut point = POINT { x, y };
         unsafe {
             if winuser::ClientToScreen(self.window.0, &mut point) == 0 {
                 return Err(());
             }
-
             if winuser::SetCursorPos(point.x, point.y) == 0 {
                 return Err(());
             }
         }
-
         Ok(())
     }
 
+    #[inline]
+    pub fn set_cursor_position(&self, logical_position: LogicalPosition) -> Result<(), ()> {
+        let dpi_factor = self.get_hidpi_factor();
+        let (x, y) = logical_position.to_physical(dpi_factor).into();
+        self.set_cursor_position_physical(x, y)
+    }
+
     #[inline]
     pub fn id(&self) -> WindowId {
         WindowId(self.window.0)
@@ -441,18 +472,13 @@ impl Window {
 
     #[inline]
     pub fn set_maximized(&self, maximized: bool) {
-        let mut window_state = self.window_state.lock().unwrap();
-
-        window_state.attributes.maximized = maximized;
-        // we only maximized if we are not in fullscreen
-        if window_state.attributes.fullscreen.is_some() {
-            return;
-        }
+        self.maximized.replace(maximized);
+        // We only maximize if we're not in fullscreen.
+        if self.fullscreen.borrow().is_some() { return; }
 
         let window = self.window.clone();
         unsafe {
-            // And because ShowWindow will resize the window
-            // We call it in the main thread
+            // `ShowWindow` resizes the window, so it must be called from the main thread.
             self.events_loop_proxy.execute_in_thread(move |_| {
                 winuser::ShowWindow(
                     window.0,
@@ -469,15 +495,15 @@ impl Window {
     unsafe fn set_fullscreen_style(&self) -> (LONG, LONG) {
         let mut window_state = self.window_state.lock().unwrap();
 
-        if window_state.attributes.fullscreen.is_none() || window_state.saved_window_info.is_none() {
-            let mut rect: RECT = mem::zeroed();
-
-            winuser::GetWindowRect(self.window.0, &mut rect);
-
+        if self.fullscreen.borrow().is_none() || window_state.saved_window_info.is_none() {
+            let rect = util::get_window_rect(self.window.0).expect("`GetWindowRect` failed");
+            let dpi_factor = Some(self.get_hidpi_factor());
             window_state.saved_window_info = Some(events_loop::SavedWindowInfo {
                 style: winuser::GetWindowLongW(self.window.0, winuser::GWL_STYLE),
                 ex_style: winuser::GetWindowLongW(self.window.0, winuser::GWL_EXSTYLE),
                 rect,
+                is_fullscreen: true,
+                dpi_factor,
             });
         }
 
@@ -485,15 +511,14 @@ impl Window {
         let mut placement: winuser::WINDOWPLACEMENT = mem::zeroed();
         placement.length = mem::size_of::<winuser::WINDOWPLACEMENT>() as u32;
         winuser::GetWindowPlacement(self.window.0, &mut placement);
-        window_state.attributes.maximized =
-            placement.showCmd == (winuser::SW_SHOWMAXIMIZED as u32);
+        self.maximized.replace(placement.showCmd == (winuser::SW_SHOWMAXIMIZED as u32));
         let saved_window_info = window_state.saved_window_info.as_ref().unwrap();
 
         (saved_window_info.style, saved_window_info.ex_style)
     }
 
     unsafe fn restore_saved_window(&self) {
-        let window_state = self.window_state.lock().unwrap();
+        let mut window_state = self.window_state.lock().unwrap();
 
         // 'saved_window_info' can be None if the window has never been
         // in fullscreen mode before this method gets called.
@@ -504,18 +529,21 @@ impl Window {
         // Reset original window style and size.  The multiple window size/moves
         // here are ugly, but if SetWindowPos() doesn't redraw, the taskbar won't be
         // repainted.  Better-looking methods welcome.
+        {
+            let saved_window_info = window_state.saved_window_info.as_mut().unwrap();
+            saved_window_info.is_fullscreen = false;
+        }
         let saved_window_info = window_state.saved_window_info.as_ref().unwrap();
 
         let rect = saved_window_info.rect.clone();
         let window = self.window.clone();
         let (mut style, ex_style) = (saved_window_info.style, saved_window_info.ex_style);
 
-        let maximized = window_state.attributes.maximized;
-        let resizable = window_state.attributes.resizable;
+        let maximized = self.maximized.get();
+        let resizable = self.resizable.get();
 
-        // On restore, resize to the previous saved rect size.
-        // And because SetWindowPos will resize the window
-        // We call it in the main thread
+        // We're restoring the window to its size and position from before being fullscreened.
+        // `ShowWindow` resizes the window, so it must be called from the main thread.
         self.events_loop_proxy.execute_in_thread(move |_| {
             if resizable {
                 style |= winuser::WS_SIZEBOX as LONG;
@@ -532,11 +560,13 @@ impl Window {
                 rect.top,
                 rect.right - rect.left,
                 rect.bottom - rect.top,
-                winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER | winuser::SWP_NOACTIVATE
-                    | winuser::SWP_FRAMECHANGED,
+                winuser::SWP_ASYNCWINDOWPOS
+                | winuser::SWP_NOZORDER
+                | winuser::SWP_NOACTIVATE
+                | winuser::SWP_FRAMECHANGED,
             );
 
-            // if it was set to maximized when it were fullscreened, we restore it as well
+            // We apply any requested changes to maximization state that occurred while we were in fullscreen.
             winuser::ShowWindow(
                 window.0,
                 if maximized {
@@ -555,8 +585,8 @@ impl Window {
         unsafe {
             match &monitor {
                 &Some(RootMonitorId { ref inner }) => {
-                    let pos = inner.get_position();
-                    let dim = inner.get_dimensions();
+                    let (x, y): (i32, i32) = inner.get_position().into();
+                    let (width, height): (u32, u32) = inner.get_dimensions().into();
                     let window = self.window.clone();
 
                     let (style, ex_style) = self.set_fullscreen_style();
@@ -582,10 +612,10 @@ impl Window {
                         winuser::SetWindowPos(
                             window.0,
                             ptr::null_mut(),
-                            pos.0,
-                            pos.1,
-                            dim.0 as i32,
-                            dim.1 as i32,
+                            x as c_int,
+                            y as c_int,
+                            width as c_int,
+                            height as c_int,
                             winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER
                                 | winuser::SWP_NOACTIVATE
                                 | winuser::SWP_FRAMECHANGED,
@@ -600,122 +630,119 @@ impl Window {
             }
         }
 
-        let mut window_state = self.window_state.lock().unwrap();
-        window_state.attributes.fullscreen = monitor;
+        self.fullscreen.replace(monitor);
     }
 
     #[inline]
     pub fn set_decorations(&self, decorations: bool) {
-        if let Ok(mut window_state) = self.window_state.lock() {
-            if window_state.attributes.decorations == decorations {
-                return;
-            }
+        if self.decorations.get() == decorations {
+            return;
+        }
 
-            let style_flags = (winuser::WS_CAPTION | winuser::WS_THICKFRAME) as LONG;
-            let ex_style_flags = (winuser::WS_EX_WINDOWEDGE) as LONG;
+        let style_flags = (winuser::WS_CAPTION | winuser::WS_THICKFRAME) as LONG;
+        let ex_style_flags = (winuser::WS_EX_WINDOWEDGE) as LONG;
 
-            // if we are in fullscreen mode, we only change the saved window info
-            if window_state.attributes.fullscreen.is_some() {
-                {
-                    let mut saved = window_state.saved_window_info.as_mut().unwrap();
+        // if we are in fullscreen mode, we only change the saved window info
+        if self.fullscreen.borrow().is_some() {
+            {
+                let mut window_state = self.window_state.lock().unwrap();
+                let saved = window_state.saved_window_info.as_mut().unwrap();
 
-                    unsafe {
-                        unjust_window_rect(&mut saved.rect, saved.style as _, saved.ex_style as _);
-                    }
-
-                    if decorations {
-                        saved.style = saved.style | style_flags;
-                        saved.ex_style = saved.ex_style | ex_style_flags;
-                    } else {
-                        saved.style = saved.style & !style_flags;
-                        saved.ex_style = saved.ex_style & !ex_style_flags;
-                    }
-
-                    unsafe {
-                        winuser::AdjustWindowRectEx(
-                            &mut saved.rect,
-                            saved.style as _,
-                            0,
-                            saved.ex_style as _,
-                        );
-                    }
+                unsafe {
+                    unjust_window_rect(&mut saved.rect, saved.style as _, saved.ex_style as _);
                 }
 
-                window_state.attributes.decorations = decorations;
-                return;
-            }
-
-            unsafe {
-                let mut rect: RECT = mem::zeroed();
-                winuser::GetWindowRect(self.window.0, &mut rect);
-
-                let mut style = winuser::GetWindowLongW(self.window.0, winuser::GWL_STYLE);
-                let mut ex_style = winuser::GetWindowLongW(self.window.0, winuser::GWL_EXSTYLE);
-                unjust_window_rect(&mut rect, style as _, ex_style as _);
-
                 if decorations {
-                    style = style | style_flags;
-                    ex_style = ex_style | ex_style_flags;
+                    saved.style = saved.style | style_flags;
+                    saved.ex_style = saved.ex_style | ex_style_flags;
                 } else {
-                    style = style & !style_flags;
-                    ex_style = ex_style & !ex_style_flags;
+                    saved.style = saved.style & !style_flags;
+                    saved.ex_style = saved.ex_style & !ex_style_flags;
                 }
 
-                let window = self.window.clone();
-
-                self.events_loop_proxy.execute_in_thread(move |_| {
-                    winuser::SetWindowLongW(window.0, winuser::GWL_STYLE, style);
-                    winuser::SetWindowLongW(window.0, winuser::GWL_EXSTYLE, ex_style);
-                    winuser::AdjustWindowRectEx(&mut rect, style as _, 0, ex_style as _);
-
-                    winuser::SetWindowPos(
-                        window.0,
-                        ptr::null_mut(),
-                        rect.left,
-                        rect.top,
-                        rect.right - rect.left,
-                        rect.bottom - rect.top,
-                        winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER
-                            | winuser::SWP_NOACTIVATE
-                            | winuser::SWP_FRAMECHANGED,
+                unsafe {
+                    winuser::AdjustWindowRectEx(
+                        &mut saved.rect,
+                        saved.style as _,
+                        0,
+                        saved.ex_style as _,
                     );
-                });
+                }
             }
 
-            window_state.attributes.decorations = decorations;
+            self.decorations.replace(decorations);
+            return;
         }
+
+        unsafe {
+            let mut rect: RECT = mem::zeroed();
+            winuser::GetWindowRect(self.window.0, &mut rect);
+
+            let mut style = winuser::GetWindowLongW(self.window.0, winuser::GWL_STYLE);
+            let mut ex_style = winuser::GetWindowLongW(self.window.0, winuser::GWL_EXSTYLE);
+            unjust_window_rect(&mut rect, style as _, ex_style as _);
+
+            if decorations {
+                style = style | style_flags;
+                ex_style = ex_style | ex_style_flags;
+            } else {
+                style = style & !style_flags;
+                ex_style = ex_style & !ex_style_flags;
+            }
+
+            let window = self.window.clone();
+
+            self.events_loop_proxy.execute_in_thread(move |_| {
+                winuser::SetWindowLongW(window.0, winuser::GWL_STYLE, style);
+                winuser::SetWindowLongW(window.0, winuser::GWL_EXSTYLE, ex_style);
+                winuser::AdjustWindowRectEx(&mut rect, style as _, 0, ex_style as _);
+
+                winuser::SetWindowPos(
+                    window.0,
+                    ptr::null_mut(),
+                    rect.left,
+                    rect.top,
+                    rect.right - rect.left,
+                    rect.bottom - rect.top,
+                    winuser::SWP_ASYNCWINDOWPOS
+                    | winuser::SWP_NOZORDER
+                    | winuser::SWP_NOACTIVATE
+                    | winuser::SWP_FRAMECHANGED,
+                );
+            });
+        }
+
+        self.decorations.replace(decorations);
     }
 
     #[inline]
     pub fn set_always_on_top(&self, always_on_top: bool) {
-        if let Ok(mut window_state) = self.window_state.lock() {
-            if window_state.attributes.always_on_top == always_on_top {
-                return;
-            }
-
-            let window = self.window.clone();
-            self.events_loop_proxy.execute_in_thread(move |_| {
-                let insert_after = if always_on_top {
-                    winuser::HWND_TOPMOST
-                } else {
-                    winuser::HWND_NOTOPMOST
-                };
-                unsafe {
-                    winuser::SetWindowPos(
-                        window.0,
-                        insert_after,
-                        0,
-                        0,
-                        0,
-                        0,
-                        winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOMOVE | winuser::SWP_NOSIZE,
-                    );
-                    winuser::UpdateWindow(window.0);
-                }
-            });
-
-            window_state.attributes.always_on_top = always_on_top;
+        if self.always_on_top.get() == always_on_top {
+            return;
         }
+
+        let window = self.window.clone();
+        self.events_loop_proxy.execute_in_thread(move |_| {
+            let insert_after = if always_on_top {
+                winuser::HWND_TOPMOST
+            } else {
+                winuser::HWND_NOTOPMOST
+            };
+            unsafe {
+                winuser::SetWindowPos(
+                    window.0,
+                    insert_after,
+                    0,
+                    0,
+                    0,
+                    0,
+                    winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOMOVE | winuser::SWP_NOSIZE,
+                );
+                winuser::UpdateWindow(window.0);
+            }
+        });
+
+        self.always_on_top.replace(always_on_top);
     }
 
     #[inline]
@@ -752,7 +779,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+    pub fn set_ime_spot(&self, _logical_spot: LogicalPosition) {
         unimplemented!();
     }
 }
@@ -779,27 +806,26 @@ pub struct WindowWrapper(HWND, HDC);
 // https://github.com/retep998/winapi-rs/issues/396
 unsafe impl Send for WindowWrapper {}
 
-pub unsafe fn adjust_size(
-    (x, y): (u32, u32), style: DWORD, ex_style: DWORD,
-) -> (LONG, LONG) {
-    let mut rect = RECT { left: 0, right: x as LONG, top: 0, bottom: y as LONG };
+pub unsafe fn adjust_size(physical_size: PhysicalSize, style: DWORD, ex_style: DWORD) -> (LONG, LONG) {
+    let (width, height): (u32, u32) = physical_size.into();
+    let mut rect = RECT { left: 0, right: width as LONG, top: 0, bottom: height as LONG };
     winuser::AdjustWindowRectEx(&mut rect, style, 0, ex_style);
     (rect.right - rect.left, rect.bottom - rect.top)
 }
 
 unsafe fn init(
-    mut window: WindowAttributes,
+    mut attributes: WindowAttributes,
     mut pl_attribs: PlatformSpecificWindowBuilderAttributes,
     inserter: events_loop::Inserter,
     events_loop_proxy: events_loop::EventsLoopProxy,
 ) -> Result<Window, CreationError> {
-    let title = OsStr::new(&window.title)
+    let title = OsStr::new(&attributes.title)
         .encode_wide()
         .chain(Some(0).into_iter())
         .collect::<Vec<_>>();
 
     let window_icon = {
-        let icon = window.window_icon
+        let icon = attributes.window_icon
             .take()
             .map(WinIcon::from_icon);
         if icon.is_some() {
@@ -826,14 +852,19 @@ unsafe fn init(
     // registering the window class
     let class_name = register_window_class(&window_icon, &taskbar_icon);
 
+    let (width, height) = attributes.dimensions
+        .map(Into::into)
+        .unwrap_or((1024, 768));
     // building a RECT object with coordinates
     let mut rect = RECT {
-        left: 0, right: window.dimensions.unwrap_or((1024, 768)).0 as LONG,
-        top: 0, bottom: window.dimensions.unwrap_or((1024, 768)).1 as LONG,
+        left: 0,
+        right: width as LONG,
+        top: 0,
+        bottom: height as LONG,
     };
 
     // computing the style and extended style of the window
-    let (mut ex_style, style) = if !window.decorations {
+    let (mut ex_style, style) = if !attributes.decorations {
         (winuser::WS_EX_APPWINDOW,
             //winapi::WS_POPUP is incompatible with winapi::WS_CHILD
             if pl_attribs.parent.is_some() {
@@ -848,7 +879,7 @@ unsafe fn init(
             winuser::WS_OVERLAPPEDWINDOW | winuser::WS_CLIPSIBLINGS | winuser::WS_CLIPCHILDREN)
     };
 
-    if window.always_on_top {
+    if attributes.always_on_top {
         ex_style |= winuser::WS_EX_TOPMOST;
     }
 
@@ -857,14 +888,15 @@ unsafe fn init(
 
     // creating the real window this time, by using the functions in `extra_functions`
     let real_window = {
-        let (width, height) = if window.dimensions.is_some() {
-            let min_dimensions = window.min_dimensions
-                .map(|d| adjust_size(d, style, ex_style))
+        let (adjusted_width, adjusted_height) = if attributes.dimensions.is_some() {
+            let min_dimensions = attributes.min_dimensions
+                .map(|logical_size| PhysicalSize::from_logical(logical_size, 1.0))
+                .map(|physical_size| adjust_size(physical_size, style, ex_style))
                 .unwrap_or((0, 0));
-            let max_dimensions = window.max_dimensions
-                .map(|d| adjust_size(d, style, ex_style))
-                .unwrap_or((raw::c_int::max_value(), raw::c_int::max_value()));
-
+            let max_dimensions = attributes.max_dimensions
+                .map(|logical_size| PhysicalSize::from_logical(logical_size, 1.0))
+                .map(|physical_size| adjust_size(physical_size, style, ex_style))
+                .unwrap_or((c_int::max_value(), c_int::max_value()));
             (
                 Some((rect.right - rect.left).min(max_dimensions.0).max(min_dimensions.0)),
                 Some((rect.bottom - rect.top).min(max_dimensions.1).max(min_dimensions.1))
@@ -873,13 +905,13 @@ unsafe fn init(
             (None, None)
         };
 
-        let mut style = if !window.visible {
+        let mut style = if !attributes.visible {
             style
         } else {
             style | winuser::WS_VISIBLE
         };
 
-        if !window.resizable {
+        if !attributes.resizable {
             style &= !winuser::WS_SIZEBOX;
         }
 
@@ -892,10 +924,13 @@ unsafe fn init(
             title.as_ptr() as LPCWSTR,
             style | winuser::WS_CLIPSIBLINGS | winuser::WS_CLIPCHILDREN,
             winuser::CW_USEDEFAULT, winuser::CW_USEDEFAULT,
-            width.unwrap_or(winuser::CW_USEDEFAULT), height.unwrap_or(winuser::CW_USEDEFAULT),
+            adjusted_width.unwrap_or(winuser::CW_USEDEFAULT),
+            adjusted_height.unwrap_or(winuser::CW_USEDEFAULT),
             pl_attribs.parent.unwrap_or(ptr::null_mut()),
-            ptr::null_mut(), libloaderapi::GetModuleHandleW(ptr::null()),
-            ptr::null_mut());
+            ptr::null_mut(),
+            libloaderapi::GetModuleHandleW(ptr::null()),
+            ptr::null_mut(),
+        );
 
         if handle.is_null() {
             return Err(CreationError::OsError(format!("CreateWindowEx function failed: {}",
@@ -922,21 +957,42 @@ unsafe fn init(
         }
     }
 
-    let (transparent, maximized, fullscreen) = (
-        window.transparent.clone(), window.maximized.clone(), window.fullscreen.clone()
-    );
+    let dpi = get_window_dpi(real_window.0, real_window.1);
+    let dpi_factor = dpi_to_scale_factor(dpi);
+    if dpi != BASE_DPI {
+        let mut packed_dimensions = 0;
+        // MAKELPARAM isn't provided by winapi yet.
+        let ptr = &mut packed_dimensions as *mut LPARAM as *mut WORD;
+        *ptr.offset(0) = width as WORD;
+        *ptr.offset(1) = height as WORD;
+        winuser::PostMessageW(
+            real_window.0,
+            *INITIAL_DPI_MSG_ID,
+            dpi as WPARAM,
+            packed_dimensions,
+        );
+    }
 
-    // Creating a mutex to track the current window state
-    let window_state = Arc::new(Mutex::new(events_loop::WindowState {
-        cursor: Cursor(winuser::IDC_ARROW), // use arrow by default
-        cursor_state: CursorState::Normal,
-        attributes: window,
-        mouse_in_window: false,
-        saved_window_info: None,
-    }));
+    let window_state = {
+        let max_size = attributes.max_dimensions
+            .map(|logical_size| PhysicalSize::from_logical(logical_size, dpi_factor));
+        let min_size = attributes.min_dimensions
+            .map(|logical_size| PhysicalSize::from_logical(logical_size, dpi_factor));
+        let mut window_state = events_loop::WindowState {
+            cursor: Cursor(winuser::IDC_ARROW), // use arrow by default
+            cursor_state: CursorState::Normal,
+            max_size,
+            min_size,
+            mouse_in_window: false,
+            saved_window_info: None,
+            dpi_factor,
+        };
+        // Creating a mutex to track the current window state
+        Arc::new(Mutex::new(window_state))
+    };
 
     // making the window transparent
-    if transparent {
+    if attributes.transparent {
         let bb = dwmapi::DWM_BLURBEHIND {
             dwFlags: 0x1, // FIXME: DWM_BB_ENABLE;
             fEnable: 1,
@@ -950,14 +1006,19 @@ unsafe fn init(
     let win = Window {
         window: real_window,
         window_state: window_state,
+        decorations: Cell::new(attributes.decorations),
+        maximized: Cell::new(attributes.maximized.clone()),
+        resizable: Cell::new(attributes.resizable.clone()),
+        fullscreen: RefCell::new(attributes.fullscreen.clone()),
+        always_on_top: Cell::new(attributes.always_on_top),
         window_icon: Cell::new(window_icon),
         taskbar_icon: Cell::new(taskbar_icon),
         events_loop_proxy,
     };
 
-    win.set_maximized(maximized);
-    if let Some(_) = fullscreen {
-        win.set_fullscreen(fullscreen);
+    win.set_maximized(attributes.maximized);
+    if let Some(_) = attributes.fullscreen {
+        win.set_fullscreen(attributes.fullscreen);
         force_window_active(win.window.0);
     }
 

src/window.rs

@@ -1,16 +1,20 @@
 use std::collections::vec_deque::IntoIter as VecDequeIter;
 
-use CreationError;
-use CursorState;
-use EventsLoop;
-use Icon;
-use MouseCursor;
-use Window;
-use WindowBuilder;
-use WindowId;
-
-use libc;
-use platform;
+use {
+    CreationError,
+    CursorState,
+    EventsLoop,
+    Icon,
+    LogicalPosition,
+    LogicalSize,
+    MouseCursor,
+    PhysicalPosition,
+    PhysicalSize,
+    platform,
+    Window,
+    WindowBuilder,
+    WindowId,
+};
 
 impl WindowBuilder {
     /// Initializes a new `WindowBuilder` with default values.
@@ -23,29 +27,23 @@ impl WindowBuilder {
     }
 
     /// Requests the window to be of specific dimensions.
-    ///
-    /// Width and height are in pixels.
     #[inline]
-    pub fn with_dimensions(mut self, width: u32, height: u32) -> WindowBuilder {
-        self.window.dimensions = Some((width, height));
+    pub fn with_dimensions(mut self, size: LogicalSize) -> WindowBuilder {
+        self.window.dimensions = Some(size);
         self
     }
 
     /// Sets a minimum dimension size for the window
-    ///
-    /// Width and height are in pixels.
     #[inline]
-    pub fn with_min_dimensions(mut self, width: u32, height: u32) -> WindowBuilder {
-        self.window.min_dimensions = Some((width, height));
+    pub fn with_min_dimensions(mut self, min_size: LogicalSize) -> WindowBuilder {
+        self.window.min_dimensions = Some(min_size);
         self
     }
 
     /// Sets a maximum dimension size for the window
-    ///
-    /// Width and height are in pixels.
     #[inline]
-    pub fn with_max_dimensions(mut self, width: u32, height: u32) -> WindowBuilder {
-        self.window.max_dimensions = Some((width, height));
+    pub fn with_max_dimensions(mut self, max_size: LogicalSize) -> WindowBuilder {
+        self.window.max_dimensions = Some(max_size);
         self
     }
 
@@ -144,14 +142,15 @@ impl WindowBuilder {
     ///
     /// Error should be very rare and only occur in case of permission denied, incompatible system,
     /// out of memory, etc.
+    #[inline]
     pub fn build(mut self, events_loop: &EventsLoop) -> Result<Window, CreationError> {
         self.window.dimensions = Some(self.window.dimensions.unwrap_or_else(|| {
             if let Some(ref monitor) = self.window.fullscreen {
                 // resizing the window to the dimensions of the monitor when fullscreen
-                monitor.get_dimensions()
+                LogicalSize::from_physical(monitor.get_dimensions(), 1.0)
             } else {
                 // default dimensions
-                (1024, 768)
+                (1024, 768).into()
             }
         }));
 
@@ -219,7 +218,7 @@ impl Window {
     ///
     /// Returns `None` if the window no longer exists.
     #[inline]
-    pub fn get_position(&self) -> Option<(i32, i32)> {
+    pub fn get_position(&self) -> Option<LogicalPosition> {
         self.window.get_position()
     }
 
@@ -228,7 +227,7 @@ impl Window {
     ///
     /// The same conditions that apply to `get_position` apply to this method.
     #[inline]
-    pub fn get_inner_position(&self) -> Option<(i32, i32)> {
+    pub fn get_inner_position(&self) -> Option<LogicalPosition> {
         self.window.get_inner_position()
     }
 
@@ -238,61 +237,30 @@ impl Window {
     ///
     /// This is a no-op if the window has already been closed.
     #[inline]
-    pub fn set_position(&self, x: i32, y: i32) {
-        self.window.set_position(x, y)
+    pub fn set_position(&self, position: LogicalPosition) {
+        self.window.set_position(position)
     }
 
-    /// Returns the size in pixels of the client area of the window.
+    /// Returns the logical size of the window's client area.
     ///
     /// The client area is the content of the window, excluding the title bar and borders.
-    /// These are the dimensions that need to be supplied to `glViewport`.
+    ///
+    /// Converting the returned `LogicalSize` to `PhysicalSize` produces the size your framebuffer should be.
     ///
     /// Returns `None` if the window no longer exists.
     #[inline]
-    pub fn get_inner_size(&self) -> Option<(u32, u32)> {
+    pub fn get_inner_size(&self) -> Option<LogicalSize> {
         self.window.get_inner_size()
     }
 
-    /// Returns the size in points of the client area of the window.
+    /// Returns the logical size of the entire window.
     ///
-    /// The client area is the content of the window, excluding the title bar and borders.
-    /// To get the dimensions of the frame buffer when calling `glViewport`, multiply with hidpi factor.
-    ///
-    /// Returns `None` if the window no longer exists.
-    ///
-    /// DEPRECATED
-    #[inline]
-    #[deprecated]
-    pub fn get_inner_size_points(&self) -> Option<(u32, u32)> {
-        self.window.get_inner_size().map(|(x, y)| {
-            let hidpi = self.hidpi_factor();
-            ((x as f32 / hidpi) as u32, (y as f32 / hidpi) as u32)
-        })
-    }
-
-    /// Returns the size in pixels of the client area of the window.
-    ///
-    /// The client area is the content of the window, excluding the title bar and borders.
-    /// These are the dimensions of the frame buffer, and the dimensions that you should use
-    ///  when you call `glViewport`.
-    ///
-    /// Returns `None` if the window no longer exists.
-    ///
-    /// DEPRECATED
-    #[inline]
-    #[deprecated]
-    pub fn get_inner_size_pixels(&self) -> Option<(u32, u32)> {
-        self.window.get_inner_size()
-    }
-
-    /// Returns the size in pixels of the window.
-    ///
-    /// These dimensions include title bar and borders. If you don't want these, you should use
-    ///  use `get_inner_size` instead.
+    /// These dimensions include the title bar and borders. If you don't want that (and you usually don't),
+    /// use `get_inner_size` instead.
     ///
     /// Returns `None` if the window no longer exists.
     #[inline]
-    pub fn get_outer_size(&self) -> Option<(u32, u32)> {
+    pub fn get_outer_size(&self) -> Option<LogicalSize> {
         self.window.get_outer_size()
     }
 
@@ -302,23 +270,19 @@ impl Window {
     ///
     /// This is a no-op if the window has already been closed.
     #[inline]
-    pub fn set_inner_size(&self, x: u32, y: u32) {
-        self.window.set_inner_size(x, y)
+    pub fn set_inner_size(&self, size: LogicalSize) {
+        self.window.set_inner_size(size)
     }
 
     /// Sets a minimum dimension size for the window.
-    ///
-    /// Width and height are in pixels.
     #[inline]
-    pub fn set_min_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_min_dimensions(&self, dimensions: Option<LogicalSize>) {
         self.window.set_min_dimensions(dimensions)
     }
 
     /// Sets a maximum dimension size for the window.
-    ///
-    /// Width and height are in pixels.
     #[inline]
-    pub fn set_max_dimensions(&self, dimensions: Option<(u32, u32)>) {
+    pub fn set_max_dimensions(&self, dimensions: Option<LogicalSize>) {
         self.window.set_max_dimensions(dimensions)
     }
 
@@ -337,46 +301,30 @@ impl Window {
         self.window.set_resizable(resizable)
     }
 
-    /// DEPRECATED. Gets the native platform specific display for this window.
-    /// This is typically only required when integrating with
-    /// other libraries that need this information.
-    #[deprecated]
+    /// Returns the DPI factor that can be used to map logical pixels to physical pixels, and vice versa.
+    ///
+    /// See the [`dpi`](dpi/index.html) module for more information.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **X11:** Can be overridden using the `WINIT_HIDPI_FACTOR` environment variable.
+    /// - **Android:** Always returns 1.0.
     #[inline]
-    pub unsafe fn platform_display(&self) -> *mut libc::c_void {
-        self.window.platform_display()
-    }
-
-    /// DEPRECATED. Gets the native platform specific window handle. This is
-    /// typically only required when integrating with other libraries
-    /// that need this information.
-    #[deprecated]
-    #[inline]
-    pub unsafe fn platform_window(&self) -> *mut libc::c_void {
-        self.window.platform_window()
+    pub fn get_hidpi_factor(&self) -> f64 {
+        self.window.get_hidpi_factor()
     }
 
     /// Modifies the mouse cursor of the window.
     /// Has no effect on Android.
+    #[inline]
     pub fn set_cursor(&self, cursor: MouseCursor) {
         self.window.set_cursor(cursor);
     }
 
-    /// Returns the ratio between the backing framebuffer resolution and the
-    /// window size in screen pixels. This is typically one for a normal display
-    /// and two for a retina display.
-    ///
-    /// ## Platform-specific
-    /// On X11 the DPI factor can be overridden using the `WINIT_HIDPI_FACTOR` environment
-    /// variable.
-    #[inline]
-    pub fn hidpi_factor(&self) -> f32 {
-        self.window.hidpi_factor()
-    }
-
     /// Changes the position of the cursor in window coordinates.
     #[inline]
-    pub fn set_cursor_position(&self, x: i32, y: i32) -> Result<(), ()> {
-        self.window.set_cursor_position(x, y)
+    pub fn set_cursor_position(&self, position: LogicalPosition) -> Result<(), ()> {
+        self.window.set_cursor_position(position)
     }
 
     /// Sets how winit handles the cursor. See the documentation of `CursorState` for details.
@@ -426,11 +374,12 @@ impl Window {
 
     /// Sets location of IME candidate box in client area coordinates relative to the top left.
     #[inline]
-    pub fn set_ime_spot(&self, x: i32, y: i32) {
-        self.window.set_ime_spot(x, y)
+    pub fn set_ime_spot(&self, position: LogicalPosition) {
+        self.window.set_ime_spot(position)
     }
 
     /// Returns the monitor on which the window currently resides
+    #[inline]
     pub fn get_current_monitor(&self) -> MonitorId {
         self.window.get_current_monitor()
     }
@@ -477,26 +426,29 @@ impl MonitorId {
         self.inner.get_name()
     }
 
-    /// Returns the number of pixels currently displayed on the monitor.
+    /// Returns the monitor's resolution.
     #[inline]
-    pub fn get_dimensions(&self) -> (u32, u32) {
+    pub fn get_dimensions(&self) -> PhysicalSize {
         self.inner.get_dimensions()
     }
 
     /// Returns the top-left corner position of the monitor relative to the larger full
     /// screen area.
     #[inline]
-    pub fn get_position(&self) -> (i32, i32) {
+    pub fn get_position(&self) -> PhysicalPosition {
         self.inner.get_position()
     }
 
-    /// Returns the ratio between the monitor's physical pixels and logical pixels.
+    /// Returns the DPI factor that can be used to map logical pixels to physical pixels, and vice versa.
+    ///
+    /// See the [`dpi`](dpi/index.html) module for more information.
     ///
     /// ## Platform-specific
-    /// On X11 the DPI factor can be overridden using the `WINIT_HIDPI_FACTOR` environment
-    /// variable.
+    ///
+    /// - **X11:** Can be overridden using the `WINIT_HIDPI_FACTOR` environment variable.
+    /// - **Android:** Always returns 1.0.
     #[inline]
-    pub fn get_hidpi_factor(&self) -> f32 {
+    pub fn get_hidpi_factor(&self) -> f64 {
         self.inner.get_hidpi_factor()
     }
 }