Remove context creation code. Add mpsc Message channel.

Cargo.toml

@@ -10,30 +10,18 @@ authors = [
 ]
 edition = "2018"
 
-[features]
-default = ["gl_renderer"]
-gl_renderer = ["gl"]
-wgpu_renderer = ["wgpu"]
-
 [dependencies]
-log = "0.4.8"
+log = "0.4.11"
-
+raw-window-handle = "0.3.3"
-[dependencies.gl]
-gl = "0.14"
-optional = true
-
-[dependencies.wgpu]
-wgpu = "0.6"
-optional = true
 
 [target.'cfg(target_os="linux")'.dependencies]
 xcb = { version = "0.9", features = ["thread", "xlib_xcb", "dri2"] }
-x11 = { version = "2.18", features = ["xlib", "glx"] }
+x11 = { version = "2.18", features = ["xlib"] }
 libc = "0.2"
 
 [target.'cfg(target_os="windows")'.dependencies]
 winapi = { version = "0.3.8", features = ["libloaderapi", "winuser", "windef", "minwindef", "guiddef", "combaseapi", "wingdi", "errhandlingapi"] }
 
 [target.'cfg(target_os="macos")'.dependencies]
-cocoa = "0.20.1"
+cocoa = "0.23.0"
 objc = "0.2.7"

examples/open_window.rs

@@ -1,3 +1,5 @@
+use std::sync::mpsc;
+
 use baseview::Message;
 
 fn main() {
@@ -8,15 +10,22 @@ fn main() {
         parent: baseview::Parent::None,
     };
 
+    let (message_tx, message_rx) = mpsc::channel::<Message>();
+
     let my_program = MyProgram {};
 
-    baseview::Window::open(window_open_options, my_program);
+    let window = baseview::Window::build(window_open_options, message_tx);
-}
 
+    // Get raw window handle!
+    let _raw_handle = window.raw_window_handle();
+
+    my_program_loop(my_program, message_rx);
+}
 struct MyProgram {}
 
-impl baseview::Receiver for MyProgram {
+fn my_program_loop(_my_program: MyProgram, message_rx: mpsc::Receiver<Message>) {
-    fn on_message(&mut self, message: Message) {
+    loop {
+        let message = message_rx.recv().unwrap();
         match message {
             Message::CursorMotion(x, y) => {
                 println!("Cursor moved, x: {}, y: {}", x, y);

src/lib.rs

@@ -32,7 +32,3 @@ pub struct WindowOpenOptions<'a> {
 
     pub parent: Parent,
 }
-
-pub trait Receiver {
-    fn on_message(&mut self, message: Message);
-}

src/macos/window.rs

@@ -8,12 +8,10 @@ use cocoa::foundation::{NSAutoreleasePool, NSPoint, NSRect, NSSize, NSString};
 
 use crate::{Message, MouseButtonID, MouseScroll, Receiver, WindowOpenOptions};
 
-pub struct Window<R: Receiver> {
+pub struct Window {}
-    receiver: R,
-}
 
-impl<R: Receiver> Window<R> {
+impl Window {
-    pub fn open(options: WindowOpenOptions, receiver: R) -> Self {
+    pub fn open(options: WindowOpenOptions, message_tx: mpsc::Sender<Message>) -> Self {
         unsafe {
             let _pool = NSAutoreleasePool::new(nil);
 
@@ -44,11 +42,13 @@ impl<R: Receiver> Window<R> {
             current_app.activateWithOptions_(NSApplicationActivateIgnoringOtherApps);
             app.run();
 
-            receiver.on_message(Message::Opened(crate::message::WindowInfo {
+            message_tx
+                .send(Message::Opened(WindowInfo {
                     width: options.width as u32,
                     height: options.height as u32,
                     dpi: None,
-            }));
+                }))
+                .unwrap();
 
             Window { receiver }
         }

src/win/window.rs

@@ -2,6 +2,7 @@ extern crate winapi;
 
 use std::ffi::CString;
 use std::ptr::null_mut;
+use std::sync::mpsc;
 
 use self::winapi::shared::guiddef::GUID;
 use self::winapi::shared::minwindef::{ATOM, FALSE, LPARAM, LRESULT, UINT, WPARAM};
@@ -112,20 +113,19 @@ unsafe fn unregister_wnd_class(wnd_class: ATOM) {
 
 unsafe fn init_gl_context() {}
 
-pub struct Window<R: Receiver> {
+pub struct Window {
     pub(crate) hwnd: HWND,
     hdc: HDC,
     gl_context: HGLRC,
     window_class: ATOM,
-    receiver: R,
     scaling: Option<f64>, // DPI scale, 96.0 is "default".
     r: f32,
     g: f32,
     b: f32,
 }
 
-impl<R: Receiver> Window<R> {
+impl Window {
-    pub fn open(options: WindowOpenOptions, receiver: R) {
+    pub fn open(options: WindowOpenOptions, message_tx: mpsc::Sender<Message>) {
         unsafe {
             let mut window = Window {
                 hwnd: null_mut(),
@@ -241,13 +241,13 @@ impl<R: Receiver> Window<R> {
 
             SetTimer(hwnd, 4242, 13, None);
 
-            window
+            message_tx
-                .receiver
+                .send(Message::Opened(WindowInfo {
-                .on_message(Message::Opened(crate::message::WindowInfo {
                     width: options.width as u32,
                     height: options.height as u32,
-                    dpi: window.scaling,
+                    dpi: None,
-                }));
+                }))
+                .unwrap();
 
             // todo: decide what to do with the message pump
             if parent.is_null() {

src/x11/mod.rs

@@ -3,6 +3,3 @@ use xcb_connection::XcbConnection;
 
 mod window;
 pub use window::*;
-
-#[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
-mod opengl_util;

src/x11/opengl_util.rs

@@ -1,182 +0,0 @@
-use std::ffi::{CStr, CString};
-use std::os::raw::{c_int, c_void};
-use std::ptr::null_mut;
-
-use ::x11::{glx, xlib};
-
-use super::XcbConnection;
-
-pub fn fb_config(xcb_connection: &XcbConnection) -> *mut glx::__GLXFBConfigRec {
-    // Check GLX version (>= 1.3 needed)
-    check_glx_version(&xcb_connection);
-
-    // Get GLX framebuffer config (requires GLX >= 1.3)
-    #[rustfmt::skip]
-    let fb_config = get_glxfbconfig(
-        &xcb_connection,
-        &[
-            glx::GLX_X_RENDERABLE,  1,
-            glx::GLX_DRAWABLE_TYPE, glx::GLX_WINDOW_BIT,
-            glx::GLX_RENDER_TYPE,   glx::GLX_RGBA_BIT,
-            glx::GLX_X_VISUAL_TYPE, glx::GLX_TRUE_COLOR,
-            glx::GLX_RED_SIZE,      8,
-            glx::GLX_GREEN_SIZE,    8,
-            glx::GLX_BLUE_SIZE,     8,
-            glx::GLX_ALPHA_SIZE,    8,
-            glx::GLX_DEPTH_SIZE,    24,
-            glx::GLX_STENCIL_SIZE,  8,
-            glx::GLX_DOUBLEBUFFER,  1,
-            0
-        ],
-    );
-
-    fb_config
-}
-
-pub fn x_visual_info(
-    xcb_connection: &XcbConnection,
-    fb_config: *mut glx::__GLXFBConfigRec,
-) -> *const xlib::XVisualInfo {
-    // The GLX framebuffer config holds an XVisualInfo, which we'll need for other X operations.
-
-    unsafe { glx::glXGetVisualFromFBConfig(xcb_connection.conn.get_raw_dpy(), fb_config) }
-}
-
-pub fn glx_context(
-    xcb_connection: &XcbConnection,
-    fb_config: *mut glx::__GLXFBConfigRec,
-) -> *mut glx::__GLXcontextRec {
-    // Load GLX extensions
-    // We need at least `GLX_ARB_create_context`
-    let glx_extensions = unsafe {
-        CStr::from_ptr(glx::glXQueryExtensionsString(
-            xcb_connection.conn.get_raw_dpy(),
-            xcb_connection.xlib_display,
-        ))
-        .to_str()
-        .unwrap()
-    };
-    glx_extensions
-        .find("GLX_ARB_create_context")
-        .expect("could not find GLX extension GLX_ARB_create_context");
-
-    // With GLX, we don't need a context pre-created in order to load symbols.
-    // Otherwise, we would need to create a temporary legacy (dummy) GL context to load them.
-    // (something that has at least GlXCreateContextAttribsARB)
-    let glx_create_context_attribs: GlXCreateContextAttribsARBProc =
-        unsafe { std::mem::transmute(load_gl_func("glXCreateContextAttribsARB")) };
-
-    // Load all other symbols
-    unsafe {
-        gl::load_with(|n| load_gl_func(&n));
-    }
-
-    // Check GL3 support
-    if !gl::GenVertexArrays::is_loaded() {
-        panic!("no GL3 support available!");
-    }
-
-    // Create GLX context attributes. (?)
-    let context_attribs: [c_int; 5] = [
-        glx::arb::GLX_CONTEXT_MAJOR_VERSION_ARB as c_int,
-        3,
-        glx::arb::GLX_CONTEXT_MINOR_VERSION_ARB as c_int,
-        0,
-        0,
-    ];
-    let ctx = unsafe {
-        glx_create_context_attribs(
-            xcb_connection.conn.get_raw_dpy(),
-            fb_config,
-            null_mut(),
-            xlib::True,
-            &context_attribs[0] as *const c_int,
-        )
-    };
-
-    if ctx.is_null()
-    /* || ctx_error_occurred */
-    {
-        panic!("Error when creating a GL 3.0 context");
-    }
-    if unsafe { glx::glXIsDirect(xcb_connection.conn.get_raw_dpy(), ctx) } == 0 {
-        panic!("Obtained indirect rendering context");
-    }
-
-    ctx
-}
-
-pub type GlXCreateContextAttribsARBProc = unsafe extern "C" fn(
-    dpy: *mut xlib::Display,
-    fbc: glx::GLXFBConfig,
-    share_context: glx::GLXContext,
-    direct: xlib::Bool,
-    attribs: *const c_int,
-) -> glx::GLXContext;
-
-// Check to make sure this system supports the correct version of GLX (>= 1.3 for now)
-// For now it just panics if not, but TODO: do correct error handling
-fn check_glx_version(xcb_connection: &XcbConnection) {
-    let raw_display = xcb_connection.conn.get_raw_dpy();
-    let mut maj: c_int = 0;
-    let mut min: c_int = 0;
-
-    unsafe {
-        if glx::glXQueryVersion(raw_display, &mut maj as *mut c_int, &mut min as *mut c_int) == 0 {
-            panic!("Cannot get GLX version");
-        }
-        if (maj < 1) || (maj == 1 && min < 3) {
-            panic!("GLX version >= 1.3 required! (have {}.{})", maj, min);
-        }
-    }
-}
-
-// Get GLX framebuffer config
-// History: https://stackoverflow.com/questions/51558473/whats-the-difference-between-a-glx-visual-and-a-fbconfig
-fn get_glxfbconfig(xcb_connection: &XcbConnection, visual_attribs: &[i32]) -> glx::GLXFBConfig {
-    let raw_display = xcb_connection.conn.get_raw_dpy();
-    let xlib_display = xcb_connection.xlib_display;
-
-    unsafe {
-        let mut fbcount: c_int = 0;
-        let fbcs = glx::glXChooseFBConfig(
-            raw_display,
-            xlib_display,
-            visual_attribs.as_ptr(),
-            &mut fbcount as *mut c_int,
-        );
-
-        if fbcount == 0 {
-            panic!("Could not find compatible GLX FB config.");
-        }
-
-        // If we get more than one, any of the different configs work. Just choose the first one.
-        let fbc = *fbcs;
-        xlib::XFree(fbcs as *mut c_void);
-        fbc
-    }
-}
-
-pub unsafe fn load_gl_func(name: &str) -> *mut c_void {
-    let cname = CString::new(name).unwrap();
-    let ptr: *mut c_void = std::mem::transmute(glx::glXGetProcAddress(cname.as_ptr() as *const u8));
-    if ptr.is_null() {
-        panic!("could not load {}", name);
-    }
-    ptr
-}
-
-pub fn xcb_expose(
-    window_id: u32,
-    raw_display: *mut xlib::_XDisplay,
-    ctx: *mut glx::__GLXcontextRec,
-) {
-    unsafe {
-        glx::glXMakeCurrent(raw_display, window_id as xlib::XID, ctx);
-        gl::ClearColor(0.3, 0.8, 0.3, 1.0);
-        gl::Clear(gl::COLOR_BUFFER_BIT);
-        gl::Flush();
-        glx::glXSwapBuffers(raw_display, window_id as xlib::XID);
-        glx::glXMakeCurrent(raw_display, 0, null_mut());
-    }
-}

src/x11/window.rs

@@ -1,34 +1,23 @@
-// TODO: messy for now, will refactor when I have more of an idea of the API/architecture
-// TODO: close window
-// TODO: proper error handling (no bare `unwrap`s, no panics)
-// TODO: move more OpenGL-related stuff into opengl_util.rs
-// TODO: consider researching all unsafe calls here and figuring out what invariants need to be upheld.
-//       (write safe wrappers?)
-
 use std::ffi::CStr;
-use std::os::raw::{c_int, c_void};
+use std::os::raw::c_void;
-use std::ptr::null_mut;
+use std::sync::mpsc;
+use std::thread;
 
 use ::x11::xlib;
 // use xcb::dri2; // needed later
 
-#[cfg(all(not(feature = "wgpu_renderer"), feature = "gl_renderer"))]
-use super::opengl_util;
-
 use super::XcbConnection;
-use crate::{Message, MouseButtonID, MouseScroll, Parent, Receiver, WindowOpenOptions};
+use crate::{Message, MouseButtonID, MouseScroll, Parent, WindowInfo, WindowOpenOptions};
 
-pub struct Window<R: Receiver> {
+use raw_window_handle::RawWindowHandle;
-    xcb_connection: XcbConnection,
+
+pub struct Window {
     scaling: Option<f64>, // DPI scale, 96.0 is "default".
-    receiver: R,
+    raw_handle: RawWindowHandle,
-
-    #[cfg(all(not(feature = "wgpu_renderer"), feature = "gl_renderer"))]
-    ctx: *mut x11::glx::__GLXcontextRec,
 }
 
-impl<R: Receiver> Window<R> {
+impl Window {
-    pub fn open(options: WindowOpenOptions, receiver: R) -> Self {
+    pub fn build(options: WindowOpenOptions, message_tx: mpsc::Sender<Message>) -> Self {
         // Convert the parent to a X11 window ID if we're given one
         let parent = match options.parent {
             Parent::None => None,
@@ -39,12 +28,6 @@ impl<R: Receiver> Window<R> {
         // Connect to the X server
         let xcb_connection = XcbConnection::new();
 
-        #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
-        let fb_config = opengl_util::fb_config(&xcb_connection);
-        #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
-        let x_visual_info: *const xlib::XVisualInfo =
-            { opengl_util::x_visual_info(&xcb_connection, fb_config) };
-
         // Load up DRI2 extensions.
         // See also: https://www.x.org/releases/X11R7.7/doc/dri2proto/dri2proto.txt
         /*
@@ -60,7 +43,12 @@ impl<R: Receiver> Window<R> {
 
         // Get screen information (?)
         let setup = xcb_connection.conn.get_setup();
-        let screen = unsafe { setup.roots().nth((*x_visual_info).screen as usize).unwrap() };
+        let screen = setup
+            .roots()
+            .nth(xcb_connection.xlib_display as usize)
+            .unwrap();
+
+        let foreground = xcb_connection.conn.generate_id();
 
         // Convert parent into something that X understands
         let parent_id = if let Some(p) = parent {
@@ -69,24 +57,30 @@ impl<R: Receiver> Window<R> {
             screen.root()
         };
 
-        // Create a colormap
+        xcb::create_gc(
-        let colormap = xcb_connection.conn.generate_id();
-        unsafe {
-            xcb::create_colormap(
             &xcb_connection.conn,
-                xcb::COLORMAP_ALLOC_NONE as u8,
+            foreground,
-                colormap,
             parent_id,
-                (*x_visual_info).visualid as u32,
+            &[
+                (xcb::GC_FOREGROUND, screen.black_pixel()),
+                (xcb::GC_GRAPHICS_EXPOSURES, 0),
+            ],
         );
-        }
 
-        // Create window, connecting to the parent if we have one
         let window_id = xcb_connection.conn.generate_id();
-        let cw_values = [
+        xcb::create_window(
-            (xcb::CW_BACK_PIXEL, screen.white_pixel()),
+            &xcb_connection.conn,
-            (xcb::CW_BORDER_PIXEL, screen.black_pixel()),
+            xcb::COPY_FROM_PARENT as u8,
-            (
+            window_id,
+            parent_id,
+            0,
+            0,
+            options.width as u16,
+            options.height as u16,
+            10,
+            xcb::WINDOW_CLASS_INPUT_OUTPUT as u16,
+            screen.root_visual(),
+            &[(
                 xcb::CW_EVENT_MASK,
                 xcb::EVENT_MASK_EXPOSURE
                     | xcb::EVENT_MASK_POINTER_MOTION
@@ -94,40 +88,10 @@ impl<R: Receiver> Window<R> {
                     | xcb::EVENT_MASK_BUTTON_RELEASE
                     | xcb::EVENT_MASK_KEY_PRESS
                     | xcb::EVENT_MASK_KEY_RELEASE,
-            ),
+            )],
-            (xcb::CW_COLORMAP, colormap),
-        ];
-        xcb::create_window(
-            // Connection
-            &xcb_connection.conn,
-            // Depth
-            unsafe { *x_visual_info }.depth as u8,
-            // Window ID
-            window_id,
-            // Parent ID
-            parent_id,
-            // x
-            0,
-            // y
-            0,
-            // width
-            options.width as u16,
-            // height
-            options.height as u16,
-            // border width
-            0,
-            // class
-            xcb::WINDOW_CLASS_INPUT_OUTPUT as u16,
-            // visual
-            unsafe { *x_visual_info }.visualid as u32,
-            // value list
-            &cw_values,
         );
-
+        xcb::map_window(&xcb_connection.conn, window_id);
-        // Don't need the visual info anymore
+        xcb_connection.conn.flush();
-        unsafe {
-            xlib::XFree(x_visual_info as *mut c_void);
-        }
 
         // Change window title
         let title = options.title;
@@ -152,151 +116,55 @@ impl<R: Receiver> Window<R> {
         };
         */
 
-        #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
+        // What does this do?
-        let ctx = opengl_util::glx_context(&xcb_connection, fb_config);
-
-        // Display the window
-        xcb::map_window(&xcb_connection.conn, window_id);
-        xcb_connection.conn.flush();
         unsafe {
             xlib::XSync(xcb_connection.conn.get_raw_dpy(), xlib::False);
         }
 
-        #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
+        let raw_handle = RawWindowHandle::Xcb(raw_window_handle::unix::XcbHandle {
+            connection: xcb_connection.conn.get_raw_conn() as *mut c_void,
+            ..raw_window_handle::unix::XcbHandle::empty()
+        });
+
         let mut x11_window = Self {
-            xcb_connection,
             scaling: None,
-            ctx,
+            raw_handle,
-            receiver,
         };
 
-        x11_window.scaling = x11_window
+        x11_window.scaling =
-            .get_scaling_xft()
+            get_scaling_xft(&xcb_connection).or(get_scaling_screen_dimensions(&xcb_connection));
-            .or(x11_window.get_scaling_screen_dimensions());
         println!("Scale factor: {:?}", x11_window.scaling);
 
-        x11_window
+        message_tx
-            .receiver
+            .send(Message::Opened(WindowInfo {
-            .on_message(Message::Opened(crate::message::WindowInfo {
                 width: options.width as u32,
                 height: options.height as u32,
                 dpi: x11_window.scaling,
-            }));
+            }))
+            .unwrap();
 
-        x11_window.handle_events(window_id);
+        thread::spawn(move || {
+            run_event_loop(xcb_connection, message_tx);
+        });
 
-        x11_window.receiver.on_message(Message::WillClose);
+        x11_window
-
-        return x11_window;
     }
 
-    // Event loop
+    pub fn raw_window_handle(&self) -> RawWindowHandle {
-    fn handle_events(&mut self, window_id: u32) {
+        self.raw_handle
-        let raw_display = self.xcb_connection.conn.get_raw_dpy();
-        loop {
-            let ev = self.xcb_connection.conn.wait_for_event();
-            if let Some(event) = ev {
-                let event_type = event.response_type() & !0x80;
-
-                // For all of the keyboard and mouse events, you can fetch
-                // `x`, `y`, `detail`, and `state`.
-                // - `x` and `y` are the position inside the window where the cursor currently is
-                //   when the event happened.
-                // - `detail` will tell you which keycode was pressed/released (for keyboard events)
-                //   or which mouse button was pressed/released (for mouse events).
-                //   For mouse events, here's what the value means (at least on my current mouse):
-                //      1 = left mouse button
-                //      2 = middle mouse button (scroll wheel)
-                //      3 = right mouse button
-                //      4 = scroll wheel up
-                //      5 = scroll wheel down
-                //      8 = lower side button ("back" button)
-                //      9 = upper side button ("forward" button)
-                //   Note that you *will* get a "button released" event for even the scroll wheel
-                //   events, which you can probably ignore.
-                // - `state` will tell you the state of the main three mouse buttons and some of
-                //   the keyboard modifier keys at the time of the event.
-                //   http://rtbo.github.io/rust-xcb/src/xcb/ffi/xproto.rs.html#445
-
-                match event_type {
-                    xcb::EXPOSE => {
-                        #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
-                        opengl_util::xcb_expose(window_id, raw_display, self.ctx);
-                    }
-                    xcb::MOTION_NOTIFY => {
-                        let event = unsafe { xcb::cast_event::<xcb::MotionNotifyEvent>(&event) };
-                        let detail = event.detail();
-
-                        if detail != 4 && detail != 5 {
-                            self.receiver.on_message(Message::CursorMotion(
-                                event.event_x() as i32,
-                                event.event_y() as i32,
-                            ));
-                        }
-                    }
-                    xcb::BUTTON_PRESS => {
-                        let event = unsafe { xcb::cast_event::<xcb::ButtonPressEvent>(&event) };
-                        let detail = event.detail();
-
-                        match detail {
-                            4 => {
-                                self.receiver.on_message(Message::MouseScroll(MouseScroll {
-                                    x_delta: 0.0,
-                                    y_delta: 1.0,
-                                }));
-                            }
-                            5 => {
-                                self.receiver.on_message(Message::MouseScroll(MouseScroll {
-                                    x_delta: 0.0,
-                                    y_delta: -1.0,
-                                }));
-                            }
-                            detail => {
-                                let button_id = mouse_id(detail);
-                                self.receiver.on_message(Message::MouseDown(button_id));
-                            }
-                        }
-                    }
-                    xcb::BUTTON_RELEASE => {
-                        let event = unsafe { xcb::cast_event::<xcb::ButtonPressEvent>(&event) };
-                        let detail = event.detail();
-
-                        if detail != 4 && detail != 5 {
-                            let button_id = mouse_id(detail);
-                            self.receiver.on_message(Message::MouseUp(button_id));
-                        }
-                    }
-                    xcb::KEY_PRESS => {
-                        let event = unsafe { xcb::cast_event::<xcb::KeyPressEvent>(&event) };
-                        let detail = event.detail();
-
-                        self.receiver.on_message(Message::KeyDown(detail));
-                    }
-                    xcb::KEY_RELEASE => {
-                        let event = unsafe { xcb::cast_event::<xcb::KeyReleaseEvent>(&event) };
-                        let detail = event.detail();
-
-                        self.receiver.on_message(Message::KeyUp(detail));
-                    }
-                    _ => {
-                        println!("Unhandled event type: {:?}", event_type);
-                    }
-                }
-            }
     }
 }
 
 // Try to get the scaling with this function first.
 // If this gives you `None`, fall back to `get_scaling_screen_dimensions`.
 // If neither work, I guess just assume 96.0 and don't do any scaling.
-    fn get_scaling_xft(&self) -> Option<f64> {
+fn get_scaling_xft(xcb_connection: &XcbConnection) -> Option<f64> {
     use std::ffi::CString;
     use x11::xlib::{
-            XResourceManagerString, XrmDestroyDatabase, XrmGetResource, XrmGetStringDatabase,
+        XResourceManagerString, XrmDestroyDatabase, XrmGetResource, XrmGetStringDatabase, XrmValue,
-            XrmValue,
     };
 
-        let display = self.xcb_connection.conn.get_raw_dpy();
+    let display = xcb_connection.conn.get_raw_dpy();
     unsafe {
         let rms = XResourceManagerString(display);
         if !rms.is_null() {
@@ -340,12 +208,12 @@ impl<R: Receiver> Window<R> {
 // Try to get the scaling with `get_scaling_xft` first.
 // Only use this function as a fallback.
 // If neither work, I guess just assume 96.0 and don't do any scaling.
-    fn get_scaling_screen_dimensions(&self) -> Option<f64> {
+fn get_scaling_screen_dimensions(xcb_connection: &XcbConnection) -> Option<f64> {
     // Figure out screen information
-        let setup = self.xcb_connection.conn.get_setup();
+    let setup = xcb_connection.conn.get_setup();
     let screen = setup
         .roots()
-            .nth(self.xcb_connection.xlib_display as usize)
+        .nth(xcb_connection.xlib_display as usize)
         .unwrap();
 
     // Get the DPI from the screen struct
@@ -364,6 +232,107 @@ impl<R: Receiver> Window<R> {
     // TODO: choose between `xres` and `yres`? (probably both are the same?)
     Some(yres)
 }
+
+// Event loop
+fn run_event_loop(xcb_connection: XcbConnection, message_tx: mpsc::Sender<Message>) {
+    //let raw_display = self.xcb_connection.conn.get_raw_dpy();
+    loop {
+        let ev = xcb_connection.conn.wait_for_event();
+        if let Some(event) = ev {
+            let event_type = event.response_type() & !0x80;
+
+            // For all of the keyboard and mouse events, you can fetch
+            // `x`, `y`, `detail`, and `state`.
+            // - `x` and `y` are the position inside the window where the cursor currently is
+            //   when the event happened.
+            // - `detail` will tell you which keycode was pressed/released (for keyboard events)
+            //   or which mouse button was pressed/released (for mouse events).
+            //   For mouse events, here's what the value means (at least on my current mouse):
+            //      1 = left mouse button
+            //      2 = middle mouse button (scroll wheel)
+            //      3 = right mouse button
+            //      4 = scroll wheel up
+            //      5 = scroll wheel down
+            //      8 = lower side button ("back" button)
+            //      9 = upper side button ("forward" button)
+            //   Note that you *will* get a "button released" event for even the scroll wheel
+            //   events, which you can probably ignore.
+            // - `state` will tell you the state of the main three mouse buttons and some of
+            //   the keyboard modifier keys at the time of the event.
+            //   http://rtbo.github.io/rust-xcb/src/xcb/ffi/xproto.rs.html#445
+
+            match event_type {
+                xcb::EXPOSE => {
+                    #[cfg(all(feature = "gl_renderer", not(feature = "wgpu_renderer")))]
+                    opengl_util::xcb_expose(window_id, raw_display, self.ctx);
+                }
+                xcb::MOTION_NOTIFY => {
+                    let event = unsafe { xcb::cast_event::<xcb::MotionNotifyEvent>(&event) };
+                    let detail = event.detail();
+
+                    if detail != 4 && detail != 5 {
+                        message_tx
+                            .send(Message::CursorMotion(
+                                event.event_x() as i32,
+                                event.event_y() as i32,
+                            ))
+                            .unwrap();
+                    }
+                }
+                xcb::BUTTON_PRESS => {
+                    let event = unsafe { xcb::cast_event::<xcb::ButtonPressEvent>(&event) };
+                    let detail = event.detail();
+
+                    match detail {
+                        4 => {
+                            message_tx
+                                .send(Message::MouseScroll(MouseScroll {
+                                    x_delta: 0.0,
+                                    y_delta: 1.0,
+                                }))
+                                .unwrap();
+                        }
+                        5 => {
+                            message_tx
+                                .send(Message::MouseScroll(MouseScroll {
+                                    x_delta: 0.0,
+                                    y_delta: -1.0,
+                                }))
+                                .unwrap();
+                        }
+                        detail => {
+                            let button_id = mouse_id(detail);
+                            message_tx.send(Message::MouseDown(button_id)).unwrap();
+                        }
+                    }
+                }
+                xcb::BUTTON_RELEASE => {
+                    let event = unsafe { xcb::cast_event::<xcb::ButtonPressEvent>(&event) };
+                    let detail = event.detail();
+
+                    if detail != 4 && detail != 5 {
+                        let button_id = mouse_id(detail);
+                        message_tx.send(Message::MouseUp(button_id)).unwrap();
+                    }
+                }
+                xcb::KEY_PRESS => {
+                    let event = unsafe { xcb::cast_event::<xcb::KeyPressEvent>(&event) };
+                    let detail = event.detail();
+
+                    message_tx.send(Message::KeyDown(detail)).unwrap();
+                }
+                xcb::KEY_RELEASE => {
+                    let event = unsafe { xcb::cast_event::<xcb::KeyReleaseEvent>(&event) };
+                    let detail = event.detail();
+
+                    message_tx.send(Message::KeyUp(detail)).unwrap();
+                }
+                _ => {
+                    println!("Unhandled event type: {:?}", event_type);
+                }
+            }
+        }
+    }
 }
 
 fn mouse_id(id: u8) -> MouseButtonID {