Add set_mouse_cursor method to X11 Window

Cargo.toml

@@ -16,8 +16,9 @@ raw-window-handle = "0.3.3"
 
 [target.'cfg(target_os="linux")'.dependencies]
 xcb = { version = "0.9", features = ["thread", "xlib_xcb", "dri2"] }
-x11 = { version = "2.18", features = ["xlib"] }
+x11 = { version = "2.18", features = ["xlib", "xcursor"] }
 xcb-util = { version = "0.3", features = ["icccm"] }
+maybe-uninit = "2.0"
 libc = "0.2"
 nix = "0.18"
 

examples/open_window.rs

@@ -13,7 +13,9 @@ impl WindowHandler for MyProgram {
 
     fn on_event(&mut self, _window: &mut Window, event: Event) {
         match event {
-            Event::Mouse(e) => println!("Mouse event: {:?}", e),
+            Event::Mouse(e) => {
+                println!("Mouse event: {:?}", e);
+            },
             Event::Keyboard(e) => println!("Keyboard event: {:?}", e),
             Event::Window(e) => println!("Window event: {:?}", e),
         }

src/mouse_cursor.rs

@@ -1,19 +1,49 @@
-#[derive(Debug, Eq, PartialEq, Clone, Copy, PartialOrd, Ord)]
+#[derive(Debug, Eq, PartialEq, Clone, Copy, PartialOrd, Ord, Hash)]
 pub enum MouseCursor {
-    Idle,
+    Default,
-    Pointer,
+    Hand,
-    Grab,
+    HandGrabbing,
-    Text,
+    Help,
-    Crosshair,
+
-    Working,
-    Grabbing,
-    ResizingHorizontally,
-    ResizingVertically,
     Hidden,
+
+    Text,
+    VerticalText,
+
+    Working,
+    PtrWorking,
+
+    NotAllowed,
+    PtrNotAllowed,
+
+    ZoomIn,
+    ZoomOut,
+
+    Alias,
+    Copy,
+    Move,
+    AllScroll,
+    Cell,
+    Crosshair,
+
+    EResize,
+    NResize,
+    NeResize,
+    NwResize,
+    SResize,
+    SeResize,
+    SwResize,
+    WResize,
+    EwResize,
+    NsResize,
+    NwseResize,
+    NeswResize,
+    ColResize,
+    RowResize,
 }
 
 impl Default for MouseCursor {
     fn default() -> Self {
-        Self::Idle
+        Self::Default
     }
 }

src/x11/window.rs

@@ -1,7 +1,8 @@
-use std::os::raw::{c_ulong, c_void};
+use std::os::raw::{c_ulong, c_void, c_char};
-use std::sync::mpsc;
+use std::sync::{mpsc, Mutex};
 use std::time::*;
 use std::thread;
+use std::collections::HashMap;
 
 use raw_window_handle::{
     unix::XlibHandle,
@@ -20,6 +21,7 @@ pub struct Window {
     window_id: u32,
     window_info: WindowInfo,
     mouse_cursor: MouseCursor,
+    cursor_cache: HashMap<MouseCursor, c_ulong>,
 
     frame_interval: Duration,
     event_loop_running: bool,
@@ -157,6 +159,7 @@ impl Window {
             window_id,
             window_info,
             mouse_cursor: MouseCursor::default(),
+            cursor_cache: HashMap::new(),
 
             frame_interval: Duration::from_millis(15),
             event_loop_running: false,
@@ -176,32 +179,25 @@ impl Window {
         &self.window_info
     }
 
-    /*
     pub fn set_mouse_cursor(&mut self, mouse_cursor: MouseCursor) {
         if self.mouse_cursor != mouse_cursor {
-            if mouse_cursor == MouseCursor::Hidden {
+            let display = self.xcb_connection.conn.get_raw_dpy();
-                xcb::change_cursor(&self.xcb_connection.conn, xcb::CW_CURSOR, xcb::CURSOR_NONE);
-            } else {
-                let cursor_name = match mouse_cursor {
-                    MouseCursor::Idle => "pointer",
-                    MouseCursor::Pointer => "pointer",
-                    MouseCursor::Grab => "hand1",
-                    MouseCursor::Text => "xterm",
-                    MouseCursor::Crosshair => "crosshair",
-                    MouseCursor::Working => "watch",
-                    MouseCursor::Grabbing => "hand2",
-                    MouseCursor::ResizingHorizontally => "sizing",
-                    MouseCursor::ResizingVertically => "sizing",
-                    _ => "pointer",
-                };
-            }
 
-            
+            let cursor = *self
+                .cursor_cache
+                .entry(mouse_cursor)
+                .or_insert_with(|| get_cursor(display, mouse_cursor));
+
+            unsafe {
+                if cursor != 0 {
+                    x11::xlib::XDefineCursor(display, self.window_id as c_ulong, cursor);
+                }
+                x11::xlib::XFlush(display);
+            }
 
             self.mouse_cursor = mouse_cursor;
         }
     }
-    */
 
     #[inline]
     fn drain_xcb_events<H: WindowHandler>(&mut self, handler: &mut H) {
@@ -430,3 +426,104 @@ fn mouse_id(id: u8) -> MouseButton {
         id => MouseButton::Other(id),
     }
 }
+
+fn load_cursor(display: *mut x11::xlib::Display, name: &[u8]) -> c_ulong {
+    unsafe {
+        x11::xcursor::XcursorLibraryLoadCursor(display, name.as_ptr() as *const c_char)
+    }
+}
+
+fn load_first_existing_cursor(display: *mut x11::xlib::Display, names: &[&[u8]]) -> c_ulong {
+    for name in names.iter() {
+        let xcursor = load_cursor(display, name);
+        if xcursor != 0 {
+            return xcursor;
+        }
+    }
+    0
+}
+
+fn get_cursor(display: *mut x11::xlib::Display, cursor: MouseCursor) -> c_ulong {
+    let load = |name: &[u8]| load_cursor(display, name);
+    let loadn = |names: &[&[u8]]| load_first_existing_cursor(display, names);
+
+    let mut cursor = match cursor {
+        MouseCursor::Default => load(b"left_ptr\0"),
+        MouseCursor::Hand => loadn(&[b"hand2\0", b"hand1\0"]),
+        MouseCursor::HandGrabbing => loadn(&[b"closedhand\0", b"grabbing\0"]),
+        MouseCursor::Help => load(b"question_arrow\0"),
+
+        MouseCursor::Hidden => create_empty_cursor(display),
+
+        MouseCursor::Text => loadn(&[b"text\0", b"xterm\0"]),
+        MouseCursor::VerticalText => load(b"vertical-text\0"),
+
+        MouseCursor::Working => load(b"watch\0"),
+        MouseCursor::PtrWorking => load(b"left_ptr_watch\0"),
+
+        MouseCursor::NotAllowed => load(b"crossed_circle\0"),
+        MouseCursor::PtrNotAllowed => loadn(&[b"no-drop\0", b"crossed_circle\0"]),
+
+        MouseCursor::ZoomIn => load(b"zoom-in\0"),
+        MouseCursor::ZoomOut => load(b"zoom-out\0"),
+
+        MouseCursor::Alias => load(b"link\0"),
+        MouseCursor::Copy => load(b"copy\0"),
+        MouseCursor::Move => load(b"move\0"),
+        MouseCursor::AllScroll => load(b"all-scroll\0"),
+        MouseCursor::Cell => load(b"plus\0"),
+        MouseCursor::Crosshair => load(b"crosshair\0"),
+
+        MouseCursor::EResize => load(b"right_side\0"),
+        MouseCursor::NResize => load(b"top_side\0"),
+        MouseCursor::NeResize => load(b"top_right_corner\0"),
+        MouseCursor::NwResize => load(b"top_left_corner\0"),
+        MouseCursor::SResize => load(b"bottom_side\0"),
+        MouseCursor::SeResize => load(b"bottom_right_corner\0"),
+        MouseCursor::SwResize => load(b"bottom_left_corner\0"),
+        MouseCursor::WResize => load(b"left_side\0"),
+        MouseCursor::EwResize => load(b"h_double_arrow\0"),
+        MouseCursor::NsResize => load(b"v_double_arrow\0"),
+        MouseCursor::NwseResize => loadn(&[b"bd_double_arrow\0", b"size_bdiag\0"]),
+        MouseCursor::NeswResize => loadn(&[b"fd_double_arrow\0", b"size_fdiag\0"]),
+        MouseCursor::ColResize => loadn(&[b"split_h\0", b"h_double_arrow\0"]),
+        MouseCursor::RowResize => loadn(&[b"split_v\0", b"v_double_arrow\0"]),
+    };
+
+    if cursor == 0 {
+        cursor = load(b"left_ptr\0")
+    }
+
+    cursor
+}
+
+fn create_empty_cursor(display: *mut x11::xlib::Display,) -> c_ulong {
+    let data = 0;
+    let pixmap = unsafe {
+        let screen = x11::xlib::XDefaultScreen(display);
+        let window = x11::xlib::XRootWindow(display, screen);
+        x11::xlib::XCreateBitmapFromData(display, window, &data, 1, 1)
+    };
+
+    if pixmap == 0 {
+        panic!("failed to allocate pixmap for cursor");
+    }
+
+    unsafe {
+        // We don't care about this color, since it only fills bytes
+        // in the pixmap which are not 0 in the mask.
+        let mut dummy_color = maybe_uninit::MaybeUninit::uninit();
+        let cursor = x11::xlib::XCreatePixmapCursor(
+            display,
+            pixmap,
+            pixmap,
+            dummy_color.as_mut_ptr(),
+            dummy_color.as_mut_ptr(),
+            0,
+            0,
+        );
+        x11::xlib::XFreePixmap(display, pixmap);
+
+        cursor
+    }
+}