gpui(web): Fix crash when resizing on firefox-linux (#50419)

Owen Law created 1 month ago

Fixes a crash which occurred on firefox-linux when resizing (and was
causing blanks during resize in other browsers)

The issue was due to attempting to resize the drawing buffer while it
was being rendered to, which causes a browser crash since firefox
destroys that buffer while it is still being accessed. This essentially
defers the resize to just before drawing, so that it won't be resized
*while* being drawn to.

Release Notes:

- N/A

Change summary

crates/gpui_web/src/window.rs | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)

Detailed changes

crates/gpui_web/src/window.rs

@@ -54,6 +54,7 @@ pub(crate) struct WebWindowInner {
     pub(crate) last_physical_size: Cell<(u32, u32)>,
     pub(crate) notify_scale: Cell<bool>,
     mql_handle: RefCell<Option<MqlHandle>>,
+    pending_physical_size: Cell<Option<(u32, u32)>>,

 }
 
 pub struct WebWindow {
@@ -163,6 +164,7 @@ impl WebWindow {
             last_physical_size: Cell::new((0, 0)),
             notify_scale: Cell::new(false),
             mql_handle: RefCell::new(None),
+            pending_physical_size: Cell::new(None),

         });
 
         let raf_closure = inner.create_raf_closure();
@@ -252,8 +254,9 @@ impl WebWindow {
             let clamped_width = physical_width.min(max_texture_dimension);
             let clamped_height = physical_height.min(max_texture_dimension);
 
-            inner.canvas.set_width(clamped_width);

-            inner.canvas.set_height(clamped_height);

+            inner

+                .pending_physical_size

+                .set(Some((clamped_width, clamped_height)));

 
             {
                 let mut s = inner.state.borrow_mut();
@@ -262,10 +265,6 @@ impl WebWindow {
                     height: px(logical_height),
                 };
                 s.scale_factor = dpr_f32;
-                s.renderer.update_drawable_size(Size {

-                    width: DevicePixels(clamped_width as i32),

-                    height: DevicePixels(clamped_height as i32),

-                });

             }
 
             let new_size = Size {
@@ -637,6 +636,20 @@ impl PlatformWindow for WebWindow {
     }
 
     fn draw(&self, scene: &Scene) {
+        if let Some((width, height)) = self.inner.pending_physical_size.take() {

+            if self.inner.canvas.width() != width || self.inner.canvas.height() != height {

+                self.inner.canvas.set_width(width);

+                self.inner.canvas.set_height(height);

+            }

+

+            let mut state = self.inner.state.borrow_mut();

+            state.renderer.update_drawable_size(Size {

+                width: DevicePixels(width as i32),

+                height: DevicePixels(height as i32),

+            });

+            drop(state);

+        }

+

         self.inner.state.borrow_mut().renderer.draw(scene);
     }