gfx: Take advantage of Apple extensions to DMA layers on the Mac.

We have 60 FPS window resizing now.

src/rust-layers

@@ -1 +1 @@
-Subproject commit 8b179c7470984e5544ee3b8c47f654f7c897f88e
+Subproject commit 90a617d9139b505b0fb03838a62a41887d658904

src/rust-opengles

@@ -1 +1 @@
-Subproject commit 18beb006b719100421c24c634386df15f7fbf6bd
+Subproject commit bb99acf0c7351b5e086fbd9e225d64fec3ea7e39

src/servo/gfx/compositor.rs

@@ -9,7 +9,11 @@ struct LayerBuffer {
     cairo_surface: ImageSurface,
 
     draw_target: DrawTarget,
-    size: Size2D<uint>
+
+    size: Size2D<uint>,
+
+    // NB: stride is in pixels, like OpenGL GL_UNPACK_ROW_LENGTH.
+    stride: uint
 }
 
 /**

src/servo/gfx/png_compositor.rs

@@ -54,7 +54,8 @@ pub fn PngCompositor(output: Chan<~[u8]>) -> PngCompositor {
         let layer_buffer = LayerBuffer {
             cairo_surface: cairo_surface.clone(),
             draw_target: move draw_target,
-            size: Size2D(800u, 600u)
+            size: Size2D(800u, 600u),
+            stride: 800
         };
         let layer_buffer = Cell(move layer_buffer);
 

src/servo/gfx/render_layers.rs

@@ -22,14 +22,24 @@ pub fn render_layers(layer: &RenderLayer,
     let mut buffer = move buffer;
     if buffer.size != layer.size {
         // Create a new buffer.
+
+        // Round the width up the nearest 32 pixels for DMA on the Mac.
+        let mut stride = layer.size.width;
+        if stride % 32 != 0 {
+            stride = (stride & !(32 - 1)) + 32;
+        }
+        assert stride % 32 == 0;
+        assert stride >= layer.size.width;
+
         let cairo_surface = ImageSurface(CAIRO_FORMAT_RGB24,
-                                         layer.size.width as c_int,
+                                         stride as c_int,
                                          layer.size.height as c_int);
         let draw_target = DrawTarget(&cairo_surface);
         buffer = LayerBuffer {
             cairo_surface: move cairo_surface,
             draw_target: move draw_target,
-            size: copy layer.size
+            size: copy layer.size,
+            stride: stride
         };
     }
 

src/servo/gfx/render_task.rs

@@ -84,7 +84,8 @@ impl<C: Compositor Send> Renderer<C> {
             let layer_buffer = layer_buffer_cell.take();
             let layer_buffer_channel = layer_buffer_channel_cell.take();
 
-            let layer_buffer = for render_layers(&render_layer, move layer_buffer) |render_layer, layer_buffer| {
+            let layer_buffer = for render_layers(&render_layer, move layer_buffer)
+                    |render_layer, layer_buffer| {
                 let ctx = RenderContext {
                     canvas: layer_buffer,
                     font_cache: self.font_cache

src/servo/platform/osmain.rs

@@ -56,13 +56,13 @@ fn OSMain(dom_event_chan: pipes::SharedChan<Event>) -> OSMain {
 
 /// Cairo surface wrapping to work with layers
 struct CairoSurfaceImageData {
-    cairo_surface: ImageSurface
+    cairo_surface: ImageSurface,
+    size: Size2D<uint>
 }
 
 impl CairoSurfaceImageData : layers::layers::ImageData {
-    fn size() -> Size2D<uint> {
-        Size2D(self.cairo_surface.width() as uint, self.cairo_surface.height() as uint)
-    }
+    fn size() -> Size2D<uint> { self.size }
+    fn stride() -> uint { self.cairo_surface.width() as uint }
     fn format() -> layers::layers::Format { layers::layers::ARGB32Format }
     fn with_data(f: layers::layers::WithDataFn) { f(self.cairo_surface.data()) }
 }
@@ -92,7 +92,7 @@ fn mainloop(mode: Mode, po: comm::Port<Msg>, dom_event_chan: pipes::SharedChan<E
     let context = layers::rendergl::init_render_context();
 
     let image_data = @layers::layers::BasicImageData::new(
-        Size2D(0u, 0u), layers::layers::RGB24Format, ~[]);
+        Size2D(0u, 0u), 0, layers::layers::RGB24Format, ~[]);
     let image = @layers::layers::Image::new(image_data as @layers::layers::ImageData);
     let image_layer = @layers::layers::ImageLayer(image);
     let original_layer_transform = image_layer.common.transform;
@@ -130,7 +130,8 @@ fn mainloop(mode: Mode, po: comm::Port<Msg>, dom_event_chan: pipes::SharedChan<E
                     let height = surfaces.front.layer_buffer.size.height as uint;
 
                     let image_data = @CairoSurfaceImageData {
-                        cairo_surface: surfaces.front.layer_buffer.cairo_surface.clone()
+                        cairo_surface: surfaces.front.layer_buffer.cairo_surface.clone(),
+                        size: Size2D(width, height)
                     };
                     let image = @layers::layers::Image::new(
                         image_data as @layers::layers::ImageData);
@@ -217,7 +218,8 @@ fn lend_surface(surfaces: &SurfaceSet, receiver: pipes::Chan<LayerBuffer>) {
     let layer_buffer = LayerBuffer {
         cairo_surface: surfaces.front.layer_buffer.cairo_surface.clone(),
         draw_target: azure_hl::clone_mutable_draw_target(draw_target_ref),
-        size: copy surfaces.front.layer_buffer.size
+        size: copy surfaces.front.layer_buffer.size,
+        stride: surfaces.front.layer_buffer.stride
     };
     #debug("osmain: lending surface %?", layer_buffer);
     receiver.send(move layer_buffer);
@@ -256,7 +258,8 @@ fn Surface() -> Surface {
     let layer_buffer = LayerBuffer {
         cairo_surface: move cairo_surface,
         draw_target: move draw_target,
-        size: Size2D(800u, 600u)
+        size: Size2D(800u, 600u),
+        stride: 800
     };
     Surface { layer_buffer: move layer_buffer, have: true }
 }