Auto merge of #21850 - servo:webgl, r=jdm

Don't use an intermediate PNG buffer in HTMLCanvasElement::ToDataURL

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8 files changed, 60 insertions, 49 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 2c395094e7f..a3c4c7814ea 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -261,7 +261,13 @@ unsafe impl<T: JSTraceable> JSTraceable for VecDeque<T> {
     }
 }
 
-unsafe impl<T: JSTraceable> JSTraceable for (T, T, T, T) {
+unsafe impl<A, B, C, D> JSTraceable for (A, B, C, D)
+where
+    A: JSTraceable,
+    B: JSTraceable,
+    C: JSTraceable,
+    D: JSTraceable,
+{
     unsafe fn trace(&self, trc: *mut JSTracer) {
         self.0.trace(trc);
         self.1.trace(trc);
@@ -616,6 +622,13 @@ unsafe impl<U> JSTraceable for TypedSize2D<f32, U> {
     }
 }
 
+unsafe impl<U> JSTraceable for TypedSize2D<u32, U> {
+    #[inline]
+    unsafe fn trace(&self, _trc: *mut JSTracer) {
+        // Do nothing
+    }
+}
+
 unsafe impl JSTraceable for StyleLocked<FontFaceRule> {
     unsafe fn trace(&self, _trc: *mut JSTracer) {
         // Do nothing.
diff --git a/components/script/dom/canvaspattern.rs b/components/script/dom/canvaspattern.rs
index ced7a6bb11b..bcc6e35f5f5 100644
--- a/components/script/dom/canvaspattern.rs
+++ b/components/script/dom/canvaspattern.rs
@@ -16,7 +16,7 @@ use euclid::Size2D;
 pub struct CanvasPattern {
     reflector_: Reflector,
     surface_data: Vec<u8>,
-    surface_size: Size2D<i32>,
+    surface_size: Size2D<u32>,
     repeat_x: bool,
     repeat_y: bool,
     origin_clean: bool,
@@ -25,7 +25,7 @@ pub struct CanvasPattern {
 impl CanvasPattern {
     fn new_inherited(
         surface_data: Vec<u8>,
-        surface_size: Size2D<i32>,
+        surface_size: Size2D<u32>,
         repeat: RepetitionStyle,
         origin_clean: bool,
     ) -> CanvasPattern {
@@ -39,7 +39,7 @@ impl CanvasPattern {
         CanvasPattern {
             reflector_: Reflector::new(),
             surface_data: surface_data,
-            surface_size: surface_size,
+            surface_size,
             repeat_x: x,
             repeat_y: y,
             origin_clean: origin_clean,
@@ -48,7 +48,7 @@ impl CanvasPattern {
     pub fn new(
         global: &GlobalScope,
         surface_data: Vec<u8>,
-        surface_size: Size2D<i32>,
+        surface_size: Size2D<u32>,
         repeat: RepetitionStyle,
         origin_clean: bool,
     ) -> DomRoot<CanvasPattern> {
diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index e3ca01c311e..2b364c3702d 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -128,7 +128,7 @@ impl CanvasRenderingContext2D {
         canvas: Option<&HTMLCanvasElement>,
         image_cache: Arc<ImageCache>,
         base_url: ServoUrl,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
     ) -> CanvasRenderingContext2D {
         debug!("Creating new canvas rendering context.");
         let (sender, receiver) =
@@ -157,7 +157,7 @@ impl CanvasRenderingContext2D {
     pub fn new(
         global: &GlobalScope,
         canvas: &HTMLCanvasElement,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
     ) -> DomRoot<CanvasRenderingContext2D> {
         let window = window_from_node(canvas);
         let image_cache = window.image_cache();
@@ -173,7 +173,7 @@ impl CanvasRenderingContext2D {
     }
 
     // https://html.spec.whatwg.org/multipage/#concept-canvas-set-bitmap-dimensions
-    pub fn set_bitmap_dimensions(&self, size: Size2D<i32>) {
+    pub fn set_bitmap_dimensions(&self, size: Size2D<u32>) {
         self.reset_to_initial_state();
         self.ipc_renderer
             .send(CanvasMsg::Recreate(size, self.get_canvas_id()))
@@ -456,7 +456,7 @@ impl CanvasRenderingContext2D {
         Ok(())
     }
 
-    fn fetch_image_data(&self, url: ServoUrl) -> Option<(Vec<u8>, Size2D<i32>)> {
+    fn fetch_image_data(&self, url: ServoUrl) -> Option<(Vec<u8>, Size2D<u32>)> {
         let img = match self.request_image_from_cache(url) {
             ImageResponse::Loaded(img, _) => img,
             ImageResponse::PlaceholderLoaded(_, _) |
@@ -466,7 +466,7 @@ impl CanvasRenderingContext2D {
             },
         };
 
-        let image_size = Size2D::new(img.width as i32, img.height as i32);
+        let image_size = Size2D::new(img.width, img.height);
         let image_data = match img.format {
             PixelFormat::BGRA8 => img.bytes.to_vec(),
             PixelFormat::K8 => panic!("K8 color type not supported"),
diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 00b04db7ee8..09114a95d0a 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -98,8 +98,8 @@ impl HTMLCanvasElement {
         }
     }
 
-    pub fn get_size(&self) -> Size2D<i32> {
-        Size2D::new(self.Width() as i32, self.Height() as i32)
+    pub fn get_size(&self) -> Size2D<u32> {
+        Size2D::new(self.Width(), self.Height())
     }
 
     pub fn origin_is_clean(&self) -> bool {
@@ -277,7 +277,7 @@ impl HTMLCanvasElement {
         self.Height() != 0 && self.Width() != 0
     }
 
-    pub fn fetch_all_data(&self) -> Option<(Vec<u8>, Size2D<i32>)> {
+    pub fn fetch_all_data(&self) -> Option<(Vec<u8>, Size2D<u32>)> {
         let size = self.get_size();
 
         if size.width == 0 || size.height == 0 {
@@ -383,12 +383,11 @@ impl HTMLCanvasElementMethods for HTMLCanvasElement {
                     None => return Ok(USVString("data:,".into())),
                 }
             },
-            Some(CanvasContext::WebGL2(ref context)) => match context
-                .base_context()
-                .get_image_data(self.Width(), self.Height())
-            {
-                Some(data) => data,
-                None => return Ok(USVString("data:,".into())),
+            Some(CanvasContext::WebGL2(ref context)) => {
+                match context.base_context().get_image_data(self.Width(), self.Height()) {
+                    Some(data) => data,
+                    None => return Ok(USVString("data:,".into())),
+                }
             },
             None => {
                 // Each pixel is fully-transparent black.
@@ -396,19 +395,16 @@ impl HTMLCanvasElementMethods for HTMLCanvasElement {
             },
         };
 
-        // Only handle image/png for now.
-        let mime_type = "image/png";
-
-        let mut encoded = Vec::new();
-        {
-            let encoder: PNGEncoder<&mut Vec<u8>> = PNGEncoder::new(&mut encoded);
-            encoder
-                .encode(&raw_data, self.Width(), self.Height(), ColorType::RGBA(8))
-                .unwrap();
-        }
-
-        let encoded = base64::encode(&encoded);
-        Ok(USVString(format!("data:{};base64,{}", mime_type, encoded)))
+        // FIXME: Only handle image/png for now.
+        let mut png = Vec::new();
+        PNGEncoder::new(&mut png)
+            .encode(&raw_data, self.Width(), self.Height(), ColorType::RGBA(8))
+            .unwrap();
+        let mut url = "data:image/png;base64,".to_owned();
+        // FIXME(nox): Should this use base64::URL_SAFE?
+        // FIXME(nox): https://github.com/alicemaz/rust-base64/pull/56
+        base64::encode_config_buf(&png, base64::STANDARD, &mut url);
+        Ok(USVString(url))
     }
 }
 
diff --git a/components/script/dom/imagedata.rs b/components/script/dom/imagedata.rs
index d37e0092ba4..ea65d533ffe 100644
--- a/components/script/dom/imagedata.rs
+++ b/components/script/dom/imagedata.rs
@@ -149,8 +149,8 @@ impl ImageData {
         }
     }
 
-    pub fn get_size(&self) -> Size2D<i32> {
-        Size2D::new(self.Width() as i32, self.Height() as i32)
+    pub fn get_size(&self) -> Size2D<u32> {
+        Size2D::new(self.Width(), self.Height())
     }
 }
 
diff --git a/components/script/dom/paintrenderingcontext2d.rs b/components/script/dom/paintrenderingcontext2d.rs
index 43124e30c76..1389dddcf3a 100644
--- a/components/script/dom/paintrenderingcontext2d.rs
+++ b/components/script/dom/paintrenderingcontext2d.rs
@@ -85,8 +85,7 @@ impl PaintRenderingContext2D {
     ) {
         let size = size * device_pixel_ratio;
         self.device_pixel_ratio.set(device_pixel_ratio);
-        self.context
-            .set_bitmap_dimensions(size.to_untyped().to_i32());
+        self.context.set_bitmap_dimensions(size.to_untyped().to_u32());
         self.scale_by_device_pixel_ratio();
     }
 
diff --git a/components/script/dom/webgl2renderingcontext.rs b/components/script/dom/webgl2renderingcontext.rs
index a674cd719a6..ec839bf3fbf 100644
--- a/components/script/dom/webgl2renderingcontext.rs
+++ b/components/script/dom/webgl2renderingcontext.rs
@@ -49,7 +49,7 @@ impl WebGL2RenderingContext {
     fn new_inherited(
         window: &Window,
         canvas: &HTMLCanvasElement,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
         attrs: GLContextAttributes,
     ) -> Option<WebGL2RenderingContext> {
         let base = WebGLRenderingContext::new(window, canvas, WebGLVersion::WebGL2, size, attrs)?;
@@ -63,7 +63,7 @@ impl WebGL2RenderingContext {
     pub fn new(
         window: &Window,
         canvas: &HTMLCanvasElement,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
         attrs: GLContextAttributes,
     ) -> Option<DomRoot<WebGL2RenderingContext>> {
         WebGL2RenderingContext::new_inherited(window, canvas, size, attrs).map(|ctx| {
@@ -73,7 +73,7 @@ impl WebGL2RenderingContext {
 }
 
 impl WebGL2RenderingContext {
-    pub fn recreate(&self, size: Size2D<i32>) {
+    pub fn recreate(&self, size: Size2D<u32>) {
         self.base.recreate(size)
     }
 
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 754637ad52b..7972201b9ce 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -157,7 +157,7 @@ pub struct WebGLRenderingContext {
     #[ignore_malloc_size_of = "Because it's small"]
     current_vertex_attrib_0: Cell<(f32, f32, f32, f32)>,
     #[ignore_malloc_size_of = "Because it's small"]
-    current_scissor: Cell<(i32, i32, i32, i32)>,
+    current_scissor: Cell<(i32, i32, u32, u32)>,
     #[ignore_malloc_size_of = "Because it's small"]
     current_clear_color: Cell<(f32, f32, f32, f32)>,
     extension_manager: WebGLExtensions,
@@ -172,7 +172,7 @@ impl WebGLRenderingContext {
         window: &Window,
         canvas: &HTMLCanvasElement,
         webgl_version: WebGLVersion,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
         attrs: GLContextAttributes,
     ) -> Result<WebGLRenderingContext, String> {
         if let Some(true) = PREFS
@@ -229,7 +229,7 @@ impl WebGLRenderingContext {
         window: &Window,
         canvas: &HTMLCanvasElement,
         webgl_version: WebGLVersion,
-        size: Size2D<i32>,
+        size: Size2D<u32>,
         attrs: GLContextAttributes,
     ) -> Option<DomRoot<WebGLRenderingContext>> {
         match WebGLRenderingContext::new_inherited(window, canvas, webgl_version, size, attrs) {
@@ -266,7 +266,7 @@ impl WebGLRenderingContext {
         })
     }
 
-    pub fn recreate(&self, size: Size2D<i32>) {
+    pub fn recreate(&self, size: Size2D<u32>) {
         let (sender, receiver) = webgl_channel().unwrap();
         self.webgl_sender.send_resize(size, sender).unwrap();
 
@@ -517,7 +517,7 @@ impl WebGLRenderingContext {
     fn get_image_pixels(
         &self,
         source: TexImageSource,
-    ) -> Fallible<Option<(Vec<u8>, Size2D<i32>, bool)>> {
+    ) -> Fallible<Option<(Vec<u8>, Size2D<u32>, bool)>> {
         Ok(Some(match source {
             TexImageSource::ImageData(image_data) => {
                 (image_data.get_data_array(), image_data.get_size(), false)
@@ -542,7 +542,7 @@ impl WebGLRenderingContext {
                     ImageResponse::MetadataLoaded(_) => return Ok(None),
                 };
 
-                let size = Size2D::new(img.width as i32, img.height as i32);
+                let size = Size2D::new(img.width, img.height);
 
                 // For now Servo's images are all stored as BGRA8 internally.
                 let mut data = match img.format {
@@ -2940,6 +2940,9 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             return self.webgl_error(InvalidValue);
         }
 
+        let width = width as u32;
+        let height = height as u32;
+
         self.current_scissor.set((x, y, width, height));
         self.send_command(WebGLCommand::Scissor(x, y, width, height));
     }
@@ -3791,8 +3794,8 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             target,
             level,
             internal_format,
-            size.width,
-            size.height,
+            size.width as i32,
+            size.height as i32,
             0,
             format,
             data_type,
@@ -4003,8 +4006,8 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
             target,
             level,
             format,
-            size.width,
-            size.height,
+            size.width as i32,
+            size.height as i32,
             0,
             format,
             data_type,