Auto merge of #997 - JerryShih:gl-texture-rect-support, r=kvark

GL_TEXTURE_RECTANGLE texture target support

@glennw @kvark @nical @sotaroikeda
The hardware video decoder in mac platform is usually decoding the video content into MacIOSurface. The MacIOSurface could just map to  an GL_TEXTURE_RECTANGLE gl texture without any uploading. That's good for video playing.
These patches try to add a new type of external gl rect image and its corresponding shader.

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webrender/res/ps_image.fs.glsl

@@ -24,12 +24,15 @@ void main(void) {
     // account the spacing in between tiles. We only paint if our fragment does
     // not fall into that spacing.
     vec2 position_in_tile = mod(relative_pos_in_rect, vStretchSize + vTileSpacing);
-    // We clamp the texture coordinates to the half-pixel offset from the borders
-    // in order to avoid sampling outside of the texture area.
     vec2 st = vTextureOffset + ((position_in_tile / vStretchSize) * vTextureSize);
     st = clamp(st, vStRect.xy, vStRect.zw);
 
     alpha = alpha * float(all(bvec2(step(position_in_tile, vStretchSize))));
 
+#ifdef WR_FEATURE_TEXTURE_RECT
+    // textureLod doesn't support sampler2DRect. Use texture() instead.
+    oFragColor = vec4(alpha) * texture(sColor0, st);
+#else
     oFragColor = vec4(alpha) * textureLod(sColor0, st, 0.0);
+#endif
 }

webrender/res/ps_image.glsl

@@ -2,10 +2,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+// If this is in WR_FEATURE_TEXTURE_RECT mode, the rect and size use non-normalized
+// texture coordinates. Otherwise, it uses normalized texture coordinates. Please
+// check GL_TEXTURE_RECTANGLE.
 flat varying vec2 vTextureOffset; // Offset of this image into the texture atlas.
 flat varying vec2 vTextureSize;   // Size of the image in the texture atlas.
 flat varying vec2 vTileSpacing;   // Amount of space between tiled instances of this image.
-flat varying vec4 vStRect;     	  // Rectangle of valid texture rect, in st-space.
+flat varying vec4 vStRect;        // Rectangle of valid texture rect.
 
 #ifdef WR_FEATURE_TRANSFORM
 varying vec3 vLocalPos;

webrender/res/ps_image.vs.glsl

@@ -27,16 +27,28 @@ void main(void) {
 
     write_clip(vi.screen_pos, prim.clip_area);
 
+    vTileSpacing = image.stretch_size_and_tile_spacing.zw;
+    vStretchSize = image.stretch_size_and_tile_spacing.xy;
+
+    // If this is in WR_FEATURE_TEXTURE_RECT mode, the rect and size use
+    // non-normalized texture coordinates.
+#ifdef WR_FEATURE_TEXTURE_RECT
+    vec2 texture_size_normalization_factor = vec2(1, 1);
+#else
+    vec2 texture_size_normalization_factor = vec2(textureSize(sColor0, 0));
+#endif
+
     // vUv will contain how many times this image has wrapped around the image size.
-    vec2 texture_size = vec2(textureSize(sColor0, 0));
-    vec2 st0 = res.uv_rect.xy / texture_size;
-    vec2 st1 = res.uv_rect.zw / texture_size;
+    vec2 st0 = res.uv_rect.xy / texture_size_normalization_factor;
+    vec2 st1 = res.uv_rect.zw / texture_size_normalization_factor;
 
     vTextureSize = st1 - st0;
     vTextureOffset = st0;
     vTileSpacing = image.stretch_size_and_tile_spacing.zw;
     vStretchSize = image.stretch_size_and_tile_spacing.xy;
 
-    vec2 half_texel = vec2(0.5) / texture_size;
+    // We clamp the texture coordinates to the half-pixel offset from the borders
+    // in order to avoid sampling outside of the texture area.
+    vec2 half_texel = vec2(0.5) / texture_size_normalization_factor;
     vStRect = vec4(min(st0, st1) + half_texel, max(st0, st1) - half_texel);
 }

webrender/res/shared.glsl

@@ -33,9 +33,15 @@
 //======================================================================================
 // Shared shader uniforms
 //======================================================================================
+#ifndef WR_FEATURE_TEXTURE_RECT
 uniform sampler2D sColor0;
 uniform sampler2D sColor1;
 uniform sampler2D sColor2;
+#else
+uniform sampler2DRect sColor0;
+uniform sampler2DRect sColor1;
+uniform sampler2DRect sColor2;
+#endif
 uniform sampler2D sDither;
 uniform sampler2D sMask;
 

webrender/src/device.rs

@@ -51,6 +51,17 @@ pub enum DepthFunction {
 pub enum TextureTarget {
     Default,
     Array,
+    Rect,
+}
+
+impl TextureTarget {
+    pub fn to_gl_target(&self) -> gl::GLuint {
+        match *self {
+            TextureTarget::Default => gl::TEXTURE_2D,
+            TextureTarget::Array => gl::TEXTURE_2D_ARRAY,
+            TextureTarget::Rect => gl::TEXTURE_RECTANGLE,
+        }
+    }
 }
 
 #[derive(Copy, Clone, Debug, PartialEq)]
@@ -304,10 +315,10 @@ impl TextureId {
         gl.bind_texture(self.target, self.name);
     }
 
-    pub fn new(name: gl::GLuint) -> TextureId {
+    pub fn new(name: gl::GLuint, texture_target: TextureTarget) -> TextureId {
         TextureId {
             name: name,
-            target: gl::TEXTURE_2D,
+            target: texture_target.to_gl_target(),
         }
     }
 
@@ -1090,15 +1101,10 @@ impl Device {
         let id_list = self.gl.gen_textures(count);
         let mut texture_ids = Vec::new();
 
-        let target = match target {
-            TextureTarget::Default => gl::TEXTURE_2D,
-            TextureTarget::Array => gl::TEXTURE_2D_ARRAY,
-        };
-
         for id in id_list {
             let texture_id = TextureId {
                 name: id,
-                target: target,
+                target: target.to_gl_target(),
             };
 
             let texture = Texture {

webrender/src/internal_types.rs

@@ -17,7 +17,7 @@ use tiling;
 use renderer::BlendMode;
 use webrender_traits::{Epoch, ColorF, PipelineId};
 use webrender_traits::{ImageFormat, NativeFontHandle};
-use webrender_traits::{ExternalImageId, ScrollLayerId};
+use webrender_traits::{ExternalImageData, ExternalImageId, ScrollLayerId};
 use webrender_traits::{ImageData};
 use webrender_traits::{DeviceUintRect};
 
@@ -43,7 +43,7 @@ pub struct CacheTextureId(pub usize);
 pub enum SourceTexture {
     Invalid,
     TextureCache(CacheTextureId),
-    External(ExternalImageId),
+    External(ExternalImageData),
     #[cfg_attr(not(feature = "webgl"), allow(dead_code))]
     /// This is actually a gl::GLuint, with the shared texture id between the
     /// main context and the WebGL context.

webrender/src/prim_store.rs

@@ -868,8 +868,8 @@ impl PrimitiveStore {
 
         // Check if an external image that needs to be resolved
         // by the render thread.
-        match image_properties.external_id {
-            Some(external_id) => {
+        match image_properties.external_image {
+            Some(external_image) => {
                 // This is an external texture - we will add it to
                 // the deferred resolves list to be patched by
                 // the render thread...
@@ -878,7 +878,7 @@ impl PrimitiveStore {
                     resource_address: image_uv_address,
                 });
 
-                (SourceTexture::External(external_id), None)
+                (SourceTexture::External(external_image), None)
             }
             None => {
                 let cache_item = resource_cache.get_cached_image(image_key, image_rendering, tile_offset);

webrender/src/renderer.rs

@@ -49,7 +49,7 @@ use thread_profiler::{register_thread_with_profiler, write_profile};
 use util::TransformedRectKind;
 use webgl_types::GLContextHandleWrapper;
 use webrender_traits::{ColorF, Epoch, PipelineId, RenderNotifier, RenderDispatcher};
-use webrender_traits::{ExternalImageId, ImageData, ImageFormat, RenderApiSender};
+use webrender_traits::{ExternalImageId, ExternalImageType, ImageData, ImageFormat, RenderApiSender};
 use webrender_traits::{DeviceIntRect, DevicePoint, DeviceIntPoint, DeviceIntSize, DeviceUintSize};
 use webrender_traits::{ImageDescriptor, BlobImageRenderer};
 use webrender_traits::channel;
@@ -65,6 +65,7 @@ const GPU_TAG_INIT: GpuProfileTag = GpuProfileTag { label: "Init", color: debug_
 const GPU_TAG_SETUP_TARGET: GpuProfileTag = GpuProfileTag { label: "Target", color: debug_colors::SLATEGREY };
 const GPU_TAG_PRIM_RECT: GpuProfileTag = GpuProfileTag { label: "Rect", color: debug_colors::RED };
 const GPU_TAG_PRIM_IMAGE: GpuProfileTag = GpuProfileTag { label: "Image", color: debug_colors::GREEN };
+const GPU_TAG_PRIM_IMAGE_RECT: GpuProfileTag = GpuProfileTag { label: "ImageRect", color: debug_colors::GREENYELLOW };
 const GPU_TAG_PRIM_YUV_IMAGE: GpuProfileTag = GpuProfileTag { label: "YuvImage", color: debug_colors::DARKGREEN };
 const GPU_TAG_PRIM_BLEND: GpuProfileTag = GpuProfileTag { label: "Blend", color: debug_colors::LIGHTBLUE };
 const GPU_TAG_PRIM_HW_COMPOSITE: GpuProfileTag = GpuProfileTag { label: "HwComposite", color: debug_colors::DODGERBLUE };
@@ -223,6 +224,7 @@ pub type GradientDataStore = GpuStore<GradientData, GradientDataTextureLayout>;
 const TRANSFORM_FEATURE: &'static str = "TRANSFORM";
 const SUBPIXEL_AA_FEATURE: &'static str = "SUBPIXEL_AA";
 const CLIP_FEATURE: &'static str = "CLIP";
+const TEXTURE_RECT_FEATURE: &'static str = "TEXTURE_RECT";
 
 enum ShaderKind {
     Primitive,
@@ -465,6 +467,7 @@ pub struct Renderer {
     ps_text_run: PrimitiveShader,
     ps_text_run_subpixel: PrimitiveShader,
     ps_image: PrimitiveShader,
+    ps_image_rect: PrimitiveShader,
     ps_yuv_image: PrimitiveShader,
     ps_border: PrimitiveShader,
     ps_gradient: PrimitiveShader,
@@ -670,6 +673,13 @@ impl Renderer {
                                  options.precache_shaders)
         };
 
+        let ps_image_rect = try!{
+            PrimitiveShader::new("ps_image",
+                                 &mut device,
+                                 &[ TEXTURE_RECT_FEATURE ],
+                                 options.precache_shaders)
+        };
+
         let ps_yuv_image = try!{
             PrimitiveShader::new("ps_yuv_image",
                                  &mut device,
@@ -912,6 +922,7 @@ impl Renderer {
             ps_text_run: ps_text_run,
             ps_text_run_subpixel: ps_text_run_subpixel,
             ps_image: ps_image,
+            ps_image_rect: ps_image_rect,
             ps_yuv_image: ps_yuv_image,
             ps_border: ps_border,
             ps_box_shadow: ps_box_shadow,
@@ -1039,10 +1050,10 @@ impl Renderer {
     fn resolve_source_texture(&mut self, texture_id: &SourceTexture) -> TextureId {
         match *texture_id {
             SourceTexture::Invalid => TextureId::invalid(),
-            SourceTexture::WebGL(id) => TextureId::new(id),
-            SourceTexture::External(ref key) => {
+            SourceTexture::WebGL(id) => TextureId::new(id, TextureTarget::Default),
+            SourceTexture::External(external_image) => {
                 *self.external_images
-                     .get(key)
+                     .get(&external_image.id)
                      .expect("BUG: External image should be resolved by now!")
             }
             SourceTexture::TextureCache(index) => {
@@ -1193,24 +1204,31 @@ impl Renderer {
                                                              mode,
                                                              Some(raw.as_slice()));
                                 }
-                                ImageData::ExternalBuffer(id) => {
-                                    let handler = self.external_image_handler
-                                                      .as_mut()
-                                                      .expect("Found external image, but no handler set!");
-
-                                    match handler.lock(id).source {
-                                        ExternalImageSource::RawData(raw) => {
-                                            self.device.init_texture(texture_id,
-                                                                     width,
-                                                                     height,
-                                                                     format,
-                                                                     filter,
-                                                                     mode,
-                                                                     Some(raw));
+                                ImageData::External(ext_image) => {
+                                    match ext_image.image_type {
+                                        ExternalImageType::ExternalBuffer => {
+                                            let handler = self.external_image_handler
+                                                              .as_mut()
+                                                              .expect("Found external image, but no handler set!");
+
+                                            match handler.lock(ext_image.id).source {
+                                                ExternalImageSource::RawData(raw) => {
+                                                    self.device.init_texture(texture_id,
+                                                                             width,
+                                                                             height,
+                                                                             format,
+                                                                             filter,
+                                                                             mode,
+                                                                             Some(raw));
+                                                }
+                                                _ => panic!("No external buffer found"),
+                                            };
+                                            handler.unlock(ext_image.id);
                                         }
-                                        _ => panic!("No external buffer found"),
-                                    };
-                                    handler.unlock(id);
+                                        _ => {
+                                            panic!("External texture handle should not use TextureUpdateOp::Create.");
+                                        }
+                                    }
                                 }
                                 _ => {
                                     panic!("No suitable image buffer for TextureUpdateOp::Create.");
@@ -1339,6 +1357,10 @@ impl Renderer {
                         let shader = self.ps_image.get(&mut self.device, transform_kind);
                         (GPU_TAG_PRIM_IMAGE, shader)
                     }
+                    AlphaBatchKind::ImageRect => {
+                        let shader = self.ps_image_rect.get(&mut self.device, transform_kind);
+                        (GPU_TAG_PRIM_IMAGE_RECT, shader)
+                    }
                     AlphaBatchKind::YuvImage => {
                         let shader = self.ps_yuv_image.get(&mut self.device, transform_kind);
                         (GPU_TAG_PRIM_YUV_IMAGE, shader)
@@ -1665,16 +1687,24 @@ impl Renderer {
             for deferred_resolve in &frame.deferred_resolves {
                 GpuMarker::fire(self.device.gl(), "deferred resolve");
                 let props = &deferred_resolve.image_properties;
-                let external_id = props.external_id
-                                       .expect("BUG: Deferred resolves must be external images!");
-                let image = handler.lock(external_id);
+                let ext_image = props.external_image
+                                     .expect("BUG: Deferred resolves must be external images!");
+                let image = handler.lock(ext_image.id);
+                let texture_target = match ext_image.image_type {
+                    ExternalImageType::Texture2DHandle => TextureTarget::Default,
+                    ExternalImageType::TextureRectHandle => TextureTarget::Rect,
+                    _ => {
+                        panic!("{:?} is not a suitable image type in update_deferred_resolves().",
+                            ext_image.image_type);
+                    }
+                };
 
                 let texture_id = match image.source {
-                    ExternalImageSource::NativeTexture(texture_id) => TextureId::new(texture_id),
+                    ExternalImageSource::NativeTexture(texture_id) => TextureId::new(texture_id, texture_target),
                     _ => panic!("No native texture found."),
                 };
 
-                self.external_images.insert(external_id, texture_id);
+                self.external_images.insert(ext_image.id, texture_id);
                 let resource_rect_index = deferred_resolve.resource_address.0 as usize;
                 let resource_rect = &mut frame.gpu_resource_rects[resource_rect_index];
                 resource_rect.uv0 = DevicePoint::new(image.u0, image.v0);