Auto merge of #554 - glennw:ext, r=pcwalton

Introduce SourceTexture, an abstraction for location of source textures.

This allows the backend thread to work with textures that have
been allocation by the texture cache, via webgl or an external
source transparently. The native texture ID is resolved by the
rendering thread as requited.

Specifically:

* Add SourceTexture, an abstraction for the location of a source texture.
* Add CacheTextureID, an ID for a texture cache managed texture.
    * This removes the need to allocate a pool of textures up front.
* Remove unused batch.rs file.
* Remove the concept of "raw textures" from device.rs
    * The native texture ID is stored inside the SourceTexture enum now.
* Remove some unused functions in device.rs.

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Author: bors-servo

webrender/src/batch.rs

@@ -735,7 +735,6 @@ pub struct Device {
     // resources
     resource_path: PathBuf,
     textures: HashMap<TextureId, Texture, BuildHasherDefault<FnvHasher>>,
-    raw_textures: HashMap<TextureId, (u32, u32, u32, u32), BuildHasherDefault<FnvHasher>>,
     programs: HashMap<ProgramId, Program, BuildHasherDefault<FnvHasher>>,
     vaos: HashMap<VAOId, VAO, BuildHasherDefault<FnvHasher>>,
 
@@ -778,7 +777,6 @@ impl Device {
             default_fbo: 0,
 
             textures: HashMap::with_hasher(Default::default()),
-            raw_textures: HashMap::with_hasher(Default::default()),
             programs: HashMap::with_hasher(Default::default()),
             vaos: HashMap::with_hasher(Default::default()),
 
@@ -946,33 +944,8 @@ impl Device {
     }
 
     pub fn get_texture_dimensions(&self, texture_id: TextureId) -> (u32, u32) {
-        if let Some(texture) = self.textures.get(&texture_id) {
-            (texture.width, texture.height)
-        } else {
-            let dimensions = self.raw_textures.get(&texture_id).unwrap();
-            (dimensions.2, dimensions.3)
-        }
-    }
-
-    pub fn texture_has_alpha(&self, texture_id: TextureId) -> bool {
-        if let Some(texture) = self.textures.get(&texture_id) {
-            texture.format == ImageFormat::RGBA8
-        } else {
-            true
-        }
-    }
-
-    pub fn update_raw_texture(&mut self,
-                              texture_id: TextureId,
-                              x0: u32,
-                              y0: u32,
-                              width: u32,
-                              height: u32) {
-        self.raw_textures.insert(texture_id, (x0, y0, width, height));
-    }
-
-    pub fn remove_raw_texture(&mut self, texture_id: TextureId) {
-        self.raw_textures.remove(&texture_id);
+        let texture = &self.textures[&texture_id];
+        (texture.width, texture.height)
     }
 
     fn set_texture_parameters(&mut self, target: gl::GLuint, filter: TextureFilter) {
@@ -1526,25 +1499,6 @@ impl Device {
         }
     }
 
-    pub fn read_framebuffer_rect(&mut self,
-                                 texture_id: TextureId,
-                                 dest_x: i32,
-                                 dest_y: i32,
-                                 src_x: i32,
-                                 src_y: i32,
-                                 width: i32,
-                                 height: i32) {
-        self.bind_texture(DEFAULT_TEXTURE, texture_id);
-        gl::copy_tex_sub_image_2d(texture_id.target,
-                                  0,
-                                  dest_x,
-                                  dest_y,
-                                  src_x as gl::GLint,
-                                  src_y as gl::GLint,
-                                  width as gl::GLint,
-                                  height as gl::GLint);
-    }
-
     fn clear_vertex_array(&mut self) {
         debug_assert!(self.inside_frame);
         gl::bind_vertex_array(0);

webrender/src/device.rs

@@ -3,8 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use app_units::Au;
-use device::{TextureId, TextureFilter};
-use euclid::{Point2D, Rect, Size2D, TypedRect, TypedPoint2D, TypedSize2D, Length, UnknownUnit};
+use device::TextureFilter;
+use euclid::{Size2D, TypedRect, TypedPoint2D, TypedSize2D, Length, UnknownUnit};
 use fnv::FnvHasher;
 use offscreen_gl_context::{NativeGLContext, NativeGLContextHandle};
 use offscreen_gl_context::{GLContext, NativeGLContextMethods, GLContextDispatcher};
@@ -14,14 +14,42 @@ use profiler::BackendProfileCounters;
 use std::collections::{HashMap, HashSet};
 use std::f32;
 use std::hash::BuildHasherDefault;
-use std::i32;
+use std::{i32, usize};
 use std::path::PathBuf;
 use std::sync::Arc;
 use tiling;
 use webrender_traits::{Epoch, ColorF, PipelineId};
 use webrender_traits::{ImageFormat, MixBlendMode, NativeFontHandle};
 use webrender_traits::{ScrollLayerId, WebGLCommand};
 
+// An ID for a texture that is owned by the
+// texture cache module. This can include atlases
+// or standalone textures allocated via the
+// texture cache (e.g. if an image is too large
+// to be added to an atlas). The texture cache
+// manages the allocation and freeing of these
+// IDs, and the rendering thread maintains a
+// map from cache texture ID to native texture.
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
+pub struct CacheTextureId(pub usize);
+
+// Represents the source for a texture.
+// These are passed from throughout the
+// pipeline until they reach the rendering
+// thread, where they are resolved to a
+// native texture ID.
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
+pub enum SourceTexture {
+    Invalid,
+    TextureCache(CacheTextureId),
+    WebGL(u32),                         // Is actually a gl::GLuint
+
+    // TODO(gw): Implement external image support via callback
+    //External(i32),
+}
+
 pub enum GLContextHandleWrapper {
     Native(NativeGLContextHandle),
     OSMesa(OSMesaContextHandle),
@@ -194,15 +222,15 @@ impl TextureSampler {
 /// Textures that are not used by the batch are equal to TextureId::invalid().
 #[derive(Copy, Clone, Debug)]
 pub struct BatchTextures {
-    pub colors: [TextureId; 3],
-    pub mask: TextureId,
+    pub colors: [SourceTexture; 3],
+    pub mask: SourceTexture,
 }
 
 impl BatchTextures {
     pub fn no_texture() -> Self {
         BatchTextures {
-            colors: [TextureId::invalid(); 3],
-            mask: TextureId::invalid(),
+            colors: [SourceTexture::Invalid; 3],
+            mask: SourceTexture::Invalid,
         }
     }
 }
@@ -332,28 +360,14 @@ pub enum RenderTargetMode {
     LayerRenderTarget(i32),      // Number of texture layers
 }
 
-#[derive(Debug)]
-pub enum TextureUpdateDetails {
-    Raw,
-    Blit(Vec<u8>, Option<u32>),
-}
-
-#[derive(Clone, Copy, Debug)]
-pub struct TextureImage {
-    pub texture_id: TextureId,
-    pub texel_uv: Rect<f32>,
-    pub pixel_uv: Point2D<u32>,
-}
-
 pub enum TextureUpdateOp {
     Create(u32, u32, ImageFormat, TextureFilter, RenderTargetMode, Option<Vec<u8>>),
-    Update(u32, u32, u32, u32, TextureUpdateDetails),
+    Update(u32, u32, u32, u32, Vec<u8>, Option<u32>),
     Grow(u32, u32, ImageFormat, TextureFilter, RenderTargetMode),
-    Remove
 }
 
 pub struct TextureUpdate {
-    pub id: TextureId,
+    pub id: CacheTextureId,
     pub op: TextureUpdateOp,
 }
 

webrender/src/internal_types.rs

@@ -3,10 +3,9 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use app_units::Au;
-use device::TextureId;
 use euclid::{Point2D, Matrix4D, Rect, Size2D};
 use gpu_store::{GpuStore, GpuStoreAddress};
-use internal_types::{device_pixel, DeviceRect, DeviceSize};
+use internal_types::{device_pixel, DeviceRect, DeviceSize, SourceTexture};
 use resource_cache::ResourceCache;
 use std::mem;
 use std::usize;
@@ -63,7 +62,7 @@ pub enum PrimitiveClipSource {
 #[derive(Debug)]
 pub struct PrimitiveMetadata {
     pub is_opaque: bool,
-    pub mask_texture_id: TextureId,
+    pub mask_texture_id: SourceTexture,
     pub clip_index: Option<GpuStoreAddress>,
     pub clip_source: Box<PrimitiveClipSource>,
     pub prim_kind: PrimitiveKind,
@@ -96,7 +95,7 @@ pub enum ImagePrimitiveKind {
 #[derive(Debug)]
 pub struct ImagePrimitiveCpu {
     pub kind: ImagePrimitiveKind,
-    pub color_texture_id: TextureId,
+    pub color_texture_id: SourceTexture,
 }
 
 #[derive(Debug, Clone)]
@@ -189,7 +188,7 @@ pub struct TextRunPrimitiveCpu {
     pub cache_dirty: bool,
     // TODO(gw): Maybe make this an Arc for sharing with resource cache
     pub glyph_indices: Vec<u32>,
-    pub color_texture_id: TextureId,
+    pub color_texture_id: SourceTexture,
     pub color: ColorF,
     pub render_mode: FontRenderMode,
 }
@@ -413,7 +412,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: is_opaque,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::Rectangle,
@@ -432,7 +431,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: false,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::TextRun,
@@ -451,7 +450,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: false,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::Image,
@@ -470,7 +469,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: false,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::Border,
@@ -490,7 +489,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: false,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::Gradient,
@@ -539,7 +538,7 @@ impl PrimitiveStore {
 
                 let metadata = PrimitiveMetadata {
                     is_opaque: false,
-                    mask_texture_id: TextureId::invalid(),
+                    mask_texture_id: SourceTexture::Invalid,
                     clip_index: None,
                     clip_source: clip_source,
                     prim_kind: PrimitiveKind::BoxShadow,
@@ -729,7 +728,7 @@ impl PrimitiveStore {
                 let gpu_data = self.gpu_data32.get_slice_mut(gpu_address, 6);
                 Self::populate_clip_data(gpu_data, data);
                 metadata.clip_index = Some(gpu_address);
-                metadata.mask_texture_id = dummy_mask_cache_item.texture_id;
+                metadata.mask_texture_id = SourceTexture::TextureCache(dummy_mask_cache_item.texture_id);
             }
         }