cc: Adding support for RGBA_4444 tile textures

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 3d6607c18fa19c8573752f1b58f0317c3884ce01..eb30d4e6eea652f06fd04469f168ae5cacc1f205 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -662,8 +662,8 @@ scoped_ptr<ScopedResource> GLRenderer::DrawBackgroundFilters(
   scoped_ptr<ScopedResource> device_background_texture =
       ScopedResource::create(resource_provider_);
   if (!device_background_texture->Allocate(window_rect.size(),
-                                           GL_RGB,
-                                           ResourceProvider::TextureUsageAny)) {
+                                           ResourceProvider::TextureUsageAny,
+                                           RGBA_8888)) {
     return scoped_ptr<ScopedResource>();
   } else {
     ResourceProvider::ScopedWriteLockGL lock(resource_provider_,
@@ -688,8 +688,8 @@ scoped_ptr<ScopedResource> GLRenderer::DrawBackgroundFilters(
   scoped_ptr<ScopedResource> background_texture =
       ScopedResource::create(resource_provider_);
   if (!background_texture->Allocate(quad->rect.size(),
-                                    GL_RGBA,
-                                    ResourceProvider::TextureUsageFramebuffer))
+                                    ResourceProvider::TextureUsageFramebuffer,
+                                    RGBA_8888))
     return scoped_ptr<ScopedResource>();
 
   const RenderPass* target_render_pass = frame->current_render_pass;
@@ -1711,10 +1711,10 @@ void GLRenderer::DrawPictureQuad(const DrawingFrame* frame,
 
     on_demand_tile_raster_resource_id_ = resource_provider_->CreateGLTexture(
         quad->texture_size,
-        GL_RGBA,
         GL_TEXTURE_POOL_UNMANAGED_CHROMIUM,
         GL_CLAMP_TO_EDGE,
-        ResourceProvider::TextureUsageAny);
+        ResourceProvider::TextureUsageAny,
+        settings_->use_rgba_4444_textures ? RGBA_4444 : RGBA_8888);

[reveman, 2013/09/14 00:58:39]

I think this should be using resource_provider->best_tile_texture_format()
instead?

[kaanb, 2013/09/16 07:22:25]

Yes, since previously GL_RGBA was hardcoded, raster-on-demand pixel tests were
expecting the output in GL_RGBA format. When I changed this to use
best_tile_texture_format() those tests started failing since
best_tile_texture_format() was BGRA, so I added a field to LayerTreeSettings to
enforce using RGBA textures to fix the tests.

   }
 
   SkBitmapDevice device(on_demand_tile_raster_bitmap_);
@@ -1723,9 +1723,20 @@ void GLRenderer::DrawPictureQuad(const DrawingFrame* frame,
   quad->picture_pile->RasterToBitmap(&canvas, quad->content_rect,
                                      quad->contents_scale, NULL);
 
+  const uint8_t* bitmap_pixels = NULL;
+  if (settings_->use_rgba_4444_textures) {

[reveman, 2013/09/14 00:58:39]

I think this code should be similar to PBRWP code and not use
use_rgba_4444_textures directly. You might want to move the helper function you
added to PBRWP to resource_format.h.

[kaanb, 2013/09/16 07:22:25]

Done.

+    on_demand_tile_raster_bitmap_.copyTo(
+        &on_demand_tile_raster_bitmap_4444_, SkBitmap::kARGB_4444_Config);
+    bitmap_pixels = reinterpret_cast<uint8_t*>(
+        on_demand_tile_raster_bitmap_4444_.getPixels());

[reveman, 2013/09/14 00:58:39]

does caching on_demand_tile_raster_bitmap_4444_ really make a difference? I'd
prefer if this was just a temporary variable like in the case of PBRWP for now.

[kaanb, 2013/09/16 07:22:25]

Done.

+  } else {
+    bitmap_pixels = reinterpret_cast<uint8_t*>(
+        on_demand_tile_raster_bitmap_.getPixels());
+  }
+
   resource_provider_->SetPixels(
       on_demand_tile_raster_resource_id_,
-      reinterpret_cast<uint8_t*>(on_demand_tile_raster_bitmap_.getPixels()),
+      bitmap_pixels,
       gfx::Rect(quad->texture_size),
       gfx::Rect(quad->texture_size),
       gfx::Vector2d());
@@ -2214,7 +2225,7 @@ void GLRenderer::GetFramebufferPixelsAsync(
         GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));
     GLC(context_, context_->texParameteri(
         GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE));
-    GetFramebufferTexture(texture_id, GL_RGBA, window_rect);
+    GetFramebufferTexture(texture_id, RGBA_8888, window_rect);
 
     gpu::Mailbox mailbox;
     unsigned sync_point = 0;
@@ -2306,7 +2317,7 @@ void GLRenderer::DoGetFramebufferPixels(
     // Copy the contents of the current (IOSurface-backed) framebuffer into a
     // temporary texture.
     GetFramebufferTexture(temporary_texture,
-                          GL_RGBA,
+                          RGBA_8888,
                           gfx::Rect(current_surface_size_));
     temporary_fbo = context_->createFramebuffer();
     // Attach this texture to an FBO, and perform the readback from that FBO.
@@ -2456,9 +2467,8 @@ void GLRenderer::PassOnSkBitmap(
     request->SendBitmapResult(bitmap.Pass());
 }
 
-void GLRenderer::GetFramebufferTexture(unsigned texture_id,
-                                       unsigned texture_format,
-                                       gfx::Rect window_rect) {
+void GLRenderer::GetFramebufferTexture(
+    unsigned texture_id, ResourceFormat texture_format, gfx::Rect window_rect) {
   DCHECK(texture_id);
   DCHECK_GE(window_rect.x(), 0);
   DCHECK_GE(window_rect.y(), 0);
@@ -2467,14 +2477,15 @@ void GLRenderer::GetFramebufferTexture(unsigned texture_id,
 
   GLC(context_, context_->bindTexture(GL_TEXTURE_2D, texture_id));
   GLC(context_,
-      context_->copyTexImage2D(GL_TEXTURE_2D,
-                               0,
-                               texture_format,
-                               window_rect.x(),
-                               window_rect.y(),
-                               window_rect.width(),
-                               window_rect.height(),
-                               0));
+      context_->copyTexImage2D(
+          GL_TEXTURE_2D,
+          0,
+          ResourceProvider::GetGLDataFormat(texture_format),
+          window_rect.x(),
+          window_rect.y(),
+          window_rect.width(),
+          window_rect.height(),
+          0));
   GLC(context_, context_->bindTexture(GL_TEXTURE_2D, 0));
 }