src/cobalt/renderer/rasterizer/skia/hardware_rasterizer.cc - cobalt - Git at Google

 /*
  * Copyright 2014 Google Inc. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "cobalt/renderer/rasterizer/skia/hardware_rasterizer.h"

 #include <algorithm>

 #include "base/debug/trace_event.h"
 #include "cobalt/renderer/backend/egl/graphics_context.h"
 #include "cobalt/renderer/backend/egl/graphics_system.h"
 #include "cobalt/renderer/frame_rate_throttler.h"
 #include "cobalt/renderer/rasterizer/common/surface_cache.h"
 #include "cobalt/renderer/rasterizer/skia/cobalt_skia_type_conversions.h"
 #include "cobalt/renderer/rasterizer/skia/hardware_resource_provider.h"
 #include "cobalt/renderer/rasterizer/skia/render_tree_node_visitor.h"
 #include "cobalt/renderer/rasterizer/skia/scratch_surface_cache.h"
 #include "cobalt/renderer/rasterizer/skia/surface_cache_delegate.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkSurface.h"
 #include "third_party/skia/include/gpu/GrContext.h"
 #include "third_party/skia/include/gpu/GrTexture.h"
 #include "third_party/skia/include/gpu/SkGrPixelRef.h"
 #include "third_party/skia/src/gpu/SkGpuDevice.h"

 namespace cobalt {
 namespace renderer {
 namespace rasterizer {
 namespace skia {

 class HardwareRasterizer::Impl {
  public:
   Impl(backend::GraphicsContext* graphics_context, int skia_cache_size_in_bytes,
        int scratch_surface_cache_size_in_bytes,
        int surface_cache_size_in_bytes);
   ~Impl();

   void Submit(const scoped_refptr<render_tree::Node>& render_tree,
               const scoped_refptr<backend::RenderTarget>& render_target,
               const Options& options);

   render_tree::ResourceProvider* GetResourceProvider();

  private:
   class CachedScratchSurfaceHolder
       : public RenderTreeNodeVisitor::ScratchSurface {
    public:
     CachedScratchSurfaceHolder(ScratchSurfaceCache* cache,
                                const math::Size& size)
         : cached_scratch_surface_(cache, size) {}
     SkSurface* GetSurface() OVERRIDE {
       return cached_scratch_surface_.GetSurface();
     }

    private:
     CachedScratchSurface cached_scratch_surface_;
   };

   SkSurface* CreateSkSurface(const math::Size& size);
   scoped_ptr<RenderTreeNodeVisitor::ScratchSurface> CreateScratchSurface(
       const math::Size& size);

   void ResetSkiaState();

   base::ThreadChecker thread_checker_;

   backend::GraphicsContextEGL* graphics_context_;
   scoped_ptr<render_tree::ResourceProvider> resource_provider_;

   SkAutoTUnref<GrContext> gr_context_;

   SkAutoTUnref<SkSurface> sk_output_surface_;

   base::optional<ScratchSurfaceCache> scratch_surface_cache_;

   base::optional<SurfaceCacheDelegate> surface_cache_delegate_;
   base::optional<common::SurfaceCache> surface_cache_;

   FrameRateThrottler frame_rate_throttler_;
 };

 namespace {

 SkSurfaceProps GetRenderTargetSurfaceProps() {
   return SkSurfaceProps(SkSurfaceProps::kUseDistanceFieldFonts_Flag,
                         SkSurfaceProps::kLegacyFontHost_InitType);
 }

 SkSurface* CreateSkiaRenderTargetSurface(GrRenderTarget* render_target) {
   SkSurfaceProps surface_props = GetRenderTargetSurfaceProps();
   return SkSurface::NewRenderTargetDirect(render_target, &surface_props);
 }

 // Takes meta-data from a Cobalt RenderTarget object and uses it to fill out
 // a Skia backend render target descriptor.  Additionally, it also references
 // the actual render target object as well so that Skia can then recover
 // the Cobalt render target object.
 GrBackendRenderTargetDesc CobaltRenderTargetToSkiaBackendRenderTargetDesc(
     cobalt::renderer::backend::RenderTarget* cobalt_render_target) {
   const math::Size& size = cobalt_render_target->GetSize();

   GrBackendRenderTargetDesc skia_desc;
   skia_desc.fWidth = size.width();
   skia_desc.fHeight = size.height();
   skia_desc.fConfig = kRGBA_8888_GrPixelConfig;
   skia_desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
   skia_desc.fSampleCnt = 0;
   skia_desc.fStencilBits = 0;
   skia_desc.fRenderTargetHandle =
       static_cast<GrBackendObject>(cobalt_render_target->GetPlatformHandle());

   return skia_desc;
 }

 }  // namespace

 HardwareRasterizer::Impl::Impl(backend::GraphicsContext* graphics_context,
                                int skia_cache_size_in_bytes,
                                int scratch_surface_cache_size_in_bytes,
                                int surface_cache_size_in_bytes)
     : graphics_context_(
           base::polymorphic_downcast<backend::GraphicsContextEGL*>(
               graphics_context)) {
   TRACE_EVENT0("cobalt::renderer", "HardwareRasterizer::Impl::Impl()");

   DLOG(INFO) << "skia_cache_size_in_bytes: " << skia_cache_size_in_bytes;
   DLOG(INFO) << "scratch_surface_cache_size_in_bytes: "
              << scratch_surface_cache_size_in_bytes;
   DLOG(INFO) << "surface_cache_size_in_bytes: " << surface_cache_size_in_bytes;

   graphics_context_->MakeCurrent();
   // Create a GrContext object that wraps the passed in Cobalt GraphicsContext
   // object.
   gr_context_.reset(GrContext::Create(
       kCobalt_GrBackend,
       reinterpret_cast<GrBackendContext>(graphics_context_)));
   DCHECK(gr_context_);
   // The GrContext manages a resource cache internally using GrResourceCache
   // which by default caches 96MB of resources.  This is used for helping with
   // rendering shadow effects, gradient effects, and software rendered paths.
   // As we have our own cache for most resources, set it to a much smaller value
   // so Skia doesn't use too much GPU memory.
   const int kSkiaCacheMaxResources = 128;
   gr_context_->setResourceCacheLimits(kSkiaCacheMaxResources,
                                       skia_cache_size_in_bytes);

   base::Callback<SkSurface*(const math::Size&)> create_sk_surface_function =
       base::Bind(&HardwareRasterizer::Impl::CreateSkSurface,
                  base::Unretained(this));

   scratch_surface_cache_.emplace(create_sk_surface_function,
                                  scratch_surface_cache_size_in_bytes);

   // Setup a resource provider for resources to be used with a hardware
   // accelerated Skia rasterizer.
   resource_provider_.reset(
       new HardwareResourceProvider(graphics_context_, gr_context_));
   graphics_context_->ReleaseCurrentContext();

   int max_surface_size = std::max(gr_context_->getMaxRenderTargetSize(),
                                   gr_context_->getMaxTextureSize());
   DLOG(INFO) << "Max renderer surface size: " << max_surface_size;

   if (surface_cache_size_in_bytes > 0) {
     surface_cache_delegate_.emplace(
         create_sk_surface_function,
         math::Size(max_surface_size, max_surface_size));

     surface_cache_.emplace(&surface_cache_delegate_.value(),
                            surface_cache_size_in_bytes);
   }
 }

 HardwareRasterizer::Impl::~Impl() {
   graphics_context_->MakeCurrent();
   sk_output_surface_.reset(NULL);
   surface_cache_ = base::nullopt;
   surface_cache_delegate_ = base::nullopt;
   scratch_surface_cache_ = base::nullopt;
   gr_context_.reset(NULL);
   graphics_context_->ReleaseCurrentContext();
 }

 void HardwareRasterizer::Impl::Submit(
     const scoped_refptr<render_tree::Node>& render_tree,
     const scoped_refptr<backend::RenderTarget>& render_target,
     const Options& options) {
   DCHECK(thread_checker_.CalledOnValidThread());

   backend::RenderTargetEGL* render_target_egl =
       base::polymorphic_downcast<backend::RenderTargetEGL*>(
           render_target.get());

   backend::GraphicsContextEGL::ScopedMakeCurrent scoped_make_current(
       graphics_context_, render_target_egl);

   // First reset the graphics context state for the pending render tree
   // draw calls, in case we have modified state in between.
   gr_context_->resetContext();

   // Update our surface cache to do per-frame calculations such as deciding
   // which render tree nodes are candidates for caching in this upcoming
   // frame.
   if (surface_cache_) {
     surface_cache_->Frame();
   }

   if (!sk_output_surface_) {
     // Setup a Skia render target that wraps the passed in Cobalt render target.
     SkAutoTUnref<GrRenderTarget> skia_render_target(
         gr_context_->wrapBackendRenderTarget(
             CobaltRenderTargetToSkiaBackendRenderTargetDesc(
                 render_target.get())));

     // Create an SkSurface from the render target so that we can acquire a
     // SkCanvas object from it in Submit().
     sk_output_surface_.reset(CreateSkiaRenderTargetSurface(skia_render_target));
   }

   // Get a SkCanvas that outputs to our hardware render target.
   SkCanvas* canvas = sk_output_surface_->getCanvas();
   canvas->save();

   if (options.flags & Rasterizer::kSubmitFlags_Clear) {
     canvas->clear(SkColorSetARGB(0, 0, 0, 0));
   } else if (options.dirty) {
     // Only a portion of the display is dirty. Reuse the previous frame
     // if possible.
     if (render_target_egl->IsContentPreservedOnSwap() &&
         render_target_egl->swap_count() >= 3) {
       canvas->clipRect(CobaltRectFToSkiaRect(*options.dirty));
     }
   }

   {
     TRACE_EVENT0("cobalt::renderer", "VisitRenderTree");
     // Rasterize the passed in render tree to our hardware render target.
     RenderTreeNodeVisitor::CreateScratchSurfaceFunction
         create_scratch_surface_function =
             base::Bind(&HardwareRasterizer::Impl::CreateScratchSurface,
                        base::Unretained(this));
     RenderTreeNodeVisitor visitor(
         canvas, &create_scratch_surface_function,
         base::Bind(&HardwareRasterizer::Impl::ResetSkiaState,
                    base::Unretained(this)),
         surface_cache_delegate_ ? &surface_cache_delegate_.value() : NULL,
         surface_cache_ ? &surface_cache_.value() : NULL);
     render_tree->Accept(&visitor);
   }

   {
     TRACE_EVENT0("cobalt::renderer", "Skia Flush");
     canvas->flush();
   }

   frame_rate_throttler_.EndInterval();
   graphics_context_->SwapBuffers(render_target_egl);
   frame_rate_throttler_.BeginInterval();
   canvas->restore();
 }

 render_tree::ResourceProvider* HardwareRasterizer::Impl::GetResourceProvider() {
   return resource_provider_.get();
 }

 SkSurface* HardwareRasterizer::Impl::CreateSkSurface(const math::Size& size) {
   TRACE_EVENT2("cobalt::renderer", "HardwareRasterizer::CreateSkSurface()",
                "width", size.width(), "height", size.height());

   // Create a texture of the specified size.  Then convert it to a render
   // target and then convert that to a SkSurface which we return.
   GrTextureDesc target_surface_desc;
   target_surface_desc.fFlags =
       kRenderTarget_GrTextureFlagBit | kNoStencil_GrTextureFlagBit;
   target_surface_desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
   target_surface_desc.fWidth = size.width();
   target_surface_desc.fHeight = size.height();
   target_surface_desc.fConfig = kRGBA_8888_GrPixelConfig;
   target_surface_desc.fSampleCnt = 0;

   SkAutoTUnref<GrTexture> skia_texture(
       gr_context_->createUncachedTexture(target_surface_desc, NULL, 0));
   if (!skia_texture) {
     // If we failed at creating a texture, try again using a different texture
     // format.
     target_surface_desc.fConfig = kBGRA_8888_GrPixelConfig;
     skia_texture.reset(
         gr_context_->createUncachedTexture(target_surface_desc, NULL, 0));
   }
   if (!skia_texture) {
     return NULL;
   }

   GrRenderTarget* skia_render_target = skia_texture->asRenderTarget();
   DCHECK(skia_render_target);

   SkSurfaceProps surface_props = GetRenderTargetSurfaceProps();
   return SkSurface::NewRenderTargetDirect(skia_render_target, &surface_props);
 }

 scoped_ptr<RenderTreeNodeVisitor::ScratchSurface>
 HardwareRasterizer::Impl::CreateScratchSurface(const math::Size& size) {
   TRACE_EVENT2("cobalt::renderer", "HardwareRasterizer::CreateScratchImage()",
                "width", size.width(), "height", size.height());

   scoped_ptr<CachedScratchSurfaceHolder> scratch_surface(
       new CachedScratchSurfaceHolder(&scratch_surface_cache_.value(), size));
   if (scratch_surface->GetSurface()) {
     return scratch_surface.PassAs<RenderTreeNodeVisitor::ScratchSurface>();
   } else {
     return scoped_ptr<RenderTreeNodeVisitor::ScratchSurface>();
   }
 }

 void HardwareRasterizer::Impl::ResetSkiaState() { gr_context_->resetContext(); }

 HardwareRasterizer::HardwareRasterizer(
     backend::GraphicsContext* graphics_context, int skia_cache_size_in_bytes,
     int scratch_surface_cache_size_in_bytes, int surface_cache_size_in_bytes)
     : impl_(new Impl(graphics_context, skia_cache_size_in_bytes,
                      scratch_surface_cache_size_in_bytes,
                      surface_cache_size_in_bytes)) {}

 HardwareRasterizer::~HardwareRasterizer() {}

 void HardwareRasterizer::Submit(
     const scoped_refptr<render_tree::Node>& render_tree,
     const scoped_refptr<backend::RenderTarget>& render_target,
     const Options& options) {
   TRACE_EVENT0("cobalt::renderer", "Rasterizer::Submit()");
   TRACE_EVENT0("cobalt::renderer", "HardwareRasterizer::Submit()");
   impl_->Submit(render_tree, render_target, options);
 }

 render_tree::ResourceProvider* HardwareRasterizer::GetResourceProvider() {
   return impl_->GetResourceProvider();
 }

 }  // namespace skia
 }  // namespace rasterizer
 }  // namespace renderer
 }  // namespace cobalt
	/*
	* Copyright 2014 Google Inc. All Rights Reserved.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "cobalt/renderer/rasterizer/skia/hardware_rasterizer.h"

	#include <algorithm>

	#include "base/debug/trace_event.h"
	#include "cobalt/renderer/backend/egl/graphics_context.h"
	#include "cobalt/renderer/backend/egl/graphics_system.h"
	#include "cobalt/renderer/frame_rate_throttler.h"
	#include "cobalt/renderer/rasterizer/common/surface_cache.h"
	#include "cobalt/renderer/rasterizer/skia/cobalt_skia_type_conversions.h"
	#include "cobalt/renderer/rasterizer/skia/hardware_resource_provider.h"
	#include "cobalt/renderer/rasterizer/skia/render_tree_node_visitor.h"
	#include "cobalt/renderer/rasterizer/skia/scratch_surface_cache.h"
	#include "cobalt/renderer/rasterizer/skia/surface_cache_delegate.h"
	#include "third_party/skia/include/core/SkCanvas.h"
	#include "third_party/skia/include/core/SkSurface.h"
	#include "third_party/skia/include/gpu/GrContext.h"
	#include "third_party/skia/include/gpu/GrTexture.h"
	#include "third_party/skia/include/gpu/SkGrPixelRef.h"
	#include "third_party/skia/src/gpu/SkGpuDevice.h"

	namespace cobalt {
	namespace renderer {
	namespace rasterizer {
	namespace skia {

	class HardwareRasterizer::Impl {
	public:
	Impl(backend::GraphicsContext* graphics_context, int skia_cache_size_in_bytes,
	int scratch_surface_cache_size_in_bytes,
	int surface_cache_size_in_bytes);
	~Impl();

	void Submit(const scoped_refptr<render_tree::Node>& render_tree,
	const scoped_refptr<backend::RenderTarget>& render_target,
	const Options& options);

	render_tree::ResourceProvider* GetResourceProvider();

	private:
	class CachedScratchSurfaceHolder
	: public RenderTreeNodeVisitor::ScratchSurface {
	public:
	CachedScratchSurfaceHolder(ScratchSurfaceCache* cache,
	const math::Size& size)
	: cached_scratch_surface_(cache, size) {}
	SkSurface* GetSurface() OVERRIDE {
	return cached_scratch_surface_.GetSurface();
	}

	private:
	CachedScratchSurface cached_scratch_surface_;
	};

	SkSurface* CreateSkSurface(const math::Size& size);
	scoped_ptr<RenderTreeNodeVisitor::ScratchSurface> CreateScratchSurface(
	const math::Size& size);

	void ResetSkiaState();

	base::ThreadChecker thread_checker_;

	backend::GraphicsContextEGL* graphics_context_;
	scoped_ptr<render_tree::ResourceProvider> resource_provider_;

	SkAutoTUnref<GrContext> gr_context_;

	SkAutoTUnref<SkSurface> sk_output_surface_;

	base::optional<ScratchSurfaceCache> scratch_surface_cache_;

	base::optional<SurfaceCacheDelegate> surface_cache_delegate_;
	base::optional<common::SurfaceCache> surface_cache_;

	FrameRateThrottler frame_rate_throttler_;
	};

	namespace {

	SkSurfaceProps GetRenderTargetSurfaceProps() {
	return SkSurfaceProps(SkSurfaceProps::kUseDistanceFieldFonts_Flag,
	SkSurfaceProps::kLegacyFontHost_InitType);
	}

	SkSurface* CreateSkiaRenderTargetSurface(GrRenderTarget* render_target) {
	SkSurfaceProps surface_props = GetRenderTargetSurfaceProps();
	return SkSurface::NewRenderTargetDirect(render_target, &surface_props);
	}

	// Takes meta-data from a Cobalt RenderTarget object and uses it to fill out
	// a Skia backend render target descriptor. Additionally, it also references
	// the actual render target object as well so that Skia can then recover
	// the Cobalt render target object.
	GrBackendRenderTargetDesc CobaltRenderTargetToSkiaBackendRenderTargetDesc(
	cobalt::renderer::backend::RenderTarget* cobalt_render_target) {
	const math::Size& size = cobalt_render_target->GetSize();

	GrBackendRenderTargetDesc skia_desc;
	skia_desc.fWidth = size.width();
	skia_desc.fHeight = size.height();
	skia_desc.fConfig = kRGBA_8888_GrPixelConfig;
	skia_desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
	skia_desc.fSampleCnt = 0;
	skia_desc.fStencilBits = 0;
	skia_desc.fRenderTargetHandle =
	static_cast<GrBackendObject>(cobalt_render_target->GetPlatformHandle());

	return skia_desc;
	}

	} // namespace

	HardwareRasterizer::Impl::Impl(backend::GraphicsContext* graphics_context,
	int skia_cache_size_in_bytes,
	int scratch_surface_cache_size_in_bytes,
	int surface_cache_size_in_bytes)
	: graphics_context_(
	base::polymorphic_downcast<backend::GraphicsContextEGL*>(
	graphics_context)) {
	TRACE_EVENT0("cobalt::renderer", "HardwareRasterizer::Impl::Impl()");

	DLOG(INFO) << "skia_cache_size_in_bytes: " << skia_cache_size_in_bytes;
	DLOG(INFO) << "scratch_surface_cache_size_in_bytes: "
	<< scratch_surface_cache_size_in_bytes;
	DLOG(INFO) << "surface_cache_size_in_bytes: " << surface_cache_size_in_bytes;

	graphics_context_->MakeCurrent();
	// Create a GrContext object that wraps the passed in Cobalt GraphicsContext
	// object.
	gr_context_.reset(GrContext::Create(
	kCobalt_GrBackend,
	reinterpret_cast<GrBackendContext>(graphics_context_)));
	DCHECK(gr_context_);
	// The GrContext manages a resource cache internally using GrResourceCache
	// which by default caches 96MB of resources. This is used for helping with
	// rendering shadow effects, gradient effects, and software rendered paths.
	// As we have our own cache for most resources, set it to a much smaller value
	// so Skia doesn't use too much GPU memory.
	const int kSkiaCacheMaxResources = 128;
	gr_context_->setResourceCacheLimits(kSkiaCacheMaxResources,
	skia_cache_size_in_bytes);

	base::Callback<SkSurface*(const math::Size&)> create_sk_surface_function =
	base::Bind(&HardwareRasterizer::Impl::CreateSkSurface,
	base::Unretained(this));

	scratch_surface_cache_.emplace(create_sk_surface_function,
	scratch_surface_cache_size_in_bytes);

	// Setup a resource provider for resources to be used with a hardware
	// accelerated Skia rasterizer.
	resource_provider_.reset(
	new HardwareResourceProvider(graphics_context_, gr_context_));
	graphics_context_->ReleaseCurrentContext();

	int max_surface_size = std::max(gr_context_->getMaxRenderTargetSize(),
	gr_context_->getMaxTextureSize());
	DLOG(INFO) << "Max renderer surface size: " << max_surface_size;

	if (surface_cache_size_in_bytes > 0) {
	surface_cache_delegate_.emplace(
	create_sk_surface_function,
	math::Size(max_surface_size, max_surface_size));

	surface_cache_.emplace(&surface_cache_delegate_.value(),
	surface_cache_size_in_bytes);
	}
	}

	HardwareRasterizer::Impl::~Impl() {
	graphics_context_->MakeCurrent();
	sk_output_surface_.reset(NULL);
	surface_cache_ = base::nullopt;
	surface_cache_delegate_ = base::nullopt;
	scratch_surface_cache_ = base::nullopt;
	gr_context_.reset(NULL);
	graphics_context_->ReleaseCurrentContext();
	}

	void HardwareRasterizer::Impl::Submit(
	const scoped_refptr<render_tree::Node>& render_tree,
	const scoped_refptr<backend::RenderTarget>& render_target,
	const Options& options) {
	DCHECK(thread_checker_.CalledOnValidThread());

	backend::RenderTargetEGL* render_target_egl =
	base::polymorphic_downcast<backend::RenderTargetEGL*>(
	render_target.get());

	backend::GraphicsContextEGL::ScopedMakeCurrent scoped_make_current(
	graphics_context_, render_target_egl);

	// First reset the graphics context state for the pending render tree
	// draw calls, in case we have modified state in between.
	gr_context_->resetContext();

	// Update our surface cache to do per-frame calculations such as deciding
	// which render tree nodes are candidates for caching in this upcoming
	// frame.
	if (surface_cache_) {
	surface_cache_->Frame();
	}

	if (!sk_output_surface_) {
	// Setup a Skia render target that wraps the passed in Cobalt render target.
	SkAutoTUnref<GrRenderTarget> skia_render_target(
	gr_context_->wrapBackendRenderTarget(
	CobaltRenderTargetToSkiaBackendRenderTargetDesc(
	render_target.get())));

	// Create an SkSurface from the render target so that we can acquire a
	// SkCanvas object from it in Submit().
	sk_output_surface_.reset(CreateSkiaRenderTargetSurface(skia_render_target));
	}

	// Get a SkCanvas that outputs to our hardware render target.
	SkCanvas* canvas = sk_output_surface_->getCanvas();
	canvas->save();

	if (options.flags & Rasterizer::kSubmitFlags_Clear) {
	canvas->clear(SkColorSetARGB(0, 0, 0, 0));
	} else if (options.dirty) {
	// Only a portion of the display is dirty. Reuse the previous frame
	// if possible.
	if (render_target_egl->IsContentPreservedOnSwap() &&
	render_target_egl->swap_count() >= 3) {
	canvas->clipRect(CobaltRectFToSkiaRect(*options.dirty));
	}
	}

	{
	TRACE_EVENT0("cobalt::renderer", "VisitRenderTree");
	// Rasterize the passed in render tree to our hardware render target.
	RenderTreeNodeVisitor::CreateScratchSurfaceFunction
	create_scratch_surface_function =
	base::Bind(&HardwareRasterizer::Impl::CreateScratchSurface,
	base::Unretained(this));
	RenderTreeNodeVisitor visitor(
	canvas, &create_scratch_surface_function,
	base::Bind(&HardwareRasterizer::Impl::ResetSkiaState,
	base::Unretained(this)),
	surface_cache_delegate_ ? &surface_cache_delegate_.value() : NULL,
	surface_cache_ ? &surface_cache_.value() : NULL);
	render_tree->Accept(&visitor);
	}

	{
	TRACE_EVENT0("cobalt::renderer", "Skia Flush");
	canvas->flush();
	}

	frame_rate_throttler_.EndInterval();
	graphics_context_->SwapBuffers(render_target_egl);
	frame_rate_throttler_.BeginInterval();
	canvas->restore();
	}

	render_tree::ResourceProvider* HardwareRasterizer::Impl::GetResourceProvider() {
	return resource_provider_.get();
	}

	SkSurface* HardwareRasterizer::Impl::CreateSkSurface(const math::Size& size) {
	TRACE_EVENT2("cobalt::renderer", "HardwareRasterizer::CreateSkSurface()",
	"width", size.width(), "height", size.height());

	// Create a texture of the specified size. Then convert it to a render
	// target and then convert that to a SkSurface which we return.
	GrTextureDesc target_surface_desc;
	target_surface_desc.fFlags =
	kRenderTarget_GrTextureFlagBit \| kNoStencil_GrTextureFlagBit;
	target_surface_desc.fOrigin = kBottomLeft_GrSurfaceOrigin;
	target_surface_desc.fWidth = size.width();
	target_surface_desc.fHeight = size.height();
	target_surface_desc.fConfig = kRGBA_8888_GrPixelConfig;
	target_surface_desc.fSampleCnt = 0;

	SkAutoTUnref<GrTexture> skia_texture(
	gr_context_->createUncachedTexture(target_surface_desc, NULL, 0));
	if (!skia_texture) {
	// If we failed at creating a texture, try again using a different texture
	// format.
	target_surface_desc.fConfig = kBGRA_8888_GrPixelConfig;
	skia_texture.reset(
	gr_context_->createUncachedTexture(target_surface_desc, NULL, 0));
	}
	if (!skia_texture) {
	return NULL;
	}

	GrRenderTarget* skia_render_target = skia_texture->asRenderTarget();
	DCHECK(skia_render_target);

	SkSurfaceProps surface_props = GetRenderTargetSurfaceProps();
	return SkSurface::NewRenderTargetDirect(skia_render_target, &surface_props);
	}

	scoped_ptr<RenderTreeNodeVisitor::ScratchSurface>
	HardwareRasterizer::Impl::CreateScratchSurface(const math::Size& size) {
	TRACE_EVENT2("cobalt::renderer", "HardwareRasterizer::CreateScratchImage()",
	"width", size.width(), "height", size.height());

	scoped_ptr<CachedScratchSurfaceHolder> scratch_surface(
	new CachedScratchSurfaceHolder(&scratch_surface_cache_.value(), size));
	if (scratch_surface->GetSurface()) {
	return scratch_surface.PassAs<RenderTreeNodeVisitor::ScratchSurface>();
	} else {
	return scoped_ptr<RenderTreeNodeVisitor::ScratchSurface>();
	}
	}

	void HardwareRasterizer::Impl::ResetSkiaState() { gr_context_->resetContext(); }

	HardwareRasterizer::HardwareRasterizer(
	backend::GraphicsContext* graphics_context, int skia_cache_size_in_bytes,
	int scratch_surface_cache_size_in_bytes, int surface_cache_size_in_bytes)
	: impl_(new Impl(graphics_context, skia_cache_size_in_bytes,
	scratch_surface_cache_size_in_bytes,
	surface_cache_size_in_bytes)) {}

	HardwareRasterizer::~HardwareRasterizer() {}

	void HardwareRasterizer::Submit(
	const scoped_refptr<render_tree::Node>& render_tree,
	const scoped_refptr<backend::RenderTarget>& render_target,
	const Options& options) {
	TRACE_EVENT0("cobalt::renderer", "Rasterizer::Submit()");
	TRACE_EVENT0("cobalt::renderer", "HardwareRasterizer::Submit()");
	impl_->Submit(render_tree, render_target, options);
	}

	render_tree::ResourceProvider* HardwareRasterizer::GetResourceProvider() {
	return impl_->GetResourceProvider();
	}

	} // namespace skia
	} // namespace rasterizer
	} // namespace renderer
	} // namespace cobalt