Add FBO support in Android WebView

content/browser/android/in_process/synchronous_compositor_output_surface.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/android/in_process/synchronous_compositor_output_surface.h"
 
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "cc/output/begin_frame_args.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/context_provider.h"
 #include "cc/output/managed_memory_policy.h"
 #include "cc/output/output_surface_client.h"
 #include "cc/output/software_output_device.h"
 #include "content/browser/android/in_process/synchronous_compositor_impl.h"
 #include "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
 #include "content/public/browser/browser_thread.h"
+#include "gpu/command_buffer/client/gl_in_process_context.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkDevice.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/transform.h"
 #include "ui/gl/gl_context.h"
 #include "webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.h"
 
-using webkit::gpu::WebGraphicsContext3DInProcessCommandBufferImpl;
 
 namespace content {
 
 namespace {
 
-// TODO(boliu): RenderThreadImpl should create in process contexts as well.
-scoped_ptr<WebKit::WebGraphicsContext3D> CreateWebGraphicsContext3D() {
+scoped_ptr<WebKit::WebGraphicsContext3D> CreateWebGraphicsContext3D(
+    scoped_refptr<gfx::GLSurface> surface) {
+  using webkit::gpu::WebGraphicsContext3DInProcessCommandBufferImpl;
+  if (!gfx::GLSurface::InitializeOneOff())
+    scoped_ptr<WebKit::WebGraphicsContext3D>();
+
+  // TODO(boliu): Much of this code is copied or adapted from
+  // WebGraphicsContext3DInProcessCommandBufferImpl. Refactor and reduce
+  // code duplication.
+  const bool offscreen = false;
+  const gfx::Size size(1, 1);
+  const char* allowed_extensions = "*";
+  const gfx::GpuPreference gpu_preference = gfx::PreferDiscreteGpu;
+
   WebKit::WebGraphicsContext3D::Attributes attributes;
   attributes.antialias = false;
   attributes.shareResources = true;
   attributes.noAutomaticFlushes = true;
+  const int alpha_size = attributes.alpha ? 8 : 0;
+  const int depth_size = attributes.depth ? 24 : 0;
+  const int stencil_size = attributes.stencil ? 8 : 0;
+  const int samples = attributes.antialias ? 4 : 0;
+  const int sample_buffers = attributes.antialias ? 1 : 0;
+  const int32 attribs[] = {
+    gpu::GLInProcessContext::ALPHA_SIZE, alpha_size,
+    gpu::GLInProcessContext::DEPTH_SIZE, depth_size,
+    gpu::GLInProcessContext::STENCIL_SIZE, stencil_size,
+    gpu::GLInProcessContext::SAMPLES, samples,
+    gpu::GLInProcessContext::SAMPLE_BUFFERS, sample_buffers,
+    gpu::GLInProcessContext::NONE,
+  };
+
+  scoped_ptr<gpu::GLInProcessContext> context(
+      gpu::GLInProcessContext::CreateWithSurface(surface,
+                                                 offscreen,
+                                                 size,
+                                                 attributes.shareResources,
+                                                 allowed_extensions,
+                                                 attribs,
+                                                 gpu_preference));
+
+  if (!context.get())
+    scoped_ptr<WebKit::WebGraphicsContext3D>();
 
   return scoped_ptr<WebKit::WebGraphicsContext3D>(
-      WebGraphicsContext3DInProcessCommandBufferImpl
-          ::CreateViewContext(attributes, NULL));
+      WebGraphicsContext3DInProcessCommandBufferImpl::WrapContext(
+          context.Pass(), attributes));
 }
 
 void DidActivatePendingTree(int routing_id) {
   SynchronousCompositorOutputSurfaceDelegate* delegate =
       SynchronousCompositorImpl::FromRoutingID(routing_id);
   if (delegate)
     delegate->DidActivatePendingTree();
 }
 
 } // namespace
@@ skipping 121 matching lines @@
   // origin of the clip rect, but CC's draw origin starts at the clip.
   transform->matrix().postTranslate(-clip.x(), -clip.y(), 0);
 }
 } // namespace
 
 bool SynchronousCompositorOutputSurface::InitializeHwDraw(
     scoped_refptr<cc::ContextProvider> offscreen_context) {
   DCHECK(CalledOnValidThread());
   DCHECK(HasClient());
   DCHECK(!context3d_);
+  DCHECK(!surface_);
 
-  return InitializeAndSetContext3D(CreateWebGraphicsContext3D().Pass(),
-                                   offscreen_context);
+  surface_ = new gfx::GLSurfaceStub;
+  bool success = InitializeAndSetContext3D(
+      CreateWebGraphicsContext3D(surface_).Pass(), offscreen_context);
+  if (!success)
+    surface_ = NULL;
+
+  return success;
 }
 
 void SynchronousCompositorOutputSurface::ReleaseHwDraw() {
+  DCHECK(surface_);
   cc::OutputSurface::ReleaseGL();
+  surface_ = NULL;
 }
 
 bool SynchronousCompositorOutputSurface::DemandDrawHw(
     gfx::Size surface_size,
     const gfx::Transform& transform,
     gfx::Rect clip,
     bool stencil_enabled) {
   DCHECK(CalledOnValidThread());
   DCHECK(HasClient());
   DCHECK(context3d());
+  DCHECK(surface_);
+
+  surface_->SaveCurrentFBO();
 
   gfx::Transform adjusted_transform = transform;
   AdjustTransformForClip(&adjusted_transform, clip);
   surface_size_ = surface_size;
   SetExternalDrawConstraints(adjusted_transform, clip);
   SetExternalStencilTest(stencil_enabled);
   InvokeComposite(clip.size());
 
-  // TODO(boliu): Check if context is lost here.
-
   return did_swap_buffer_;
 }
 
 bool SynchronousCompositorOutputSurface::DemandDrawSw(SkCanvas* canvas) {
   DCHECK(CalledOnValidThread());
   DCHECK(canvas);
   DCHECK(!current_sw_canvas_);
   base::AutoReset<SkCanvas*> canvas_resetter(&current_sw_canvas_, canvas);
 
   SkIRect canvas_clip;
@@ skipping 38 matching lines @@
 bool SynchronousCompositorOutputSurface::CalledOnValidThread() const {
   return BrowserThread::CurrentlyOn(BrowserThread::UI);
 }
 
 SynchronousCompositorOutputSurfaceDelegate*
 SynchronousCompositorOutputSurface::GetDelegate() {
   return SynchronousCompositorImpl::FromRoutingID(routing_id_);
 }
 
 }  // namespace content