Add FBO support in Android WebView

content/browser/android/in_process/synchronous_compositor_output_surface.cc

Index: content/browser/android/in_process/synchronous_compositor_output_surface.cc
diff --git a/content/browser/android/in_process/synchronous_compositor_output_surface.cc b/content/browser/android/in_process/synchronous_compositor_output_surface.cc
index fafd06fda22c7268b4f5d38024cee0196389259e..71afad6a6ffd572b671a6c5f05966bb59e9d741c 100644
--- a/content/browser/android/in_process/synchronous_compositor_output_surface.cc
+++ b/content/browser/android/in_process/synchronous_compositor_output_surface.cc
@@ -15,6 +15,7 @@
 #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"
@@ -23,22 +24,55 @@
 #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>();
+
+  bool offscreen = false;
+  gfx::Size size(1, 1);

[joth, 2013/08/04 00:45:16]

const all these?

comment where the values came from? (esp 1x1 is ok because.....)

[boliu, 2013/08/05 16:58:24]

Actually I'm not sure. I'm inclined to say it's not used, but the value is
passed into decoder and saved in the context state...added comment that this is
copied code though

+  const char* allowed_extensions = "*";
+  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,
+  };

[joth, 2013/08/04 00:45:16]

this chunk smells like is was c&p from somewhere. if so comment where. 

+
+  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));

[joth, 2013/08/04 00:45:16]

nit: tend to line these up like line 62-68

[boliu, 2013/08/05 16:58:24]

It doesn't fit on 80 characters. Also this is not against the style guide (since
it was formatted with clang-format) since all arguments fit on a signal line. No
change made.

 }
 
 void DidActivatePendingTree(int routing_id) {
@@ -180,13 +214,17 @@ bool SynchronousCompositorOutputSurface::InitializeHwDraw(
   DCHECK(CalledOnValidThread());
   DCHECK(HasClient());
   DCHECK(!context3d_);
+  DCHECK(!surface_);
 
-  return InitializeAndSetContext3D(CreateWebGraphicsContext3D().Pass(),
+  surface_ = new gfx::GLSurfaceStub;
+  return InitializeAndSetContext3D(CreateWebGraphicsContext3D(surface_).Pass(),
                                    offscreen_context);
 }
 
 void SynchronousCompositorOutputSurface::ReleaseHwDraw() {
+  DCHECK(surface_);
   cc::OutputSurface::ReleaseGL();
+  surface_ = NULL;
 }
 
 bool SynchronousCompositorOutputSurface::DemandDrawHw(
@@ -197,6 +235,9 @@ bool SynchronousCompositorOutputSurface::DemandDrawHw(
   DCHECK(CalledOnValidThread());
   DCHECK(HasClient());
   DCHECK(context3d());
+  DCHECK(surface_);
+
+  surface_->UpdateFBO();
 
   gfx::Transform adjusted_transform = transform;
   AdjustTransformForClip(&adjusted_transform, clip);