Very basic Android browser-side compositing support.

content/browser/renderer_host/compositor_impl_android.cc

+// Copyright (c) 2012 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/renderer_host/compositor_impl_android.h"
+
+#include "base/bind.h"
+#include "base/logging.h"
+#include "content/browser/android/graphics_context.h"
+#include "content/browser/gpu/browser_gpu_channel_host_factory.h"
+#include "content/common/gpu/client/gpu_channel_host.h"
+#include "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
+#include "content/common/gpu/gpu_process_launch_causes.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebCompositor.h"
+
+namespace content {
+
+// static
+Compositor* Compositor::Create() {
+  return new CompositorImpl();
+}
+
+CompositorImpl::CompositorImpl()
+    : root_layer_(WebKit::WebLayer::create()) {
+}
+
+CompositorImpl::~CompositorImpl() {
+}
+
+void CompositorImpl::OnSurfaceUpdated(
+    const SurfacePresentedCallback& callback) {
+  host_.composite();
+  uint32 sync_point = context_->InsertSyncPoint();
+  callback.Run(sync_point);
+}
+
+void CompositorImpl::SetRootLayer(WebKit::WebLayer* root_layer) {
+  root_layer_->removeAllChildren();
+  root_layer_->addChild(root_layer);
+}
+
+void CompositorImpl::SetWindowSurface(ANativeWindow* window) {
+  if (window) {
+    context_.reset(GraphicsContext::CreateForUI(window));
+    WebKit::WebCompositor::initialize(NULL);

[klobag.chromium, 2012/08/28 00:12:07]

If SurfaceView is shown and hidden and shown again, SetWindowSurface will be
called with ANativeWindow, NULL, ANativeWindow, will this initialization do
twice? Will it have any side effect?

[no sievers, 2012/08/29 02:30:50]

Done. Added a static Compositor::Initialize() function to be called by the app.

+    WebKit::WebLayerTreeView::Settings settings;
+    settings.refreshRate = 60.0;
+    host_.initialize(this, *root_layer_, settings);
+    host_.setVisible(true);
+    host_.setSurfaceReady();
+  } else {
+    context_.reset(NULL);

[klobag.chromium, 2012/08/28 00:12:07]

Should you reset size_ as you use it to compare in SetWindowBounds?

[no sievers, 2012/08/29 02:30:50]

Done.

+  }
+}
+
+void CompositorImpl::SetWindowBounds(const gfx::Size& size) {
+  if (size_ == size)
+    return;
+
+  size_ = size;
+  host_.setViewportSize(size);
+  root_layer_->setBounds(size);
+}
+
+void CompositorImpl::updateAnimations(double frameBeginTime) {
+}
+
+void CompositorImpl::layout() {
+}
+
+void CompositorImpl::applyScrollAndScale(const WebKit::WebSize& scrollDelta,
+                                     float scaleFactor) {
+}
+
+WebKit::WebGraphicsContext3D* CompositorImpl::createContext3D() {
+  WebKit::WebGraphicsContext3D::Attributes attrs;

[klobag.chromium, 2012/08/28 00:12:07]

Should you check context_ for null first as it may be reset?

[no sievers, 2012/08/29 02:30:50]

Done.

+  attrs.shareResources = true;
+  GpuChannelHostFactory* factory = BrowserGpuChannelHostFactory::instance();
+  GURL url("chrome://gpu/Compositor::createContext3D");
+  base::WeakPtr<WebGraphicsContext3DSwapBuffersClient> swap_client;
+  scoped_ptr<WebGraphicsContext3DCommandBufferImpl> context(
+      new WebGraphicsContext3DCommandBufferImpl(
+          context_->GetSurfaceID(),
+          url,
+          factory,
+          swap_client));
+  if (!context->Initialize(
+      attrs,
+      false,
+      CAUSE_FOR_GPU_LAUNCH_WEBGRAPHICSCONTEXT3DCOMMANDBUFFERIMPL_INITIALIZE)) {
+    return NULL;
+  }
+
+  return context.release();
+}
+
+void CompositorImpl::didRebindGraphicsContext(bool success) {
+}
+
+void CompositorImpl::didCommit() {
+}
+
+void CompositorImpl::didCommitAndDrawFrame() {
+}
+
+void CompositorImpl::didCompleteSwapBuffers() {
+}
+
+void CompositorImpl::scheduleComposite() {
+}
+
+} // namespace content