[Android WebView] Implement Ubercomp for Render Thread support

android_webview/browser/hardware_renderer.cc

 // Copyright 2014 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 "android_webview/browser/hardware_renderer.h"
 
 #include "android_webview/browser/aw_gl_surface.h"
-#include "android_webview/browser/browser_view_renderer_client.h"
+#include "android_webview/browser/deferred_gpu_command_service.h"
+#include "android_webview/browser/parent_output_surface.h"
+#include "android_webview/browser/shared_renderer_state.h"
 #include "android_webview/public/browser/draw_gl.h"
+#include "base/auto_reset.h"
 #include "base/debug/trace_event.h"
 #include "base/strings/string_number_conversions.h"
-#include "content/public/browser/android/synchronous_compositor.h"
-#include "content/public/browser/browser_thread.h"
-#include "gpu/command_buffer/service/shader_translator_cache.h"
+#include "cc/layers/delegated_frame_provider.h"
+#include "cc/layers/delegated_renderer_layer.h"
+#include "cc/layers/layer.h"
+#include "cc/output/compositor_frame.h"
+#include "cc/output/output_surface.h"
+#include "cc/trees/layer_tree_host.h"
+#include "cc/trees/layer_tree_settings.h"
+#include "gpu/command_buffer/client/gl_in_process_context.h"
+#include "ui/gfx/frame_time.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/transform.h"
 #include "ui/gl/gl_bindings.h"
+#include "webkit/common/gpu/context_provider_in_process.h"
+#include "webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.h"
 
 namespace android_webview {
 
+namespace {
+
+using webkit::gpu::WebGraphicsContext3DInProcessCommandBufferImpl;
+
+scoped_refptr<cc::ContextProvider> CreateContext(
+    scoped_refptr<gfx::GLSurface> surface,
+    scoped_refptr<gpu::InProcessCommandBuffer::Service> service,
+    gpu::GLInProcessContext* share_context) {
+  const gfx::GpuPreference gpu_preference = gfx::PreferDiscreteGpu;
+
+  blink::WebGraphicsContext3D::Attributes attributes;
+  attributes.antialias = false;
+  attributes.depth = false;
+  attributes.stencil = false;
+  attributes.shareResources = true;
+  attributes.noAutomaticFlushes = true;
+  gpu::GLInProcessContextAttribs in_process_attribs;
+  WebGraphicsContext3DInProcessCommandBufferImpl::ConvertAttributes(
+      attributes, &in_process_attribs);
+  in_process_attribs.lose_context_when_out_of_memory = 1;
+
+  scoped_ptr<gpu::GLInProcessContext> context(
+      gpu::GLInProcessContext::Create(service,
+                                      surface,
+                                      surface->IsOffscreen(),
+                                      gfx::kNullAcceleratedWidget,
+                                      surface->GetSize(),
+                                      share_context,
+                                      false /* share_resources */,
+                                      in_process_attribs,
+                                      gpu_preference));
+  DCHECK(context.get());
+
+  return webkit::gpu::ContextProviderInProcess::Create(
+      WebGraphicsContext3DInProcessCommandBufferImpl::WrapContext(
+          context.Pass(), attributes),
+      "Parent-Compositor");
+}
+
+}  // namespace
+
 HardwareRenderer::HardwareRenderer(SharedRendererState* state)
     : shared_renderer_state_(state),
-      last_egl_context_(eglGetCurrentContext()) {
+      last_egl_context_(eglGetCurrentContext()),
+      view_width_(-1),
+      view_height_(-1),
+      viewport_clip_valid_for_dcheck_(false),
+      root_layer_(cc::Layer::Create()),
+      output_surface_(NULL) {
   DCHECK(last_egl_context_);
 
   gl_surface_ = new AwGLSurface;
-  bool success =
-      shared_renderer_state_->GetCompositor()->
-          InitializeHwDraw(gl_surface_);
-  DCHECK(success);
+
+  cc::LayerTreeSettings settings;
+
+  // Should be kept in sync with compositor_impl_android.cc.
+  settings.allow_antialiasing = false;
+  settings.highp_threshold_min = 2048;
+
+  // Webview does not own the surface so should not clear it.
+  settings.should_clear_root_render_pass = false;
+
+  layer_tree_host_ =
+      cc::LayerTreeHost::CreateSingleThreaded(this, this, NULL, settings);
+  layer_tree_host_->SetRootLayer(root_layer_);
+  layer_tree_host_->SetLayerTreeHostClientReady();
 }
 
 HardwareRenderer::~HardwareRenderer() {
-  shared_renderer_state_->GetCompositor()->ReleaseHwDraw();
-  gl_surface_ = NULL;
+  // Must reset everything before |resource_collection_| to ensure all
+  // resources are returned before resetting |resource_collection_| client.
+  layer_tree_host_.reset();
+  root_layer_ = NULL;
+  delegated_layer_ = NULL;
+  frame_provider_ = NULL;
+  if (resource_collection_.get()) {
+#if DCHECK_IS_ON
+    // Check collection is empty.
+    cc::ReturnedResourceArray returned_resources;
+    resource_collection_->TakeUnusedResourcesForChildCompositor(
+        &returned_resources);
+    DCHECK_EQ(0u, returned_resources.size());
+#endif  // DCHECK_IS_ON
+
+    resource_collection_->SetClient(NULL);
+  }
+}
+
+void HardwareRenderer::DidBeginMainFrame() {
+  // This is called after OutputSurface is created, but before the impl frame
+  // starts. We set the draw constraints here.
+  DCHECK(output_surface_);
+  DCHECK(viewport_clip_valid_for_dcheck_);
+  output_surface_->SetDrawConstraints(viewport_, clip_);
 }
 
 bool HardwareRenderer::DrawGL(bool stencil_enabled,
                               int framebuffer_binding_ext,
                               AwDrawGLInfo* draw_info,
                               DrawGLResult* result) {
   TRACE_EVENT0("android_webview", "HardwareRenderer::DrawGL");
 
   // We need to watch if the current Android context has changed and enforce
   // a clean-up in the compositor.
   EGLContext current_context = eglGetCurrentContext();
   if (!current_context) {
     DLOG(ERROR) << "DrawGL called without EGLContext";
     return false;
   }
 
   // TODO(boliu): Handle context loss.
   if (last_egl_context_ != current_context)
     DLOG(WARNING) << "EGLContextChanged";
 
-  if (draw_info->mode != AwDrawGLInfo::kModeDraw)
-    return false;
+  scoped_ptr<DrawGLInput> input = shared_renderer_state_->PassDrawGLInput();
+  if (!resource_collection_.get()) {
+    resource_collection_ = new cc::DelegatedFrameResourceCollection;
+    resource_collection_->SetClient(this);
+  }
 
-  // Should only need to access SharedRendererState in kModeDraw and kModeSync.
-  const DrawGLInput input = shared_renderer_state_->GetDrawGLInput();
-  SetCompositorMemoryPolicy();
+  if (input.get()) {
+    DCHECK(!input->frame.gl_frame_data);
+    DCHECK(!input->frame.software_frame_data);
+
+    bool size_changed =
+        input->width != view_width_ || input->height != view_height_;
+    view_width_ = input->width;
+    view_height_ = input->height;
+    scroll_offset_ = input->scroll_offset;
+
+    if (!frame_provider_ || size_changed) {
+      if (delegated_layer_) {
+        delegated_layer_->RemoveFromParent();
+      }
+
+      frame_provider_ = new cc::DelegatedFrameProvider(
+          resource_collection_.get(), input->frame.delegated_frame_data.Pass());
+
+      delegated_layer_ = cc::DelegatedRendererLayer::Create(frame_provider_);
+      delegated_layer_->SetBounds(gfx::Size(view_width_, view_height_));
+      delegated_layer_->SetIsDrawable(true);
+      delegated_layer_->SetAnchorPoint(gfx::PointF(0.f, 0.f));
+
+      root_layer_->AddChild(delegated_layer_);
+    } else {
+      frame_provider_->SetFrameData(input->frame.delegated_frame_data.Pass());
+    }
+  }
+
+  viewport_.SetSize(draw_info->width, draw_info->height);
+  layer_tree_host_->SetViewportSize(viewport_);
+  clip_.SetRect(draw_info->clip_left,
+                draw_info->clip_top,
+                draw_info->clip_right - draw_info->clip_left,
+                draw_info->clip_bottom - draw_info->clip_top);
+
+  gfx::Transform transform(gfx::Transform::kSkipInitialization);
+  transform.matrix().setColMajorf(draw_info->transform);
+  transform.Translate(scroll_offset_.x(), scroll_offset_.y());
+  delegated_layer_->SetTransform(transform);
 
   gl_surface_->SetBackingFrameBufferObject(framebuffer_binding_ext);
-
-  gfx::Transform transform;
-  transform.matrix().setColMajorf(draw_info->transform);
-  transform.Translate(input.scroll_offset.x(), input.scroll_offset.y());
-  gfx::Rect clip_rect(draw_info->clip_left,
-                      draw_info->clip_top,
-                      draw_info->clip_right - draw_info->clip_left,
-                      draw_info->clip_bottom - draw_info->clip_top);
-
-  gfx::Rect viewport(draw_info->width, draw_info->height);
-  if (!draw_info->is_layer) {
-    gfx::RectF view_rect(input.width, input.height);
-    transform.TransformRect(&view_rect);
-    viewport.Intersect(gfx::ToEnclosingRect(view_rect));
+  {
+    base::AutoReset<bool> frame_resetter(&viewport_clip_valid_for_dcheck_,
+                                         true);
+    layer_tree_host_->SetNeedsRedrawRect(clip_);
+    layer_tree_host_->Composite(gfx::FrameTime::Now());
   }
-
-  bool did_draw = shared_renderer_state_->GetCompositor()->DemandDrawHw(
-      gfx::Size(draw_info->width, draw_info->height),
-      transform,
-      viewport,
-      clip_rect,
-      stencil_enabled);
   gl_surface_->ResetBackingFrameBufferObject();
 
-  if (did_draw) {
-    result->frame_id = input.frame_id;
-    result->clip_contains_visible_rect =
-        clip_rect.Contains(input.global_visible_rect);
-  }
-  return did_draw;
+  return true;
 }
 
-void HardwareRenderer::SetCompositorMemoryPolicy() {
-  if (shared_renderer_state_->IsMemoryPolicyDirty()) {
-    content::SynchronousCompositorMemoryPolicy policy =
-        shared_renderer_state_->GetMemoryPolicy();
-    // Memory policy is set by BrowserViewRenderer on UI thread.
-    shared_renderer_state_->GetCompositor()->SetMemoryPolicy(policy);
-    shared_renderer_state_->SetMemoryPolicyDirty(false);
-  }
+scoped_ptr<cc::OutputSurface> HardwareRenderer::CreateOutputSurface(
+    bool fallback) {
+  // Android webview does not support losing output surface.
+  DCHECK(!fallback);
+  scoped_refptr<cc::ContextProvider> context_provider =
+      CreateContext(gl_surface_,
+                    DeferredGpuCommandService::GetInstance(),
+                    shared_renderer_state_->GetSharedContext());
+  scoped_ptr<ParentOutputSurface> output_surface_holder(
+      new ParentOutputSurface(context_provider));
+  output_surface_ = output_surface_holder.get();
+  return output_surface_holder.PassAs<cc::OutputSurface>();
+}
+
+void HardwareRenderer::UnusedResourcesAreAvailable() {
+  cc::ReturnedResourceArray returned_resources;
+  resource_collection_->TakeUnusedResourcesForChildCompositor(
+      &returned_resources);
+  shared_renderer_state_->InsertReturnedResources(returned_resources);
 }
 
 }  // namespace android_webview