aw: Fallback delegated composite

android_webview/browser/browser_view_renderer.cc

Index: android_webview/browser/browser_view_renderer.cc
diff --git a/android_webview/browser/browser_view_renderer.cc b/android_webview/browser/browser_view_renderer.cc
index a79f97d89301400d9a0a6f46f342cb06f4b8d157..5ebcd230c6a18e16658f400341d6e9ce2b2afac2 100644
--- a/android_webview/browser/browser_view_renderer.cc
+++ b/android_webview/browser/browser_view_renderer.cc
@@ -13,7 +13,6 @@
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
-#include "cc/output/compositor_frame.h"

[hush (inactive), 2014/10/15 18:17:30]

why is this removed? we still use cc::compositorFrame right?

[boliu, 2014/10/15 19:37:51]

Added back.

 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
@@ -226,10 +225,6 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
     return false;
 
   ReturnResourceFromParent();
-  SynchronousCompositorMemoryPolicy new_policy = CalculateDesiredMemoryPolicy();
-  RequestMemoryPolicy(new_policy);
-  compositor_->SetMemoryPolicy(memory_policy_);
-
   if (shared_renderer_state_->HasCompositorFrame()) {
     TRACE_EVENT_INSTANT0("android_webview",
                          "EarlyOut_PreviousFrameUnconsumed",
@@ -238,6 +233,19 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
     return client_->RequestDrawGL(java_canvas, false);
   }
 
+  scoped_ptr<cc::CompositorFrame> frame = CompositeHw();
+  if (!frame.get())
+    return false;
+
+  shared_renderer_state_->SetCompositorFrame(frame.Pass(), false);
+  return client_->RequestDrawGL(java_canvas, false);
+}
+
+scoped_ptr<cc::CompositorFrame> BrowserViewRenderer::CompositeHw() {
+  SynchronousCompositorMemoryPolicy new_policy = CalculateDesiredMemoryPolicy();
+  RequestMemoryPolicy(new_policy);
+  compositor_->SetMemoryPolicy(memory_policy_);
+
   parent_draw_constraints_ = shared_renderer_state_->ParentDrawConstraints();
   gfx::Size surface_size(width_, height_);
   gfx::Rect viewport(surface_size);
@@ -262,13 +270,12 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
                                 viewport_rect_for_tile_priority,
                                 transform_for_tile_priority);
   if (!frame.get())
-    return false;
+    return frame.Pass();
 
   GlobalTileManager::GetInstance()->DidUse(tile_manager_key_);
 
-  shared_renderer_state_->SetCompositorFrame(frame.Pass());
   DidComposite();
-  return client_->RequestDrawGL(java_canvas, false);
+  return frame.Pass();
 }
 
 void BrowserViewRenderer::UpdateParentDrawConstraints() {
@@ -710,7 +717,16 @@ void BrowserViewRenderer::FallbackTickFired() {
   DCHECK(block_invalidates_);
   fallback_tick_pending_ = false;
   if (compositor_needs_continuous_invalidate_ && compositor_) {
-    ForceFakeCompositeSW();
+    if (hardware_enabled_) {
+      ReturnResourceFromParent();
+      ReturnUnusedResource(shared_renderer_state_->PassCompositorFrame());

[hush (inactive), 2014/10/15 18:17:30]

there is also a frame in HardwareRenderer.commited_frame_ that could contain
some resources. I think you need to return unused resources too, if you are not
going to SetFrameData twice in HardwareRenderer::DrawGL

[boliu, 2014/10/15 19:37:51]

I am calling SetFrameData twice in HWR::DrawGL :)

+      scoped_ptr<cc::CompositorFrame> frame = CompositeHw();
+      if (frame.get()) {
+        shared_renderer_state_->SetCompositorFrame(frame.Pass(), true);
+      }
+    } else {
+      ForceFakeCompositeSW();
+    }
   } else {
     // Pretend we just composited to unblock further invalidates.
     DidComposite();