From 795df1327bc714102d31bc179e66e3f24e3b6674 Mon Sep 17 00:00:00 2001
From: Adam Barth <abarth@chromium.org>
Date: Wed, 26 Aug 2015 09:26:51 -0700
Subject: [PATCH] Plumb physical size along with SkPicture

Previously we were using the cull rect of the SkPicture to size the GPU buffer,
but Skia is too smart and shrinkwraps the cull rect, which meant we weren't
sizing the GPU buffer to the right size.

Fixes #814
---
 sky/shell/gpu/rasterizer.cc | 14 +-------------
 sky/shell/gpu/rasterizer.h  |  2 +-
 sky/shell/gpu_delegate.h    |  3 ++-
 sky/shell/ui/animator.cc    |  3 ++-
 sky/shell/ui/engine.h       |  1 +
 5 files changed, 7 insertions(+), 16 deletions(-)

diff --git a/sky/shell/gpu/rasterizer.cc b/sky/shell/gpu/rasterizer.cc
index dc4530c8a0f..d2e930d6f17 100644
--- a/sky/shell/gpu/rasterizer.cc
+++ b/sky/shell/gpu/rasterizer.cc
@@ -17,14 +17,6 @@
 
 namespace sky {
 namespace shell {
-namespace {
-
-gfx::Size GetSize(SkPicture* picture) {
-  const SkRect& rect = picture->cullRect();
-  return gfx::Size(rect.width(), rect.height());
-}
-
-}  // namespace
 
 Rasterizer::Rasterizer()
     : share_group_(new gfx::GLShareGroup()), weak_factory_(this) {
@@ -43,16 +35,12 @@ void Rasterizer::OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget) {
   CHECK(surface_) << "GLSurface required.";
 }
 
-void Rasterizer::Draw(PassRefPtr<SkPicture> picture) {
+void Rasterizer::Draw(PassRefPtr<SkPicture> picture, gfx::Size size) {
   TRACE_EVENT0("sky", "Rasterizer::Draw");
 
   if (!surface_)
     return;
 
-  gfx::Size size = GetSize(picture.get());
-  if (size.IsEmpty())
-    return;
-
   if (surface_->GetSize() != size)
     surface_->Resize(size);
 
diff --git a/sky/shell/gpu/rasterizer.h b/sky/shell/gpu/rasterizer.h
index 09d5a755cba..ff8b687ac2a 100644
--- a/sky/shell/gpu/rasterizer.h
+++ b/sky/shell/gpu/rasterizer.h
@@ -34,7 +34,7 @@ class Rasterizer : public GPUDelegate {
 
   void OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget) override;
   void OnOutputSurfaceDestroyed() override;
-  void Draw(PassRefPtr<SkPicture> picture) override;
+  void Draw(PassRefPtr<SkPicture> picture, gfx::Size size) override;
 
  private:
   void EnsureGLContext();
diff --git a/sky/shell/gpu_delegate.h b/sky/shell/gpu_delegate.h
index cebc6eb2071..43cca28cffa 100644
--- a/sky/shell/gpu_delegate.h
+++ b/sky/shell/gpu_delegate.h
@@ -6,6 +6,7 @@
 #define SKY_SHELL_GPU_DELEGATE_H_
 
 #include "sky/engine/wtf/PassRefPtr.h"
+#include "ui/gfx/geometry/size.h"
 #include "ui/gfx/native_widget_types.h"
 
 class SkPicture;
@@ -17,7 +18,7 @@ class GPUDelegate {
  public:
   virtual void OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget) = 0;
   virtual void OnOutputSurfaceDestroyed() = 0;
-  virtual void Draw(PassRefPtr<SkPicture> picture) = 0;
+  virtual void Draw(PassRefPtr<SkPicture> picture, gfx::Size size) = 0;
 
  protected:
   virtual ~GPUDelegate();
diff --git a/sky/shell/ui/animator.cc b/sky/shell/ui/animator.cc
index 521bef8df21..1fc37546fcb 100644
--- a/sky/shell/ui/animator.cc
+++ b/sky/shell/ui/animator.cc
@@ -76,7 +76,8 @@ void Animator::BeginFrame(int64_t time_stamp) {
 
   config_.gpu_task_runner->PostTaskAndReply(
       FROM_HERE,
-      base::Bind(&GPUDelegate::Draw, config_.gpu_delegate, picture),
+      base::Bind(&GPUDelegate::Draw, config_.gpu_delegate, picture,
+                 engine_->physical_size()),
       base::Bind(&Animator::OnFrameComplete, weak_factory_.GetWeakPtr()));
 }
 
diff --git a/sky/shell/ui/engine.h b/sky/shell/ui/engine.h
index bbb0248bddf..105b2b14ba1 100644
--- a/sky/shell/ui/engine.h
+++ b/sky/shell/ui/engine.h
@@ -56,6 +56,7 @@ class Engine : public UIDelegate,
 
   void BeginFrame(base::TimeTicks frame_time);
   PassRefPtr<SkPicture> Paint();
+  const gfx::Size& physical_size() { return physical_size_; }
 
   void StartDartTracing();
   void StopDartTracing(mojo::ScopedDataPipeProducerHandle producer);