android: Use UIResource for overscroll glow

content/browser/android/overscroll_glow.cc

Index: content/browser/android/overscroll_glow.cc
diff --git a/content/browser/android/overscroll_glow.cc b/content/browser/android/overscroll_glow.cc
index fb491f3ebaacfbd5b4364601e56e10de80b23dbb..49a053f65443fdad8226cbf40eb7ea46738ff4b7 100644
--- a/content/browser/android/overscroll_glow.cc
+++ b/content/browser/android/overscroll_glow.cc
@@ -6,10 +6,8 @@
 
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
-#include "base/threading/worker_pool.h"
-#include "cc/layers/image_layer.h"
+#include "cc/layers/ui_resource_layer.h"
 #include "content/browser/android/edge_effect.h"
-#include "skia/ext/image_operations.h"
 #include "ui/gfx/android/java_bitmap.h"
 
 using std::max;
@@ -20,57 +18,9 @@ namespace content {
 namespace {
 
 const float kEpsilon = 1e-3f;
-const int kScaledEdgeHeight = 12;
-const int kScaledGlowHeight = 64;
 const float kEdgeHeightAtMdpi = 12.f;
 const float kGlowHeightAtMdpi = 128.f;
 
-SkBitmap CreateSkBitmapFromAndroidResource(const char* name, gfx::Size size) {
-  base::android::ScopedJavaLocalRef<jobject> jobj =
-      gfx::CreateJavaBitmapFromAndroidResource(name, size);
-  if (jobj.is_null())
-    return SkBitmap();
-
-  SkBitmap bitmap = CreateSkBitmapFromJavaBitmap(gfx::JavaBitmap(jobj.obj()));
-  if (bitmap.isNull())
-    return bitmap;
-
-  return skia::ImageOperations::Resize(

[powei, 2014/07/08 19:12:43]

I didn't move this over.  I thought BitmapHelper.decodeDrawableResource already
took care of the size?

[jdduke (slow), 2014/07/08 20:10:11]

Unfortunately no, if you look at the comments, decodeDrawableResource will
downsample to the smallest size still *larger* than the provide dimensions that
preserves the aspect ratio (a very cheap operation).  This last resize is to
reduce it further to the exact desired dimensions (slightly more expensive but
still desirable).  I originally had this resize code in the java_bitmap.cc
source as part of CreateJavaBitmapFromAndroidResource, we could move it back
there if this is the only consumer.

[powei, 2014/07/09 20:41:03]

This is the only consumer.  I can move it to java_bitmap.cc

-      bitmap, skia::ImageOperations::RESIZE_BOX, size.width(), size.height());
-}
-
-class OverscrollResources {
- public:
-  OverscrollResources() {
-    TRACE_EVENT0("browser", "OverscrollResources::Create");
-    edge_bitmap_ =
-        CreateSkBitmapFromAndroidResource("android:drawable/overscroll_edge",
-                                          gfx::Size(128, kScaledEdgeHeight));
-    glow_bitmap_ =
-        CreateSkBitmapFromAndroidResource("android:drawable/overscroll_glow",
-                                          gfx::Size(128, kScaledGlowHeight));
-  }
-
-  const SkBitmap& edge_bitmap() const { return edge_bitmap_; }
-  const SkBitmap& glow_bitmap() const { return glow_bitmap_; }
-
- private:
-  SkBitmap edge_bitmap_;
-  SkBitmap glow_bitmap_;
-
-  DISALLOW_COPY_AND_ASSIGN(OverscrollResources);
-};
-
-// Leaky to allow access from a worker thread.
-base::LazyInstance<OverscrollResources>::Leaky g_overscroll_resources =
-    LAZY_INSTANCE_INITIALIZER;
-
-scoped_refptr<cc::Layer> CreateImageLayer(const SkBitmap& bitmap) {
-  scoped_refptr<cc::ImageLayer> layer = cc::ImageLayer::Create();
-  layer->SetBitmap(bitmap);
-  return layer;
-}
-
 bool IsApproxZero(float value) {
   return std::abs(value) < kEpsilon;
 }
@@ -83,20 +33,9 @@ gfx::Vector2dF ZeroSmallComponents(gfx::Vector2dF vector) {
   return vector;
 }
 
-// Force loading of any necessary resources.  This function is thread-safe.
-void EnsureResources() {
-  g_overscroll_resources.Get();
-}
-
 } // namespace
 
 scoped_ptr<OverscrollGlow> OverscrollGlow::Create(bool enabled) {
-  // Don't block the main thread with effect resource loading during creation.
-  // Effect instantiation is deferred until the effect overscrolls, in which
-  // case the main thread may block until the resource has loaded.
-  if (enabled && g_overscroll_resources == NULL)
-    base::WorkerPool::PostTask(FROM_HERE, base::Bind(EnsureResources), true);
-
   return make_scoped_ptr(new OverscrollGlow(enabled));
 }
 
@@ -124,6 +63,8 @@ void OverscrollGlow::Disable() {
 
 bool OverscrollGlow::OnOverscrolled(cc::Layer* overscrolling_layer,
                                     base::TimeTicks current_time,
+                                    cc::UIResourceId edge_ui_resource,
+                                    cc::UIResourceId glow_ui_resource,
                                     gfx::Vector2dF accumulated_overscroll,
                                     gfx::Vector2dF overscroll_delta,
                                     gfx::Vector2dF velocity) {
@@ -142,7 +83,8 @@ bool OverscrollGlow::OnOverscrolled(cc::Layer* overscrolling_layer,
   if (overscroll_delta.IsZero()) {
     if (initialized_) {
       Release(current_time);
-      UpdateLayerAttachment(overscrolling_layer);
+      UpdateLayerAttachment(
+          overscrolling_layer, edge_ui_resource, glow_ui_resource);
     }
     return NeedsAnimate();
   }
@@ -167,7 +109,9 @@ bool OverscrollGlow::OnOverscrolled(cc::Layer* overscrolling_layer,
   else
     Pull(current_time, overscroll_delta);
 
-  UpdateLayerAttachment(overscrolling_layer);
+  UpdateLayerAttachment(
+      overscrolling_layer, edge_ui_resource, glow_ui_resource);
+
   return NeedsAnimate();
 }
 
@@ -210,7 +154,9 @@ bool OverscrollGlow::NeedsAnimate() const {
   return false;
 }
 
-void OverscrollGlow::UpdateLayerAttachment(cc::Layer* parent) {
+void OverscrollGlow::UpdateLayerAttachment(cc::Layer* parent,
+                                           cc::UIResourceId edge_ui_resource,
+                                           cc::UIResourceId glow_ui_resource) {
   DCHECK(parent);
   if (!root_layer_)
     return;
@@ -222,6 +168,12 @@ void OverscrollGlow::UpdateLayerAttachment(cc::Layer* parent) {
 
   if (root_layer_->parent() != parent)
     parent->AddChild(root_layer_);
+
+  // UIResources addition needs to take place after layer attachment.
+  for (size_t i = 0; i < EdgeEffect::EDGE_COUNT; ++i) {
+    if (edge_effects_[i])
+      edge_effects_[i]->SetUIResources(edge_ui_resource, glow_ui_resource);
+  }
 }
 
 void OverscrollGlow::Detach() {
@@ -234,18 +186,13 @@ bool OverscrollGlow::InitializeIfNecessary() {
   if (initialized_)
     return true;
 
-  const SkBitmap& edge = g_overscroll_resources.Get().edge_bitmap();
-  const SkBitmap& glow = g_overscroll_resources.Get().glow_bitmap();
-  if (edge.isNull() || glow.isNull()) {
-    Disable();
-    return false;
-  }
-
   DCHECK(!root_layer_);
   root_layer_ = cc::Layer::Create();
   for (size_t i = 0; i < EdgeEffect::EDGE_COUNT; ++i) {
-    scoped_refptr<cc::Layer> edge_layer = CreateImageLayer(edge);
-    scoped_refptr<cc::Layer> glow_layer = CreateImageLayer(glow);
+    scoped_refptr<cc::UIResourceLayer> edge_layer =
+        cc::UIResourceLayer::Create();
+    scoped_refptr<cc::UIResourceLayer> glow_layer =
+        cc::UIResourceLayer::Create();
     root_layer_->AddChild(edge_layer);
     root_layer_->AddChild(glow_layer);
     edge_effects_[i] = make_scoped_ptr(new EdgeEffect(edge_layer, glow_layer));