Bug 950312 - Part 2: Add Effect for BlendModes. r=nical

gfx/layers/CompositorTypes.h

@@ -140,6 +140,7 @@ MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(DiagnosticFlags)
  */
 MOZ_BEGIN_ENUM_CLASS(EffectTypes, uint8_t)
   MASK,
+  BLEND_MODE,
   MAX_SECONDARY, // sentinel for the count of secondary effect types
   RGB,
   YCBCR,

gfx/layers/Effects.cpp

@@ -54,3 +54,10 @@ EffectSolidColor::PrintInfo(nsACString& aTo, const char* aPrefix)
   aTo += nsPrintfCString("EffectSolidColor (0x%p) [color=%x]", this, mColor.ToABGR());
 }
 
+void
+EffectBlendMode::PrintInfo(nsACString& aTo, const char* aPrefix)
+{
+  aTo += aPrefix;
+  aTo += nsPrintfCString("EffectBlendMode (0x%p) [blendmode=%i]", this, (int)mBlendMode);
+}
+

gfx/layers/Effects.h

@@ -96,6 +96,19 @@ struct EffectMask : public Effect
   gfx::Matrix4x4 mMaskTransform;
 };
 
+struct EffectBlendMode : public Effect
+{
+  EffectBlendMode(gfx::CompositionOp aBlendMode)
+    : Effect(EffectTypes::BLEND_MODE)
+    , mBlendMode(aBlendMode)
+  { }
+
+  virtual const char* Name() { return "EffectBlendMode"; }
+  virtual void PrintInfo(nsACString& aTo, const char* aPrefix);
+
+  gfx::CompositionOp mBlendMode;
+};
+
 // Render to a render target rather than the screen.
 struct EffectRenderTarget : public TexturedEffect
 {

gfx/layers/composite/CanvasLayerComposite.cpp

@@ -99,6 +99,7 @@ CanvasLayerComposite::RenderLayer(const nsIntRect& aClipRect)
 #endif
 
   EffectChain effectChain(this);
+  AddBlendModeEffect(effectChain);
 
   LayerManagerComposite::AutoAddMaskEffect autoMaskEffect(mMaskLayer, effectChain);
   gfx::Rect clipRect(aClipRect.x, aClipRect.y, aClipRect.width, aClipRect.height);

gfx/layers/composite/ColorLayerComposite.cpp

@@ -41,6 +41,8 @@ ColorLayerComposite::RenderLayer(const nsIntRect& aClipRect)
 
   float opacity = GetEffectiveOpacity();
 
+  AddBlendModeEffect(effects);
+
   const gfx::Matrix4x4& transform = GetEffectiveTransform();
   mCompositor->DrawQuad(rect, clipRect, effects, opacity, transform);
   mCompositor->DrawDiagnostics(DiagnosticFlags::COLOR,

gfx/layers/composite/ContainerLayerComposite.cpp

@@ -400,6 +400,7 @@ ContainerRender(ContainerT* aContainer,
                                                             effectChain,
                                                             !aContainer->GetTransform().CanDraw2D());
 
+    aContainer->AddBlendModeEffect(effectChain);
     effectChain.mPrimaryEffect = new EffectRenderTarget(surface);
 
     gfx::Rect rect(visibleRect.x, visibleRect.y, visibleRect.width, visibleRect.height);

gfx/layers/composite/ImageLayerComposite.cpp

@@ -100,6 +100,7 @@ ImageLayerComposite::RenderLayer(const nsIntRect& aClipRect)
 
   EffectChain effectChain(this);
   LayerManagerComposite::AutoAddMaskEffect autoMaskEffect(mMaskLayer, effectChain);
+  AddBlendModeEffect(effectChain);
 
   gfx::Rect clipRect(aClipRect.x, aClipRect.y, aClipRect.width, aClipRect.height);
   mImageHost->SetCompositor(mCompositor);

gfx/layers/composite/LayerManagerComposite.cpp

@@ -914,6 +914,18 @@ LayerComposite::Destroy()
   }
 }
 
+void
+LayerComposite::AddBlendModeEffect(EffectChain& aEffectChain)
+{
+  gfx::CompositionOp blendMode = GetLayer()->GetEffectiveMixBlendMode();
+  if (blendMode == gfx::CompositionOp::OP_OVER) {
+    return;
+  }
+
+  aEffectChain.mSecondaryEffects[EffectTypes::BLEND_MODE] = new EffectBlendMode(blendMode);
+  return;
+}
+
 bool
 LayerManagerComposite::CanUseCanvasLayerForSize(const IntSize &aSize)
 {

gfx/layers/composite/LayerManagerComposite.h

@@ -338,6 +338,8 @@ public:
 
   virtual void DestroyFrontBuffer() { }
 
+  void AddBlendModeEffect(EffectChain& aEffectChain);
+
   /**
    * The following methods are
    *

gfx/layers/composite/ThebesLayerComposite.cpp

@@ -130,6 +130,7 @@ ThebesLayerComposite::RenderLayer(const nsIntRect& aClipRect)
 
   EffectChain effectChain(this);
   LayerManagerComposite::AutoAddMaskEffect autoMaskEffect(mMaskLayer, effectChain);
+  AddBlendModeEffect(effectChain);
 
   nsIntRegion visibleRegion = GetEffectiveVisibleRegion();