Bug 1234485 - Part 10. Paint mask onto mask layer when possible. r=mattwoodrow,mstange

MozReview-Commit-ID: GEMprzpfYw3

--HG--
extra : rebase_source : aa72a7b84ed21fae5638b5a83b2e739716537864
extra : intermediate-source : 6b90195d53da590b153c0ee7317767ae15ef6b16
extra : source : fcd9d758f37adb4d28f2fd72b458f1576e5cd2f8

layout/base/FrameLayerBuilder.cpp

@@ -3940,6 +3940,23 @@ ContainerState::SetupMaskLayerForCSSMask(Layer* aLayer,
     return;
   }
 
+  RefPtr<gfxContext> maskCtx = gfxContext::CreateOrNull(dt);
+  gfxPoint offset = nsLayoutUtils::PointToGfxPoint(bounds.TopLeft(), A2D);
+  maskCtx->SetMatrix(gfxMatrix::Translation(-offset));
+
+  if (!aMaskItem->PaintMask(mBuilder, maskCtx)) {
+    // Mostly because of mask resource is not ready.
+    return;
+  }
+
+  // Setup mask layer offset.
+  Matrix4x4 matrix;
+  matrix.PreTranslate(offset.x, offset.y, 0);
+  matrix.PreTranslate(mParameters.mOffset.x, mParameters.mOffset.y, 0);
+  matrix.PreScale(mParameters.mXScale, mParameters.mYScale, 1.0);
+
+  maskLayer->SetBaseTransform(matrix);
+
   RefPtr<ImageContainer> imgContainer =
     imageData.CreateImageAndImageContainer();
   if (!imgContainer) {
@@ -4354,6 +4371,9 @@ ContainerState::ProcessDisplayItems(nsDisplayList* aList)
             SetupMaskLayer(ownLayer, layerClip);
           }
         }
+      } else if (item->GetType() == nsDisplayItem::TYPE_MASK) {
+        nsDisplayMask* maskItem = static_cast<nsDisplayMask*>(item);
+        SetupMaskLayerForCSSMask(ownLayer, maskItem);
       }
 
       ContainerLayer* oldContainer = ownLayer->GetParent();

layout/base/nsDisplayList.cpp

@@ -7052,6 +7052,25 @@ nsDisplayMask::BuildLayer(nsDisplayListBuilder* aBuilder,
   return container.forget();
 }
 
+bool
+nsDisplayMask::PaintMask(nsDisplayListBuilder* aBuilder,
+                         gfxContext* aMaskContext)
+{
+  MOZ_ASSERT(aMaskContext->GetDrawTarget()->GetFormat() == SurfaceFormat::A8);
+
+  nsRect borderArea = nsRect(ToReferenceFrame(), mFrame->GetSize());
+  nsSVGIntegrationUtils::PaintFramesParams params(*aMaskContext,
+                                                  mFrame,  mVisibleRect,
+                                                  borderArea, aBuilder,
+                                                  nullptr,
+                                                  mHandleOpacity);
+  ComputeMaskGeometry(params);
+  image::DrawResult result = nsSVGIntegrationUtils::PaintMask(params);
+
+  nsDisplayMaskGeometry::UpdateDrawResult(this, result);
+  return (result == image::DrawResult::SUCCESS) ? true : false;
+}
+
 LayerState
 nsDisplayMask::GetLayerState(nsDisplayListBuilder* aBuilder,
                              LayerManager* aManager,
@@ -7141,6 +7160,8 @@ nsDisplayMask::PaintAsLayer(nsDisplayListBuilder* aBuilder,
                             nsRenderingContext* aCtx,
                             LayerManager* aManager)
 {
+  MOZ_ASSERT(!ShouldPaintOnMaskLayer(aManager));
+
   nsRect borderArea = nsRect(ToReferenceFrame(), mFrame->GetSize());
   nsSVGIntegrationUtils::PaintFramesParams params(*aCtx->ThebesContext(),
                                                   mFrame,  mVisibleRect,

layout/base/nsDisplayList.h

@@ -3878,6 +3878,9 @@ protected:
  */
 class nsDisplayMask : public nsDisplaySVGEffects {
 public:
+  typedef mozilla::layers::ImageLayer ImageLayer;
+  typedef class mozilla::gfx::DrawTarget DrawTarget;
+
   nsDisplayMask(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
                 nsDisplayList* aList, bool aHandleOpacity,
                 const DisplayItemScrollClip* aScrollClip);
@@ -3913,6 +3916,11 @@ public:
                     nsRenderingContext* aCtx,
                     LayerManager* aManager);
 
+  /*
+   * Paint mask onto aMaskContext in mFrame's coordinate space.
+   */
+  bool PaintMask(nsDisplayListBuilder* aBuilder, gfxContext* aMaskContext);
+
   const nsTArray<nsRect>& GetDestRects()
   {
     return mDestRects;