Bug 1330945 - Part1. Apply opacity to webrender stacking context as an opacity filter. r=jrmuizel

gfx/layers/ipc/WebRenderMessages.ipdlh

@@ -29,6 +29,7 @@ struct OpDPPushStackingContext {
   WrRect bounds;
   WrRect overflow;
   MaybeImageMask mask;
+  float opacity;
   Animation[] animations;
   Matrix4x4 matrix;
   WrMixBlendMode mixBlendMode;

gfx/layers/wr/WebRenderBorderLayer.cpp

@@ -47,6 +47,7 @@ WebRenderBorderLayer::RenderLayer()
       OpDPPushStackingContext(wr::ToWrRect(relBounds),
                               wr::ToWrRect(overflow),
                               Nothing(),
+                              1.0f,
                               GetAnimations(),
                               transform,
                               WrMixBlendMode::Normal,

gfx/layers/wr/WebRenderBridgeParent.cpp

@@ -311,7 +311,7 @@ WebRenderBridgeParent::ProcessWebrenderCommands(InfallibleTArray<WebRenderComman
     switch (cmd.type()) {
       case WebRenderCommand::TOpDPPushStackingContext: {
         const OpDPPushStackingContext& op = cmd.get_OpDPPushStackingContext();
-        builder.PushStackingContext(op.bounds(), op.overflow(), op.mask().ptrOr(nullptr), op.matrix(), op.mixBlendMode());
+        builder.PushStackingContext(op.bounds(), op.overflow(), op.mask().ptrOr(nullptr), op.opacity(), op.matrix(), op.mixBlendMode());
         break;
       }
       case WebRenderCommand::TOpDPPopStackingContext: {

gfx/layers/wr/WebRenderCanvasLayer.cpp

@@ -92,6 +92,7 @@ WebRenderCanvasLayer::RenderLayer()
       OpDPPushStackingContext(wr::ToWrRect(relBounds),
                               wr::ToWrRect(overflow),
                               mask,
+                              1.0f,
                               GetAnimations(),
                               transform,
                               mixBlendMode,

gfx/layers/wr/WebRenderColorLayer.cpp

@@ -50,6 +50,7 @@ WebRenderColorLayer::RenderLayer()
       OpDPPushStackingContext(wr::ToWrRect(relBounds),
                               wr::ToWrRect(overflow),
                               mask,
+                              1.0f,
                               GetAnimations(),
                               transform,
                               mixBlendMode,

gfx/layers/wr/WebRenderContainerLayer.cpp

@@ -39,6 +39,7 @@ WebRenderContainerLayer::RenderLayer()
     OpDPPushStackingContext(wr::ToWrRect(relBounds),
                             wr::ToWrRect(overflow),
                             mask,
+                            GetLocalOpacity(),
                             GetLayer()->GetAnimations(),
                             transform,
                             mixBlendMode,

gfx/layers/wr/WebRenderImageLayer.cpp

@@ -160,6 +160,7 @@ WebRenderImageLayer::RenderLayer()
     OpDPPushStackingContext(wr::ToWrRect(relBounds),
                             wr::ToWrRect(overflow),
                             mask,
+                            1.0f,
                             GetAnimations(),
                             transform,
                             mixBlendMode,

gfx/layers/wr/WebRenderLayerManager.cpp

@@ -161,6 +161,7 @@ WrScrollFrameStackingContextGenerator::WrScrollFrameStackingContextGenerator(
       OpDPPushStackingContext(wr::ToWrRect(bounds),
                               wr::ToWrRect(overflow),
                               Nothing(),
+                              1.0f,
                               layer->GetAnimations(),
                               identity,
                               WrMixBlendMode::Normal,

gfx/layers/wr/WebRenderPaintedLayer.cpp

@@ -162,6 +162,7 @@ WebRenderPaintedLayer::RenderLayer()
       OpDPPushStackingContext(wr::ToWrRect(relBounds),
                               wr::ToWrRect(overflow),
                               mask,
+                              1.0f,
                               GetAnimations(),
                               transform,
                               mixBlendMode,

gfx/webrender_bindings/WebRenderAPI.cpp

@@ -342,10 +342,11 @@ void
 DisplayListBuilder::PushStackingContext(const WrRect& aBounds,
                                         const WrRect& aOverflow,
                                         const WrImageMask* aMask,
+                                        const float aOpacity,
                                         const gfx::Matrix4x4& aTransform,
                                         const WrMixBlendMode& aMixBlendMode)
 {
-  wr_dp_push_stacking_context(mWrState, aBounds, aOverflow, aMask,
+  wr_dp_push_stacking_context(mWrState, aBounds, aOverflow, aMask, aOpacity,
                               &aTransform.components[0], aMixBlendMode);
 }
 

gfx/webrender_bindings/WebRenderAPI.h

@@ -108,6 +108,7 @@ public:
   void PushStackingContext(const WrRect& aBounds, // TODO: We should work with strongly typed rects
                            const WrRect& aOverflow,
                            const WrImageMask* aMask, // TODO: needs a wrapper.
+                           const float aOpacity,
                            const gfx::Matrix4x4& aTransform,
                            const WrMixBlendMode& aMixBlendMode);
 

gfx/webrender_bindings/src/bindings.rs

@@ -8,7 +8,7 @@ use gleam::gl;
 use webrender_traits::{BorderSide, BorderStyle, BorderRadius};
 use webrender_traits::{PipelineId, ClipRegion};
 use webrender_traits::{Epoch, ColorF, GlyphInstance, ImageDescriptor};
-use webrender_traits::{ImageData, ImageFormat, ImageKey, ImageMask, ImageRendering, RendererKind, MixBlendMode};
+use webrender_traits::{FilterOp, ImageData, ImageFormat, ImageKey, ImageMask, ImageRendering, RendererKind, MixBlendMode};
 use webrender_traits::{ExternalImageId, RenderApi, FontKey};
 use webrender_traits::{DeviceUintSize, ExternalEvent};
 use webrender_traits::{LayoutPoint, LayoutRect, LayoutSize, LayoutTransform};
@@ -561,7 +561,7 @@ pub extern fn wr_window_dp_begin(window: &mut WrWindowState, state: &mut WrState
 }
 
 #[no_mangle]
-pub extern fn wr_dp_push_stacking_context(state:&mut WrState, bounds: WrRect, overflow: WrRect, mask: *const WrImageMask, transform: &LayoutTransform, mix_blend_mode: WrMixBlendMode)
+pub extern fn wr_dp_push_stacking_context(state:&mut WrState, bounds: WrRect, overflow: WrRect, mask: *const WrImageMask, opacity: f32, transform: &LayoutTransform, mix_blend_mode: WrMixBlendMode)
 {
     assert!( unsafe { is_in_compositor_thread() });
     state.z_index += 1;
@@ -574,6 +574,11 @@ pub extern fn wr_dp_push_stacking_context(state:&mut WrState, bounds: WrRect, ov
 
     let clip_region = state.frame_builder.dl_builder.new_clip_region(&overflow, vec![], mask);
 
+    let mut filters: Vec<FilterOp> = Vec::new();
+    if opacity < 1.0 {
+        filters.push(FilterOp::Opacity(opacity));
+    }
+
     state.frame_builder.dl_builder.push_stacking_context(webrender_traits::ScrollPolicy::Scrollable,
                                   bounds,
                                   clip_region,
@@ -581,7 +586,7 @@ pub extern fn wr_dp_push_stacking_context(state:&mut WrState, bounds: WrRect, ov
                                   transform,
                                   &LayoutTransform::identity(),
                                   mix_blend_mode,
-                                  Vec::new());
+                                  filters);
 
 }
 

gfx/webrender_bindings/webrender_ffi.h

@@ -431,7 +431,8 @@ WR_FUNC;
 WR_INLINE void
 wr_dp_push_stacking_context(WrState *wrState, WrRect bounds,
                             WrRect overflow, const WrImageMask *mask,
-                            const float* matrix, WrMixBlendMode mixBlendMode)
+                            float opacity, const float* matrix,
+                            WrMixBlendMode mixBlendMode)
 WR_FUNC;
 
 //XXX: matrix should use a proper type