Commit 239a5280 authored by Alexis Beingessner's avatar Alexis Beingessner
Browse files

Bug 1435094 - wire up GlyphRasterSpace to nsDisplayTransform. r=kats,mstange 

When a transform thinks it's animated we should abandon screen rasterization
and instead favour local rasterization. This produces a more visually
pleasant rendering, as pixel-snapping "wobbles" the text between
frames.

The float scale of GlyphRasterSpace::Local is currently unused, but this
PR tries its best to set it to a reasonable value, based on discussion
with glennw about the intended semantics. We agreed it should specify
the scale *relative* to the parent stacking context, which means it's
just whatever scaling the stacking context's transform applies. It's
possible we'll need to clamp this value or make it properly 2-dimensional
later on.

Some book-keeping is added to StackingContextHelper to ensure that
GlyphRasterSpace::Screen is never requested by a descendent
of a stacking context using GlyphRasterSpace::Local.

nsDisplayMask is changed to use a StackingContextHelper to ensure
rasterSpace is properly propagated.

In addition, this is the first commit making use of cbindgen's new support
for bridging Rust enums natively into C++! This bumps our minimum cbindgen
to 6.0.0 (just released).

MozReview-Commit-ID: 9AlsB6nUheB

--HG--
extra : rebase_source : 247e5b197e998682cb4bb74f6f9319a9a4dd3264
parent 6dd00bfc

gfx/layers/wr/AsyncImagePipelineManager.cpp

+3 −1
Original line number Diff line number Diff line
@@ -327,7 +327,9 @@ AsyncImagePipelineManager::ApplyAsyncImages() 
                                nullptr,

                                pipeline->mMixBlendMode,

                                nsTArray<wr::WrFilterOp>(),

                                true);

                                true,

                                // This is fine to do unconditionally because we only push images here.

                                wr::GlyphRasterSpace::Screen());



    LayoutDeviceRect rect(0, 0, pipeline->mCurrentTexture->GetSize().width, pipeline->mCurrentTexture->GetSize().height);

    if (pipeline->mScaleToSize.isSome()) {

gfx/layers/wr/StackingContextHelper.cpp

+12 −3
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ StackingContextHelper::StackingContextHelper() 
  , mScale(1.0f, 1.0f)

  , mAffectsClipPositioning(false)

  , mIsPreserve3D(false)

  , mRasterizeLocally(false)

{

  // mOrigin remains at 0,0

}
@@ -33,11 +34,14 @@ StackingContextHelper::StackingContextHelper(const StackingContextHelper& aParen 
                                             const gfx::CompositionOp& aMixBlendMode,

                                             bool aBackfaceVisible,

                                             bool aIsPreserve3D,

                                             const Maybe<gfx::Matrix4x4>& aTransformForScrollData)

                                             const Maybe<gfx::Matrix4x4>& aTransformForScrollData,

                                             const wr::WrClipId* aClipNodeId,

                                             bool aRasterizeLocally)

  : mBuilder(&aBuilder)

  , mScale(1.0f, 1.0f)

  , mTransformForScrollData(aTransformForScrollData)

  , mIsPreserve3D(aIsPreserve3D)

  , mRasterizeLocally(aRasterizeLocally || aParentSC.mRasterizeLocally)

{

  // Compute scale for fallback rendering. We don't try to guess a scale for 3d

  // transformed items
@@ -52,8 +56,12 @@ StackingContextHelper::StackingContextHelper(const StackingContextHelper& aParen 
    mScale = aParentSC.mScale;

  }



  auto rasterSpace = mRasterizeLocally

    ? wr::GlyphRasterSpace::Local(std::max(mScale.width, mScale.height))

    : wr::GlyphRasterSpace::Screen();



  mBuilder->PushStackingContext(wr::ToLayoutRect(aBounds),

                                nullptr,

                                aClipNodeId,

                                aAnimation,

                                aOpacityPtr,

                                aTransformPtr,
@@ -61,7 +69,8 @@ StackingContextHelper::StackingContextHelper(const StackingContextHelper& aParen 
                                aPerspectivePtr,

                                wr::ToMixBlendMode(aMixBlendMode),

                                aFilters,

                                aBackfaceVisible);

                                aBackfaceVisible,

                                rasterSpace);



  mAffectsClipPositioning =

      (aTransformPtr && !aTransformPtr->IsIdentity()) ||

gfx/layers/wr/StackingContextHelper.h

+4 −1
Original line number Diff line number Diff line
@@ -39,7 +39,9 @@ public: 
                        const gfx::CompositionOp& aMixBlendMode = gfx::CompositionOp::OP_OVER,

                        bool aBackfaceVisible = true,

                        bool aIsPreserve3D = false,

                        const Maybe<gfx::Matrix4x4>& aTransformForScrollData = Nothing());

                        const Maybe<gfx::Matrix4x4>& aTransformForScrollData = Nothing(),

                        const wr::WrClipId* aClipNodeId = nullptr,

                        bool aRasterizeLocally = false);

  // This version of the constructor should only be used at the root level

  // of the tree, so that we have a StackingContextHelper to pass down into

  // the RenderLayer traversal, but don't actually want it to push a stacking
@@ -68,6 +70,7 @@ private: 
  bool mAffectsClipPositioning;

  Maybe<gfx::Matrix4x4> mTransformForScrollData;

  bool mIsPreserve3D;

  bool mRasterizeLocally;

};



} // namespace layers

gfx/webrender_bindings/WebRenderAPI.cpp

+8 −4
Original line number Diff line number Diff line
@@ -774,7 +774,8 @@ DisplayListBuilder::PushStackingContext(const wr::LayoutRect& aBounds, 
                                        const gfx::Matrix4x4* aPerspective,

                                        const wr::MixBlendMode& aMixBlendMode,

                                        const nsTArray<wr::WrFilterOp>& aFilters,

                                        bool aIsBackfaceVisible)

                                        bool aIsBackfaceVisible,

                                        const wr::GlyphRasterSpace& aRasterSpace)

{

  wr::LayoutTransform matrix;

  if (aTransform) {
@@ -785,13 +786,16 @@ DisplayListBuilder::PushStackingContext(const wr::LayoutRect& aBounds, 
  if (aPerspective) {

    perspective = ToLayoutTransform(*aPerspective);

  }



  const wr::LayoutTransform* maybePerspective = aPerspective ? &perspective : nullptr;

  const size_t* maybeClipNodeId = aClipNodeId ? &aClipNodeId->id : nullptr;

  WRDL_LOG("PushStackingContext b=%s t=%s\n", mWrState, Stringify(aBounds).c_str(),

      aTransform ? Stringify(*aTransform).c_str() : "none");

  wr_dp_push_stacking_context(mWrState, aBounds, maybeClipNodeId, aAnimation, aOpacity,

                              maybeTransform, aTransformStyle, maybePerspective,

                              aMixBlendMode, aFilters.Elements(), aFilters.Length(), aIsBackfaceVisible);

  wr_dp_push_stacking_context(mWrState, aBounds, maybeClipNodeId, aAnimation,

                              aOpacity, maybeTransform, aTransformStyle,

                              maybePerspective, aMixBlendMode,

                              aFilters.Elements(), aFilters.Length(),

                              aIsBackfaceVisible, aRasterSpace);

}



void

gfx/webrender_bindings/WebRenderAPI.h

+2 −1
Original line number Diff line number Diff line
@@ -266,7 +266,8 @@ public: 
                           const gfx::Matrix4x4* aPerspective,

                           const wr::MixBlendMode& aMixBlendMode,

                           const nsTArray<wr::WrFilterOp>& aFilters,

                           bool aIsBackfaceVisible);

                           bool aIsBackfaceVisible,

                           const wr::GlyphRasterSpace& aRasterSpace);

  void PopStackingContext();



  wr::WrClipId DefineClip(const Maybe<wr::WrScrollId>& aAncestorScrollId,