commit 55abaf5893ae015eab7b6013c133578883de7886
author Chris Dalton <csmartdalton@google.com> Tue Dec 08 10:25:13 2020 -0700
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Thu Dec 10 17:12:38 2020 +0000
tree 8050295c684aa11e5a4a4f58172a21a5cf4d30f8
parent 8655eab56c6c4ed98eed03aba8b173a66146be01

Add a stencil test for transparent tessellated strokes

Initially we restricted tessellated stroking to opaque solid colors.
This CL adds support for transparency by enabling a stencil test. The
stencil test also allows us to use mixed samples.

Bug: skia:10419
Change-Id: Ie40f3099d2b009f92ed49f7f43e5f269b1a479af
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/340798
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

src/gpu/tessellate/GrStrokeOp.h

diff --git a/src/gpu/tessellate/GrStrokeOp.h b/src/gpu/tessellate/GrStrokeOp.h
index ce5d855..7cd4c82 100644
--- a/src/gpu/tessellate/GrStrokeOp.h
+++ b/src/gpu/tessellate/GrStrokeOp.h
@@ -34,10 +34,10 @@
                                       bool hasMixedSampledCoverage, GrClampType) override;
     CombineResult onCombineIfPossible(GrOp*, SkArenaAlloc*, const GrCaps&) override;
 
-    void prePrepareColorProgram(SkArenaAlloc* arena, GrStrokeTessellateShader*,
-                                const GrSurfaceProxyView&, GrAppliedClip&&,
-                                const GrXferProcessor::DstProxyView&, GrXferBarrierFlags,
-                                GrLoadOp colorLoadOp, const GrCaps&);
+    void prePreparePrograms(SkArenaAlloc* arena, GrStrokeTessellateShader*,
+                            const GrSurfaceProxyView&, GrAppliedClip&&,
+                            const GrXferProcessor::DstProxyView&, GrXferBarrierFlags,
+                            GrLoadOp colorLoadOp, const GrCaps&);
 
     static float NumCombinedSegments(float numParametricSegments, float numRadialSegments) {
         // The first and last edges are shared by both the parametric and radial sets of edges, so
@@ -76,12 +76,14 @@
     // smoothness.
     const float fNumRadialSegmentsPerRadian;
     SkPMColor4f fColor;
+    bool fNeedsStencil = false;
     GrProcessorSet fProcessors;
 
     GrSTArenaList<SkPath> fPathList;
     int fTotalCombinedVerbCnt;
 
-    const GrProgramInfo* fColorProgram = nullptr;
+    const GrProgramInfo* fStencilProgram = nullptr;
+    const GrProgramInfo* fFillProgram = nullptr;
 };
 
 #endif