Minor cleanups for CCPR

Bug: skia:
Change-Id: Ic4838f0e242ded0c3d0cb5c86715ed67d8152f5c
Reviewed-on: https://skia-review.googlesource.com/44520
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>

samplecode/SampleCCPRGeometry.cpp

@@ -29,6 +29,8 @@ using TriangleInstance = GrCCPRCoverageProcessor::TriangleInstance;
 using CurveInstance = GrCCPRCoverageProcessor::CurveInstance;
 using Mode = GrCCPRCoverageProcessor::Mode;
 
+static constexpr float kDebugBloat = 40;
+
 static int num_points(Mode mode)  {
     return mode >= Mode::kSerpentineHulls ? 4 : 3;
 }
@@ -156,10 +158,10 @@ void CCPRGeometryView::onDrawContent(SkCanvas* canvas) {
     gridPaint.setStyle(SkPaint::kStroke_Style);
     gridPaint.setStrokeWidth(0);
     gridPaint.setAntiAlias(true);
-    for (int y = 0; y < this->height(); y += GrCCPRCoverageProcessor::kDebugBloat) {
+    for (int y = 0; y < this->height(); y += kDebugBloat) {
         canvas->drawLine(0, y, this->width(), y, gridPaint);
     }
-    for (int x = 0; x < this->width(); x += GrCCPRCoverageProcessor::kDebugBloat) {
+    for (int x = 0; x < this->width(); x += kDebugBloat) {
         canvas->drawLine(x, 0, x, this->height(), outlinePaint);
     }
 #endif
@@ -220,9 +222,7 @@ void CCPRGeometryView::updateGpuData() {
 
         GrCCPRGeometry geometry;
         geometry.beginContour(fPoints[0]);
-        geometry.cubicTo(fPoints[1], fPoints[2], fPoints[3],
-                         GrCCPRCoverageProcessor::kDebugBloat / 2,
-                         GrCCPRCoverageProcessor::kDebugBloat / 2);
+        geometry.cubicTo(fPoints[1], fPoints[2], fPoints[3], kDebugBloat/2, kDebugBloat/2);
         geometry.endContour();
         fGpuPoints.push_back_n(geometry.points().count(), geometry.points().begin());
         int ptsIdx = 0;
@@ -305,7 +305,7 @@ void CCPRGeometryView::Op::onExecute(GrOpFlushState* state) {
                         SkBlendMode::kSrcOver);
 
     GrCCPRCoverageProcessor ccprProc(fView->fMode, pointsBuffer.get());
-    SkDEBUGCODE(ccprProc.enableDebugVisualizations();)
+    SkDEBUGCODE(ccprProc.enableDebugVisualizations(kDebugBloat);)
 
     GrMesh mesh(4 == vertexCount ?  GrPrimitiveType::kLinesAdjacency : GrPrimitiveType::kTriangles);
     mesh.setInstanced(instanceBuffer.get(), fView->fInstanceCount, 0, vertexCount);

src/core/SkGeometry.h

@@ -166,8 +166,21 @@ enum class SkCubicType {
     kQuadratic,
     kLineOrPoint
 };
-constexpr bool SkCubicIsDegenerate(SkCubicType type) {
-    return type >= SkCubicType::kQuadratic;
+
+static inline bool SkCubicIsDegenerate(SkCubicType type) {
+    switch (type) {
+        case SkCubicType::kSerpentine:
+        case SkCubicType::kLoop:
+        case SkCubicType::kLocalCusp:
+        case SkCubicType::kCuspAtInfinity:
+            return false;
+        default:
+            SK_ABORT("Invalid SkCubicType");
+            // fallthru
+        case SkCubicType::kQuadratic:
+        case SkCubicType::kLineOrPoint:
+            return true;
+    }
 }
 
 /** Returns the cubic classification.

src/gpu/ccpr/GrCCPRCoverageProcessor.cpp

@@ -159,8 +159,8 @@ void PrimitiveProcessor::emitGeometryShader(const GrCCPRCoverageProcessor& proc,
     g->codeAppendf("highp float2 bloat = %f * abs(%s.xz);", kAABloatRadius, rtAdjust);
 
 #ifdef SK_DEBUG
-    if (proc.debugVisualizations()) {
-        g->codeAppendf("bloat *= %f;", GrCCPRCoverageProcessor::kDebugBloat);
+    if (proc.debugVisualizationsEnabled()) {
+        g->codeAppendf("bloat *= %f;", proc.debugBloat());
     }
 #endif
 
@@ -324,7 +324,7 @@ void PrimitiveProcessor::emitCoverage(const GrCCPRCoverageProcessor& proc, GrGLS
     f->codeAppendf("%s = float4(1);", outputCoverage);
 
 #ifdef SK_DEBUG
-    if (proc.debugVisualizations()) {
+    if (proc.debugVisualizationsEnabled()) {
         f->codeAppendf("%s = float4(-%s.a, %s.a, 0, 1);", outputColor, outputColor, outputColor);
     }
 #endif

src/gpu/ccpr/GrCCPRCoverageProcessor.h

@@ -92,12 +92,12 @@ public:
     void getGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder*) const override;
     GrGLSLPrimitiveProcessor* createGLSLInstance(const GrShaderCaps&) const override;
 
-    static constexpr float kDebugBloat = 50;
 #ifdef SK_DEBUG
-    // Increases the 1/2 pixel AA bloat by a factor of kDebugBloat and outputs color instead of
+    // Increases the 1/2 pixel AA bloat by a factor of debugBloat and outputs color instead of
     // coverage (coverage=+1 -> green, coverage=0 -> black, coverage=-1 -> red).
-    void enableDebugVisualizations() { fDebugVisualizations = true; }
-    bool debugVisualizations() const { return fDebugVisualizations; }
+    void enableDebugVisualizations(float debugBloat) { fDebugBloat = debugBloat; }
+    bool debugVisualizationsEnabled() const { return fDebugBloat > 0; }
+    float debugBloat() const { SkASSERT(this->debugVisualizationsEnabled()); return fDebugBloat; }
 
     static void Validate(GrRenderTargetProxy* atlasProxy);
 #endif
@@ -105,10 +105,10 @@ public:
     class PrimitiveProcessor;
 
 private:
-    const Mode         fMode;
-    const Attribute&   fInstanceAttrib;
-    BufferAccess       fPointsBufferAccess;
-    SkDEBUGCODE(bool   fDebugVisualizations = false;)
+    const Mode          fMode;
+    const Attribute&    fInstanceAttrib;
+    BufferAccess        fPointsBufferAccess;
+    SkDEBUGCODE(float   fDebugBloat = false;)
 
     typedef GrGeometryProcessor INHERITED;
 };