Improve caching of dashed paths in GrStencilAndCoverPathRenderer

src/gpu/GrPathRendering.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrPathRendering.h"
 #include "SkDescriptor.h"
 #include "SkGlyph.h"
 #include "SkMatrix.h"
 #include "SkTypeface.h"
 #include "GrPathRange.h"
 
 class GlyphGenerator : public GrPathRange::PathGenerator {
 public:
     GlyphGenerator(const SkTypeface& typeface, const SkDescriptor& desc)
-        : fDesc(desc.copy()),
-          fScalerContext(typeface.createScalerContext(fDesc)) {
+        : fScalerContext(typeface.createScalerContext(&desc))
+#ifdef SK_DEBUG
+        , fDesc(desc.copy())
+#endif
+    {
         fFlipMatrix.setScale(1, -1);
     }
 
     virtual ~GlyphGenerator() {
+#ifdef SK_DEBUG
         SkDescriptor::Free(fDesc);
+#endif
     }
 
     int getNumPaths() override {
         return fScalerContext->getGlyphCount();
     }
 
     void generatePath(int glyphID, SkPath* out) override {
         SkGlyph skGlyph;
         skGlyph.initWithGlyphID(glyphID);
         fScalerContext->getMetrics(&skGlyph);
 
         fScalerContext->getPath(skGlyph, out);
         out->transform(fFlipMatrix); // Load glyphs with the inverted y-direction.
     }
-
+#ifdef SK_DEBUG
     bool isEqualTo(const SkDescriptor& desc) const override {
         return fDesc->equals(desc);
     }
-
+#endif
 private:
-    SkDescriptor* const fDesc;
     const SkAutoTDelete<SkScalerContext> fScalerContext;
     SkMatrix fFlipMatrix;
+#ifdef SK_DEBUG
+    SkDescriptor* const fDesc;
+#endif
 };
 
 GrPathRange* GrPathRendering::createGlyphs(const SkTypeface* typeface,
                                            const SkDescriptor* desc,
-                                           const SkStrokeRec& stroke) {
+                                           const GrStrokeInfo& stroke) {
     if (NULL == typeface) {
         typeface = SkTypeface::GetDefaultTypeface();
         SkASSERT(NULL != typeface);
     }
 
     if (desc) {
         SkAutoTUnref<GlyphGenerator> generator(SkNEW_ARGS(GlyphGenerator, (*typeface, *desc)));
         return this->createPathRange(generator, stroke);
     }
 
     SkScalerContextRec rec;
     memset(&rec, 0, sizeof(rec));
     rec.fFontID = typeface->uniqueID();
     rec.fTextSize = SkPaint::kCanonicalTextSizeForPaths;
     rec.fPreScaleX = rec.fPost2x2[0][0] = rec.fPost2x2[1][1] = SK_Scalar1;
     // Don't bake stroke information into the glyphs, we'll let the GPU do the stroking.
 
     SkAutoDescriptor ad(sizeof(rec) + SkDescriptor::ComputeOverhead(1));
     SkDescriptor*    genericDesc = ad.getDesc();
 
     genericDesc->init();
     genericDesc->addEntry(kRec_SkDescriptorTag, sizeof(rec), &rec);
     genericDesc->computeChecksum();
 
     SkAutoTUnref<GlyphGenerator> generator(SkNEW_ARGS(GlyphGenerator, (*typeface, *genericDesc)));
     return this->createPathRange(generator, stroke);
 }