1 /* 2 * Copyright 2013 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef GrDistanceFieldTextContext_DEFINED 9 #define GrDistanceFieldTextContext_DEFINED 10 11 #include "GrTextContext.h" 12 13 class GrGeometryProcessor; 14 class GrTextStrike; 15 16 /* 17 * This class implements GrTextContext using distance field fonts 18 */ 19 class GrDistanceFieldTextContext : public GrTextContext { 20 public: 21 GrDistanceFieldTextContext(GrContext*, const SkDeviceProperties&, bool enable); 22 virtual ~GrDistanceFieldTextContext(); 23 24 virtual void drawText(const GrPaint&, const SkPaint&, const char text[], size_t byteLength, 25 SkScalar x, SkScalar y) SK_OVERRIDE; 26 virtual void drawPosText(const GrPaint&, const SkPaint&, 27 const char text[], size_t byteLength, 28 const SkScalar pos[], SkScalar constY, 29 int scalarsPerPosition) SK_OVERRIDE; 30 31 virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE; 32 33 private: 34 GrTextStrike* fStrike; 35 SkScalar fTextRatio; 36 bool fUseLCDText; 37 bool fEnableDFRendering; 38 SkAutoTUnref<GrGeometryProcessor> fCachedGeometryProcessor; 39 // Used to check whether fCachedEffect is still valid. 40 uint32_t fEffectTextureUniqueID; 41 SkColor fEffectColor; 42 uint32_t fEffectFlags; 43 GrTexture* fGammaTexture; 44 45 void init(const GrPaint&, const SkPaint&); 46 void drawPackedGlyph(GrGlyph::PackedID, SkFixed left, SkFixed top, GrFontScaler*); 47 void flushGlyphs(); // automatically called by destructor 48 void setupCoverageEffect(const SkColor& filteredColor); 49 void finish(); 50 51 enum { 52 kMinRequestedGlyphs = 1, 53 kDefaultRequestedGlyphs = 64, 54 kMinRequestedVerts = kMinRequestedGlyphs * 4, 55 kDefaultRequestedVerts = kDefaultRequestedGlyphs * 4, 56 }; 57 58 void* fVertices; 59 int32_t fMaxVertices; 60 GrTexture* fCurrTexture; 61 int fCurrVertex; 62 SkRect fVertexBounds; 63 }; 64 65 #endif 66
