1 /* 2 * Copyright 2014 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 GrStencilAndCoverTextContext_DEFINED 9 #define GrStencilAndCoverTextContext_DEFINED 10 11 #include "GrTextContext.h" 12 #include "GrDrawState.h" 13 #include "GrDrawTarget.h" 14 #include "SkStrokeRec.h" 15 16 class GrTextStrike; 17 class GrPath; 18 class GrPathRange; 19 20 /* 21 * This class implements text rendering using stencil and cover path rendering 22 * (by the means of GrDrawTarget::drawPath). 23 * This class exposes the functionality through GrTextContext interface. 24 */ 25 class GrStencilAndCoverTextContext : public GrTextContext { 26 public: 27 GrStencilAndCoverTextContext(GrContext*, const SkDeviceProperties&); 28 virtual ~GrStencilAndCoverTextContext(); 29 30 virtual void drawText(const GrPaint&, const SkPaint&, const char text[], 31 size_t byteLength, 32 SkScalar x, SkScalar y) SK_OVERRIDE; 33 virtual void drawPosText(const GrPaint&, const SkPaint&, 34 const char text[], size_t byteLength, 35 const SkScalar pos[], SkScalar constY, 36 int scalarsPerPosition) SK_OVERRIDE; 37 38 virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE; 39 40 private: 41 static const int kGlyphBufferSize = 1024; 42 43 enum RenderMode { 44 /** 45 * This is the render mode used by drawText(), which is mainly used by 46 * the Skia unit tests. It tries match the other text backends exactly, 47 * with the exception of not implementing LCD text, and doing anti- 48 * aliasing with the built-in MSAA. 49 */ 50 kMaxAccuracy_RenderMode, 51 52 /** 53 * This is the render mode used by drawPosText(). It ignores hinting and 54 * LCD text, even if the client provided positions for hinted glyphs, 55 * and renders from a canonically-sized, generic set of paths for the 56 * given typeface. In the future we should work out a system for the 57 * client to know it should not provide hinted glyph positions. This 58 * render mode also tries to use GPU stroking for fake bold, even when 59 * SK_USE_FREETYPE_EMBOLDEN is set. 60 */ 61 kMaxPerformance_RenderMode, 62 }; 63 64 void init(const GrPaint&, const SkPaint&, size_t textByteLength, 65 RenderMode, SkScalar textTranslateY = 0); 66 void initGlyphs(SkGlyphCache* cache); 67 void appendGlyph(uint16_t glyphID, float x); 68 void appendGlyph(uint16_t glyphID, float x, float y); 69 void flush(); 70 void finish(); 71 72 GrDrawState::AutoRestoreEffects fStateRestore; 73 SkScalar fTextRatio; 74 float fTextInverseRatio; 75 SkGlyphCache* fGlyphCache; 76 GrPathRange* fGlyphs; 77 uint32_t fIndexBuffer[kGlyphBufferSize]; 78 float fTransformBuffer[2 * kGlyphBufferSize]; 79 GrDrawTarget::PathTransformType fTransformType; 80 int fPendingGlyphCount; 81 SkMatrix fContextInitialMatrix; 82 bool fNeedsDeviceSpaceGlyphs; 83 }; 84 85 #endif 86