1 /* 2 * Copyright 2017 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 SkAtlasTextTarget_DEFINED 9 #define SkAtlasTextTarget_DEFINED 10 11 #include <memory> 12 #include "SkDeque.h" 13 #include "SkRefCnt.h" 14 #include "SkScalar.h" 15 16 class SkAtlasTextContext; 17 class SkAtlasTextFont; 18 class SkMatrix; 19 struct SkPoint; 20 21 /** Represents a client-created renderable surface and is used to draw text into the surface. */ 22 class SK_API SkAtlasTextTarget { 23 public: 24 virtual ~SkAtlasTextTarget(); 25 26 /** 27 * Creates a text drawing target. ‘handle’ is used to identify this rendering surface when 28 * draws are flushed to the SkAtlasTextContext's SkAtlasTextRenderer. 29 */ 30 static std::unique_ptr<SkAtlasTextTarget> Make(sk_sp<SkAtlasTextContext>, int width, int height, 31 void* handle); 32 33 /** 34 * Enqueues a text draw in the target. The caller provides an array of glyphs and their 35 * positions. The meaning of 'color' here is interpreted by the client's SkAtlasTextRenderer 36 * when it actually renders the text. 37 */ 38 virtual void drawText(const SkGlyphID[], const SkPoint[], int glyphCnt, uint32_t color, 39 const SkAtlasTextFont&) = 0; 40 41 /** Issues all queued text draws to SkAtlasTextRenderer. */ 42 virtual void flush() = 0; 43 width()44 int width() const { return fWidth; } height()45 int height() const { return fHeight; } 46 handle()47 void* handle() const { return fHandle; } 48 context()49 SkAtlasTextContext* context() const { return fContext.get(); } 50 51 /** Saves the current matrix in a stack. Returns the prior depth of the saved matrix stack. */ 52 int save(); 53 /** Pops the top matrix on the stack if the stack is not empty. */ 54 void restore(); 55 /** 56 * Pops the matrix stack until the stack depth is count. Does nothing if the depth is already 57 * less than count. 58 */ 59 void restoreToCount(int count); 60 61 /** Pre-translates the current CTM. */ 62 void translate(SkScalar dx, SkScalar dy); 63 /** Pre-scales the current CTM. */ 64 void scale(SkScalar sx, SkScalar sy); 65 /** Pre-rotates the current CTM about the origin. */ 66 void rotate(SkScalar degrees); 67 /** Pre-rotates the current CTM about the (px, py). */ 68 void rotate(SkScalar degrees, SkScalar px, SkScalar py); 69 /** Pre-skews the current CTM. */ 70 void skew(SkScalar sx, SkScalar sy); 71 /** Pre-concats the current CTM. */ 72 void concat(const SkMatrix& matrix); 73 74 protected: 75 SkAtlasTextTarget(sk_sp<SkAtlasTextContext>, int width, int height, void* handle); 76 ctm()77 const SkMatrix& ctm() const { return *static_cast<const SkMatrix*>(fMatrixStack.back()); } 78 79 void* const fHandle; 80 const sk_sp<SkAtlasTextContext> fContext; 81 const int fWidth; 82 const int fHeight; 83 84 private: 85 SkDeque fMatrixStack; 86 int fSaveCnt; 87 accessCTM()88 SkMatrix* accessCTM() const { 89 return static_cast<SkMatrix*>(const_cast<void*>(fMatrixStack.back())); 90 } 91 92 SkAtlasTextTarget() = delete; 93 SkAtlasTextTarget(const SkAtlasTextContext&) = delete; 94 SkAtlasTextTarget& operator=(const SkAtlasTextContext&) = delete; 95 }; 96 97 #endif 98