1 2 /* 3 * Copyright 2006 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #ifndef SkEdge_DEFINED 11 #define SkEdge_DEFINED 12 13 #include "SkRect.h" 14 15 struct SkEdge { 16 enum Type { 17 kLine_Type, 18 kQuad_Type, 19 kCubic_Type 20 }; 21 22 SkEdge* fNext; 23 SkEdge* fPrev; 24 25 SkFixed fX; 26 SkFixed fDX; 27 int32_t fFirstY; 28 int32_t fLastY; 29 int8_t fCurveCount; // only used by kQuad(+) and kCubic(-) 30 uint8_t fCurveShift; // appled to all Dx/DDx/DDDx except for fCubicDShift exception 31 uint8_t fCubicDShift; // applied to fCDx and fCDy only in cubic 32 int8_t fWinding; // 1 or -1 33 34 int setLine(const SkPoint& p0, const SkPoint& p1, const SkIRect* clip, 35 int shiftUp); 36 inline int updateLine(SkFixed ax, SkFixed ay, SkFixed bx, SkFixed by); 37 void chopLineWithClip(const SkIRect& clip); 38 intersectsClipSkEdge39 inline bool intersectsClip(const SkIRect& clip) const { 40 SkASSERT(fFirstY < clip.fBottom); 41 return fLastY >= clip.fTop; 42 } 43 44 #ifdef SK_DEBUG dumpSkEdge45 void dump() const { 46 #ifdef SK_CAN_USE_FLOAT 47 SkDebugf("edge: firstY:%d lastY:%d x:%g dx:%g w:%d\n", fFirstY, fLastY, SkFixedToFloat(fX), SkFixedToFloat(fDX), fWinding); 48 #else 49 SkDebugf("edge: firstY:%d lastY:%d x:%x dx:%x w:%d\n", fFirstY, fLastY, fX, fDX, fWinding); 50 #endif 51 } 52 validateSkEdge53 void validate() const { 54 SkASSERT(fPrev && fNext); 55 SkASSERT(fPrev->fNext == this); 56 SkASSERT(fNext->fPrev == this); 57 58 SkASSERT(fFirstY <= fLastY); 59 SkASSERT(SkAbs32(fWinding) == 1); 60 } 61 #endif 62 }; 63 64 struct SkQuadraticEdge : public SkEdge { 65 SkFixed fQx, fQy; 66 SkFixed fQDx, fQDy; 67 SkFixed fQDDx, fQDDy; 68 SkFixed fQLastX, fQLastY; 69 70 int setQuadratic(const SkPoint pts[3], int shiftUp); 71 int updateQuadratic(); 72 }; 73 74 struct SkCubicEdge : public SkEdge { 75 SkFixed fCx, fCy; 76 SkFixed fCDx, fCDy; 77 SkFixed fCDDx, fCDDy; 78 SkFixed fCDDDx, fCDDDy; 79 SkFixed fCLastX, fCLastY; 80 81 int setCubic(const SkPoint pts[4], const SkIRect* clip, int shiftUp); 82 int updateCubic(); 83 }; 84 85 #endif 86