1 /* 2 * Copyright 2012 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 SkPathOpsQuad_DEFINED 9 #define SkPathOpsQuad_DEFINED 10 11 #include "SkArenaAlloc.h" 12 #include "SkPathOpsTCurve.h" 13 14 struct SkOpCurve; 15 16 struct SkDQuadPair { 17 const SkDQuad& first() const { return (const SkDQuad&) pts[0]; } 18 const SkDQuad& second() const { return (const SkDQuad&) pts[2]; } 19 SkDPoint pts[5]; 20 }; 21 22 struct SkDQuad { 23 static const int kPointCount = 3; 24 static const int kPointLast = kPointCount - 1; 25 static const int kMaxIntersections = 4; 26 27 SkDPoint fPts[kPointCount]; 28 29 bool collapsed() const { 30 return fPts[0].approximatelyEqual(fPts[1]) && fPts[0].approximatelyEqual(fPts[2]); 31 } 32 33 bool controlsInside() const { 34 SkDVector v01 = fPts[0] - fPts[1]; 35 SkDVector v02 = fPts[0] - fPts[2]; 36 SkDVector v12 = fPts[1] - fPts[2]; 37 return v02.dot(v01) > 0 && v02.dot(v12) > 0; 38 } 39 40 void debugInit() { 41 sk_bzero(fPts, sizeof(fPts)); 42 } 43 44 void debugSet(const SkDPoint* pts); 45 46 SkDQuad flip() const { 47 SkDQuad result = {{fPts[2], fPts[1], fPts[0]} SkDEBUGPARAMS(fDebugGlobalState) }; 48 return result; 49 } 50 51 static bool IsConic() { return false; } 52 53 const SkDQuad& set(const SkPoint pts[kPointCount] 54 SkDEBUGPARAMS(SkOpGlobalState* state = nullptr)) { 55 fPts[0] = pts[0]; 56 fPts[1] = pts[1]; 57 fPts[2] = pts[2]; 58 SkDEBUGCODE(fDebugGlobalState = state); 59 return *this; 60 } 61 62 const SkDPoint& operator[](int n) const { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; } 63 SkDPoint& operator[](int n) { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; } 64 65 static int AddValidTs(double s[], int realRoots, double* t); 66 void align(int endIndex, SkDPoint* dstPt) const; 67 SkDQuadPair chopAt(double t) const; 68 SkDVector dxdyAtT(double t) const; 69 static int FindExtrema(const double src[], double tValue[1]); 70 71 #ifdef SK_DEBUG 72 SkOpGlobalState* globalState() const { return fDebugGlobalState; } 73 #endif 74 75 /** 76 * Return the number of valid roots (0 < root < 1) for this cubic intersecting the 77 * specified horizontal line. 78 */ 79 int horizontalIntersect(double yIntercept, double roots[2]) const; 80 81 bool hullIntersects(const SkDQuad& , bool* isLinear) const; 82 bool hullIntersects(const SkDConic& , bool* isLinear) const; 83 bool hullIntersects(const SkDCubic& , bool* isLinear) const; 84 bool isLinear(int startIndex, int endIndex) const; 85 static int maxIntersections() { return kMaxIntersections; } 86 bool monotonicInX() const; 87 bool monotonicInY() const; 88 void otherPts(int oddMan, const SkDPoint* endPt[2]) const; 89 static int pointCount() { return kPointCount; } 90 static int pointLast() { return kPointLast; } 91 SkDPoint ptAtT(double t) const; 92 static int RootsReal(double A, double B, double C, double t[2]); 93 static int RootsValidT(const double A, const double B, const double C, double s[2]); 94 static void SetABC(const double* quad, double* a, double* b, double* c); 95 SkDQuad subDivide(double t1, double t2) const; 96 void subDivide(double t1, double t2, SkDQuad* quad) const { *quad = this->subDivide(t1, t2); } 97 98 static SkDQuad SubDivide(const SkPoint a[kPointCount], double t1, double t2) { 99 SkDQuad quad; 100 quad.set(a); 101 return quad.subDivide(t1, t2); 102 } 103 SkDPoint subDivide(const SkDPoint& a, const SkDPoint& c, double t1, double t2) const; 104 static SkDPoint SubDivide(const SkPoint pts[kPointCount], const SkDPoint& a, const SkDPoint& c, 105 double t1, double t2) { 106 SkDQuad quad; 107 quad.set(pts); 108 return quad.subDivide(a, c, t1, t2); 109 } 110 111 /** 112 * Return the number of valid roots (0 < root < 1) for this cubic intersecting the 113 * specified vertical line. 114 */ 115 int verticalIntersect(double xIntercept, double roots[2]) const; 116 117 SkDCubic debugToCubic() const; 118 // utilities callable by the user from the debugger when the implementation code is linked in 119 void dump() const; 120 void dumpID(int id) const; 121 void dumpInner() const; 122 123 SkDEBUGCODE(SkOpGlobalState* fDebugGlobalState); 124 }; 125 126 127 class SkTQuad : public SkTCurve { 128 public: 129 SkDQuad fQuad; 130 131 SkTQuad() {} 132 133 SkTQuad(const SkDQuad& q) 134 : fQuad(q) { 135 } 136 137 ~SkTQuad() override {} 138 139 const SkDPoint& operator[](int n) const override { return fQuad[n]; } 140 SkDPoint& operator[](int n) override { return fQuad[n]; } 141 142 bool collapsed() const override { return fQuad.collapsed(); } 143 bool controlsInside() const override { return fQuad.controlsInside(); } 144 void debugInit() override { return fQuad.debugInit(); } 145 #if DEBUG_T_SECT 146 void dumpID(int id) const override { return fQuad.dumpID(id); } 147 #endif 148 SkDVector dxdyAtT(double t) const override { return fQuad.dxdyAtT(t); } 149 #ifdef SK_DEBUG 150 SkOpGlobalState* globalState() const override { return fQuad.globalState(); } 151 #endif 152 153 bool hullIntersects(const SkDQuad& quad, bool* isLinear) const override { 154 return quad.hullIntersects(fQuad, isLinear); 155 } 156 157 bool hullIntersects(const SkDConic& conic, bool* isLinear) const override; 158 bool hullIntersects(const SkDCubic& cubic, bool* isLinear) const override; 159 160 bool hullIntersects(const SkTCurve& curve, bool* isLinear) const override { 161 return curve.hullIntersects(fQuad, isLinear); 162 } 163 164 int intersectRay(SkIntersections* i, const SkDLine& line) const override; 165 bool IsConic() const override { return false; } 166 SkTCurve* make(SkArenaAlloc& heap) const override { return heap.make<SkTQuad>(); } 167 168 int maxIntersections() const override { return SkDQuad::kMaxIntersections; } 169 170 void otherPts(int oddMan, const SkDPoint* endPt[2]) const override { 171 fQuad.otherPts(oddMan, endPt); 172 } 173 174 int pointCount() const override { return SkDQuad::kPointCount; } 175 int pointLast() const override { return SkDQuad::kPointLast; } 176 SkDPoint ptAtT(double t) const override { return fQuad.ptAtT(t); } 177 void setBounds(SkDRect* ) const override; 178 179 void subDivide(double t1, double t2, SkTCurve* curve) const override { 180 ((SkTQuad*) curve)->fQuad = fQuad.subDivide(t1, t2); 181 } 182 }; 183 184 #endif 185
