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 "SkPathOpsPoint.h" 12 13 struct SkOpCurve; 14 15 struct SkDQuadPair { 16 const SkDQuad& first() const { return (const SkDQuad&) pts[0]; } 17 const SkDQuad& second() const { return (const SkDQuad&) pts[2]; } 18 SkDPoint pts[5]; 19 }; 20 21 struct SkDQuad { 22 static const int kPointCount = 3; 23 static const int kPointLast = kPointCount - 1; 24 static const int kMaxIntersections = 4; 25 26 SkDPoint fPts[kPointCount]; 27 28 bool collapsed() const { 29 return fPts[0].approximatelyEqual(fPts[1]) && fPts[0].approximatelyEqual(fPts[2]); 30 } 31 32 bool controlsInside() const { 33 SkDVector v01 = fPts[0] - fPts[1]; 34 SkDVector v02 = fPts[0] - fPts[2]; 35 SkDVector v12 = fPts[1] - fPts[2]; 36 return v02.dot(v01) > 0 && v02.dot(v12) > 0; 37 } 38 39 void debugInit() { 40 sk_bzero(fPts, sizeof(fPts)); 41 } 42 43 SkDQuad flip() const { 44 SkDQuad result = {{fPts[2], fPts[1], fPts[0]}}; 45 return result; 46 } 47 48 static bool IsConic() { return false; } 49 50 const SkDQuad& set(const SkPoint pts[kPointCount]) { 51 fPts[0] = pts[0]; 52 fPts[1] = pts[1]; 53 fPts[2] = pts[2]; 54 return *this; 55 } 56 57 const SkDPoint& operator[](int n) const { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; } 58 SkDPoint& operator[](int n) { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; } 59 60 static int AddValidTs(double s[], int realRoots, double* t); 61 void align(int endIndex, SkDPoint* dstPt) const; 62 SkDQuadPair chopAt(double t) const; 63 SkDVector dxdyAtT(double t) const; 64 static int FindExtrema(const double src[], double tValue[1]); 65 66 /** 67 * Return the number of valid roots (0 < root < 1) for this cubic intersecting the 68 * specified horizontal line. 69 */ 70 int horizontalIntersect(double yIntercept, double roots[2]) const; 71 72 bool hullIntersects(const SkDQuad& , bool* isLinear) const; 73 bool hullIntersects(const SkDConic& , bool* isLinear) const; 74 bool hullIntersects(const SkDCubic& , bool* isLinear) const; 75 bool isLinear(int startIndex, int endIndex) const; 76 bool monotonicInX() const; 77 bool monotonicInY() const; 78 void otherPts(int oddMan, const SkDPoint* endPt[2]) const; 79 SkDPoint ptAtT(double t) const; 80 static int RootsReal(double A, double B, double C, double t[2]); 81 static int RootsValidT(const double A, const double B, const double C, double s[2]); 82 static void SetABC(const double* quad, double* a, double* b, double* c); 83 SkDQuad subDivide(double t1, double t2) const; 84 static SkDQuad SubDivide(const SkPoint a[kPointCount], double t1, double t2) { 85 SkDQuad quad; 86 quad.set(a); 87 return quad.subDivide(t1, t2); 88 } 89 SkDPoint subDivide(const SkDPoint& a, const SkDPoint& c, double t1, double t2) const; 90 static SkDPoint SubDivide(const SkPoint pts[kPointCount], const SkDPoint& a, const SkDPoint& c, 91 double t1, double t2) { 92 SkDQuad quad; 93 quad.set(pts); 94 return quad.subDivide(a, c, t1, t2); 95 } 96 97 /** 98 * Return the number of valid roots (0 < root < 1) for this cubic intersecting the 99 * specified vertical line. 100 */ 101 int verticalIntersect(double xIntercept, double roots[2]) const; 102 103 SkDCubic debugToCubic() const; 104 // utilities callable by the user from the debugger when the implementation code is linked in 105 void dump() const; 106 void dumpID(int id) const; 107 void dumpInner() const; 108 109 private: 110 // static double Tangent(const double* quadratic, double t); // uncalled 111 }; 112 113 #endif 114
