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 SkPathOpsCubic_DEFINED 9 #define SkPathOpsCubic_DEFINED 10 11 #include "SkPath.h" 12 #include "SkPathOpsPoint.h" 13 #include "SkTArray.h" 14 15 struct SkDCubicPair { 16 const SkDCubic& first() const { return (const SkDCubic&) pts[0]; } 17 const SkDCubic& second() const { return (const SkDCubic&) pts[3]; } 18 SkDPoint pts[7]; 19 }; 20 21 struct SkDCubic { 22 SkDPoint fPts[4]; 23 24 void set(const SkPoint pts[4]) { 25 fPts[0] = pts[0]; 26 fPts[1] = pts[1]; 27 fPts[2] = pts[2]; 28 fPts[3] = pts[3]; 29 } 30 31 static const int gPrecisionUnit; 32 33 const SkDPoint& operator[](int n) const { SkASSERT(n >= 0 && n < 4); return fPts[n]; } 34 SkDPoint& operator[](int n) { SkASSERT(n >= 0 && n < 4); return fPts[n]; } 35 36 void align(int endIndex, int ctrlIndex, SkDPoint* dstPt) const; 37 double calcPrecision() const; 38 SkDCubicPair chopAt(double t) const; 39 bool clockwise() const; 40 static void Coefficients(const double* cubic, double* A, double* B, double* C, double* D); 41 bool controlsContainedByEnds() const; 42 SkDVector dxdyAtT(double t) const; 43 bool endsAreExtremaInXOrY() const; 44 static int FindExtrema(double a, double b, double c, double d, double tValue[2]); 45 int findInflections(double tValues[]) const; 46 47 static int FindInflections(const SkPoint a[4], double tValues[]) { 48 SkDCubic cubic; 49 cubic.set(a); 50 return cubic.findInflections(tValues); 51 } 52 53 int findMaxCurvature(double tValues[]) const; 54 bool isLinear(int startIndex, int endIndex) const; 55 bool monotonicInY() const; 56 SkDPoint ptAtT(double t) const; 57 static int RootsReal(double A, double B, double C, double D, double t[3]); 58 static int RootsValidT(const double A, const double B, const double C, double D, double s[3]); 59 bool serpentine() const; 60 SkDCubic subDivide(double t1, double t2) const; 61 62 static SkDCubic SubDivide(const SkPoint a[4], double t1, double t2) { 63 SkDCubic cubic; 64 cubic.set(a); 65 return cubic.subDivide(t1, t2); 66 } 67 68 void subDivide(const SkDPoint& a, const SkDPoint& d, double t1, double t2, SkDPoint p[2]) const; 69 70 static void SubDivide(const SkPoint pts[4], const SkDPoint& a, const SkDPoint& d, double t1, 71 double t2, SkDPoint p[2]) { 72 SkDCubic cubic; 73 cubic.set(pts); 74 cubic.subDivide(a, d, t1, t2, p); 75 } 76 77 SkDPoint top(double startT, double endT) const; 78 void toQuadraticTs(double precision, SkTArray<double, true>* ts) const; 79 SkDQuad toQuad() const; 80 }; 81 82 #endif 83
