CurveIntersection.h revision 235f56a92f6eb6accbb243e11b3c45e3798f38f2 
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#ifndef CurveIntersection_DEFINE
8#define CurveIntersection_DEFINE
9
10#include "DataTypes.h"
11
12class Intersections;
13
14// unit-testable utilities
15double axialIntersect(const Quadratic& q1, const _Point& p, bool vert);
16bool bezier_clip(const Cubic& cubic1, const Cubic& cubic2, double& minT, double& maxT);
17bool bezier_clip(const Quadratic& q1, const Quadratic& q2, double& minT, double& maxT);
18void chop_at(const Cubic& src, CubicPair& dst, double t);
19void chop_at(const Quadratic& src, QuadraticPair& dst, double t);
20int convex_hull(const Cubic& cubic, char order[4]);
21bool convex_x_hull(const Cubic& cubic, char connectTo0[2], char connectTo3[2]);
22bool implicit_matches(const Cubic& cubic1, const Cubic& cubic2);
23bool implicit_matches(const _Line& line1, const _Line& line2);
24bool implicit_matches_ulps(const _Line& one, const _Line& two, int ulps);
25bool implicit_matches(const Quadratic& quad1, const Quadratic& quad2);
26void sub_divide(const Cubic& src, double t1, double t2, Cubic& dst);
27void sub_divide(const _Line& src, double t1, double t2, _Line& dst);
28void sub_divide(const Quadratic& src, double t1, double t2, Quadratic& dst);
29void tangent(const Cubic& cubic, double t, _Point& result);
30void tangent(const _Line& line, _Point& result);
31void tangent(const Quadratic& quad, double t, _Point& result);
32
33// main functions
34enum ReduceOrder_Flags {
35    kReduceOrder_NoQuadraticsAllowed,
36    kReduceOrder_QuadraticsAllowed
37};
38int reduceOrder(const Cubic& cubic, Cubic& reduction, ReduceOrder_Flags );
39int reduceOrder(const _Line& line, _Line& reduction);
40int reduceOrder(const Quadratic& quad, Quadratic& reduction);
41int horizontalIntersect(const Cubic& cubic, double y, double tRange[3]);
42int horizontalIntersect(const Cubic& cubic, double left, double right, double y,
43        double tRange[3]);
44int horizontalIntersect(const Cubic& cubic, double left, double right, double y,
45        bool flipped, Intersections&);
46int horizontalIntersect(const _Line& line, double left, double right,
47        double y, bool flipped, Intersections& );
48int horizontalIntersect(const Quadratic& quad, double left, double right,
49        double y, double tRange[2]);
50int horizontalIntersect(const Quadratic& quad, double left, double right,
51        double y, bool flipped, Intersections& );
52bool intersect(const Cubic& cubic1, const Cubic& cubic2, Intersections& );
53int intersect(const Cubic& cubic, const _Line& line, double cRange[3], double lRange[3]);
54bool intersect(const Quadratic& q1, const Quadratic& q2, Intersections& );
55int intersect(const Quadratic& quad, const _Line& line, Intersections& );
56// the following flavor uses the implicit form instead of convex hulls
57bool intersect2(const Quadratic& q1, const Quadratic& q2, Intersections& i);
58int intersectRay(const Quadratic& quad, const _Line& line, Intersections& i);
59
60
61bool isLinear(const Quadratic& quad, int startIndex, int endIndex);
62bool isLinear(const Cubic& cubic, int startIndex, int endIndex);
63double leftMostT(const Cubic& , double startT, double endT);
64double leftMostT(const _Line& , double startT, double endT);
65double leftMostT(const Quadratic& , double startT, double endT);
66int verticalIntersect(const Cubic& cubic, double top, double bottom, double x,
67        bool flipped, Intersections& );
68int verticalIntersect(const _Line& line, double top, double bottom, double x,
69        bool flipped, Intersections& );
70int verticalIntersect(const Quadratic& quad, double top, double bottom,
71        double x, bool flipped, Intersections& );
72
73#endif
74