1 | /** |
2 | * Copyright (c) 2006-2023 LOVE Development Team |
3 | * |
4 | * This software is provided 'as-is', without any express or implied |
5 | * warranty. In no event will the authors be held liable for any damages |
6 | * arising from the use of this software. |
7 | * |
8 | * Permission is granted to anyone to use this software for any purpose, |
9 | * including commercial applications, and to alter it and redistribute it |
10 | * freely, subject to the following restrictions: |
11 | * |
12 | * 1. The origin of this software must not be misrepresented; you must not |
13 | * claim that you wrote the original software. If you use this software |
14 | * in a product, an acknowledgment in the product documentation would be |
15 | * appreciated but is not required. |
16 | * 2. Altered source versions must be plainly marked as such, and must not be |
17 | * misrepresented as being the original software. |
18 | * 3. This notice may not be removed or altered from any source distribution. |
19 | **/ |
20 | |
21 | #ifndef LOVE_MATH_BEZIER_CURVE_H |
22 | #define LOVE_MATH_BEZIER_CURVE_H |
23 | |
24 | // LOVE |
25 | #include "common/Object.h" |
26 | #include "common/Vector.h" |
27 | #include <vector> |
28 | |
29 | namespace love |
30 | { |
31 | namespace math |
32 | { |
33 | |
34 | class BezierCurve : public Object |
35 | { |
36 | public: |
37 | |
38 | static love::Type type; |
39 | |
40 | /** |
41 | * @param controlPoints Control polygon of the curve. |
42 | **/ |
43 | BezierCurve(const std::vector<Vector2> &controlPoints); |
44 | |
45 | /** |
46 | * @returns Degree of the curve |
47 | **/ |
48 | size_t getDegree() const |
49 | { |
50 | return controlPoints.size() - 1; |
51 | } |
52 | |
53 | /** |
54 | * @returns First derivative of the curve. |
55 | */ |
56 | BezierCurve getDerivative() const; |
57 | |
58 | /** |
59 | * @returns i'th control point. |
60 | **/ |
61 | const Vector2 &getControlPoint(int i) const; |
62 | |
63 | /** |
64 | * Sets the i'th control point. |
65 | * @param i Control point to change. |
66 | * @param point New control point. |
67 | **/ |
68 | void setControlPoint(int i, const Vector2 &point); |
69 | |
70 | /** |
71 | * Insert a new control point before the i'th control point. |
72 | * If i < 0, Lua string indexing rules apply. |
73 | * @param point Control point to insert. |
74 | * @param pos Position to insert. |
75 | **/ |
76 | void insertControlPoint(const Vector2 &point, int pos = -1); |
77 | |
78 | /** |
79 | * Remove the i'th control point from the curve. |
80 | * @param i Control point to remove |
81 | **/ |
82 | void removeControlPoint(int i); |
83 | |
84 | /** |
85 | * @returns Number of control points. |
86 | **/ |
87 | size_t getControlPointCount() const |
88 | { |
89 | return controlPoints.size(); |
90 | } |
91 | |
92 | /** |
93 | * Move the curve. |
94 | * @param t Translation vector. |
95 | */ |
96 | void translate(const Vector2 &t); |
97 | |
98 | /** |
99 | * Rotate the curve. |
100 | * @param phi Rotation angle (radians). |
101 | * @param center Rotation center. |
102 | */ |
103 | void rotate(double phi, const Vector2 ¢er); |
104 | |
105 | /** |
106 | * Scale the curve. |
107 | * @param phi Scale factor. |
108 | * @param center Scale center. |
109 | */ |
110 | void scale(double phi, const Vector2 ¢er); |
111 | |
112 | /** |
113 | * Evaluates the curve at time t. |
114 | * @param t Curve parameter, must satisfy 0 <= t <= 1. |
115 | **/ |
116 | Vector2 evaluate(double t) const; |
117 | |
118 | /** |
119 | * Get curve segment starting at t1 and ending at t2. |
120 | * The new curve will be parametrized from 0 <= t <= 1. |
121 | * @param t1 Start of the segment. |
122 | * @param t2 End of the segment. |
123 | * @returns Bezier curve covering the segment. |
124 | */ |
125 | BezierCurve* getSegment(double t1, double t2) const; |
126 | |
127 | /** |
128 | * Renders the curve by subdivision. |
129 | * @param accuracy The 'fineness' of the curve. |
130 | * @returns A polygon chain that approximates the bezier curve. |
131 | **/ |
132 | std::vector<Vector2> render(int accuracy = 4) const; |
133 | |
134 | /** |
135 | * Renders a segment of the curve by subdivision. |
136 | * @param start The starting point (between 0 and 1) on the curve. |
137 | * @param end The ending point on the curve. |
138 | * @param accuracy The 'fineness' of the curve. |
139 | * @returns A polygon chain that approximates the segment along the curve |
140 | **/ |
141 | std::vector<Vector2> renderSegment(double start, double end, int accuracy = 4) const; |
142 | |
143 | private: |
144 | std::vector<Vector2> controlPoints; |
145 | }; |
146 | |
147 | } |
148 | } |
149 | |
150 | #endif |
151 | |