summaryrefslogtreecommitdiff
path: root/core/math/triangulate.h
blob: c453b77ecf5d98d2cff4292c900c502bc54bfc65 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
/*************************************************************************/
/*  triangulate.h                                                        */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/

#ifndef TRIANGULATE_H
#define TRIANGULATE_H

#include "core/math/vector2.h"

/*
http://www.flipcode.com/archives/Efficient_Polygon_Triangulation.shtml
*/

class Triangulate {
public:
	// triangulate a contour/polygon, places results in STL vector
	// as series of triangles.
	static bool triangulate(const Vector<Vector2> &contour, Vector<int> &result);

	// compute area of a contour/polygon
	static real_t get_area(const Vector<Vector2> &contour);

	// decide if point Px/Py is inside triangle defined by
	// (Ax,Ay) (Bx,By) (Cx,Cy)
	static bool is_inside_triangle(real_t Ax, real_t Ay,
			real_t Bx, real_t By,
			real_t Cx, real_t Cy,
			real_t Px, real_t Py,
			bool include_edges);

private:
	static bool snip(const Vector<Vector2> &p_contour, int u, int v, int w, int n, const Vector<int> &V, bool relaxed);
};

#endif // TRIANGULATE_H