godot/core/math/triangulate.h

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/*  triangulate.h                                                         */
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#pragma once

#include "core/math/vector2.h"
#include "core/templates/vector.h"

/*
https://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);
};