/*************************************************************************/
/*  triangle_mesh.h                                                      */
/*************************************************************************/
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#ifndef TRIANGLE_MESH_H
#define TRIANGLE_MESH_H

#include "core/math/face3.h"
#include "core/object/ref_counted.h"

class TriangleMesh : public RefCounted {
	GDCLASS(TriangleMesh, RefCounted);

public:
	struct Triangle {
		Vector3 normal;
		int indices[3];
	};

private:
	Vector<Triangle> triangles;
	Vector<Vector3> vertices;

	struct BVH {
		AABB aabb;
		Vector3 center; //used for sorting
		int left;
		int right;

		int face_index;
	};

	struct BVHCmpX {
		bool operator()(const BVH *p_left, const BVH *p_right) const {
			return p_left->center.x < p_right->center.x;
		}
	};

	struct BVHCmpY {
		bool operator()(const BVH *p_left, const BVH *p_right) const {
			return p_left->center.y < p_right->center.y;
		}
	};
	struct BVHCmpZ {
		bool operator()(const BVH *p_left, const BVH *p_right) const {
			return p_left->center.z < p_right->center.z;
		}
	};

	int _create_bvh(BVH *p_bvh, BVH **p_bb, int p_from, int p_size, int p_depth, int &max_depth, int &max_alloc);

	Vector<BVH> bvh;
	int max_depth;
	bool valid;

public:
	bool is_valid() const;
	bool intersect_segment(const Vector3 &p_begin, const Vector3 &p_end, Vector3 &r_point, Vector3 &r_normal) const;
	bool intersect_ray(const Vector3 &p_begin, const Vector3 &p_dir, Vector3 &r_point, Vector3 &r_normal) const;
	bool intersect_convex_shape(const Plane *p_planes, int p_plane_count, const Vector3 *p_points, int p_point_count) const;
	bool inside_convex_shape(const Plane *p_planes, int p_plane_count, const Vector3 *p_points, int p_point_count, Vector3 p_scale = Vector3(1, 1, 1)) const;
	Vector3 get_area_normal(const AABB &p_aabb) const;
	Vector<Face3> get_faces() const;

	const Vector<Triangle> &get_triangles() const { return triangles; }
	const Vector<Vector3> &get_vertices() const { return vertices; }
	void get_indices(Vector<int> *r_triangles_indices) const;

	void create(const Vector<Vector3> &p_faces);
	TriangleMesh();
};

#endif // TRIANGLE_MESH_H