virtualx-engine/core/math/quick_hull.h

/*************************************************************************/
/*  quick_hull.h                                                         */
/*************************************************************************/
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/*                           GODOT ENGINE                                */
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/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
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#ifndef QUICK_HULL_H
#define QUICK_HULL_H

#include "core/list.h"
#include "core/math/aabb.h"
#include "core/math/geometry.h"
#include "core/set.h"

class QuickHull {
public:
	struct Edge {
		union {
			uint32_t vertices[2];
			uint64_t id;
		};

		bool operator<(const Edge &p_edge) const {
			return id < p_edge.id;
		}

		Edge(int p_vtx_a = 0, int p_vtx_b = 0) {
			if (p_vtx_a > p_vtx_b) {
				SWAP(p_vtx_a, p_vtx_b);
			}

			vertices[0] = p_vtx_a;
			vertices[1] = p_vtx_b;
		}
	};

	struct Face {
		Plane plane;
		uint32_t vertices[3];
		Vector<int> points_over;

		bool operator<(const Face &p_face) const {
			return points_over.size() < p_face.points_over.size();
		}
	};

private:
	struct FaceConnect {
		List<Face>::Element *left, *right;
		FaceConnect() {
			left = nullptr;
			right = nullptr;
		}
	};
	struct RetFaceConnect {
		List<Geometry::MeshData::Face>::Element *left, *right;
		RetFaceConnect() {
			left = nullptr;
			right = nullptr;
		}
	};

public:
	static uint32_t debug_stop_after;
	static Error build(const Vector<Vector3> &p_points, Geometry::MeshData &r_mesh);
};

#endif // QUICK_HULL_H