113 lines
5.1 KiB
C++
113 lines
5.1 KiB
C++
/*************************************************************************/
|
|
/* convex_hull.h */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* https://godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
|
|
/* Copyright (c) 2014-2021 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. */
|
|
/*************************************************************************/
|
|
|
|
/*
|
|
Copyright (c) 2011 Ole Kniemeyer, MAXON, www.maxon.net
|
|
This software is provided 'as-is', without any express or implied warranty.
|
|
In no event will the authors be held liable for any damages arising from the use of this software.
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it freely,
|
|
subject to the following restrictions:
|
|
1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
|
|
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
*/
|
|
|
|
#ifndef CONVEX_HULL_H
|
|
#define CONVEX_HULL_H
|
|
|
|
#include "core/math/geometry_3d.h"
|
|
#include "core/math/vector3.h"
|
|
#include "core/templates/local_vector.h"
|
|
#include "core/templates/vector.h"
|
|
|
|
/// Convex hull implementation based on Preparata and Hong
|
|
/// See https://code.google.com/p/bullet/issues/detail?id=275
|
|
/// Ole Kniemeyer, MAXON Computer GmbH
|
|
class ConvexHullComputer {
|
|
public:
|
|
class Edge {
|
|
private:
|
|
int32_t next = 0;
|
|
int32_t reverse = 0;
|
|
int32_t target_vertex = 0;
|
|
|
|
friend class ConvexHullComputer;
|
|
|
|
public:
|
|
int32_t get_source_vertex() const {
|
|
return (this + reverse)->target_vertex;
|
|
}
|
|
|
|
int32_t get_target_vertex() const {
|
|
return target_vertex;
|
|
}
|
|
|
|
const Edge *get_next_edge_of_vertex() const // clockwise list of all edges of a vertex
|
|
{
|
|
return this + next;
|
|
}
|
|
|
|
const Edge *get_next_edge_of_face() const // counter-clockwise list of all edges of a face
|
|
{
|
|
return (this + reverse)->get_next_edge_of_vertex();
|
|
}
|
|
|
|
const Edge *get_reverse_edge() const {
|
|
return this + reverse;
|
|
}
|
|
};
|
|
|
|
// Vertices of the output hull
|
|
Vector<Vector3> vertices;
|
|
|
|
// Edges of the output hull
|
|
LocalVector<Edge> edges;
|
|
|
|
// Faces of the convex hull. Each entry is an index into the "edges" array pointing to an edge of the face. Faces are planar n-gons
|
|
LocalVector<int32_t> faces;
|
|
|
|
/*
|
|
Compute convex hull of "count" vertices stored in "coords".
|
|
If "shrink" is positive, the convex hull is shrunken by that amount (each face is moved by "shrink" length units
|
|
towards the center along its normal).
|
|
If "shrinkClamp" is positive, "shrink" is clamped to not exceed "shrinkClamp * innerRadius", where "innerRadius"
|
|
is the minimum distance of a face to the center of the convex hull.
|
|
The returned value is the amount by which the hull has been shrunken. If it is negative, the amount was so large
|
|
that the resulting convex hull is empty.
|
|
The output convex hull can be found in the member variables "vertices", "edges", "faces".
|
|
*/
|
|
real_t compute(const Vector3 *p_coords, int32_t p_count, real_t p_shrink, real_t p_shrink_clamp);
|
|
|
|
static Error convex_hull(const Vector<Vector3> &p_points, Geometry3D::MeshData &r_mesh);
|
|
};
|
|
|
|
#endif // CONVEX_HULL_H
|