121 lines
5.6 KiB
C++
121 lines
5.6 KiB
C++
/********************************************************************************
|
|
* ReactPhysics3D physics library, http://www.reactphysics3d.com *
|
|
* Copyright (c) 2010-2015 Daniel Chappuis *
|
|
*********************************************************************************
|
|
* *
|
|
* 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 REACTPHYSICS3D_GJK_ALGORITHM_H
|
|
#define REACTPHYSICS3D_GJK_ALGORITHM_H
|
|
|
|
// Libraries
|
|
#include "collision/narrowphase/NarrowPhaseAlgorithm.h"
|
|
#include "constraint/ContactPoint.h"
|
|
#include "collision/shapes/ConvexShape.h"
|
|
#include "collision/narrowphase/EPA/EPAAlgorithm.h"
|
|
|
|
|
|
/// ReactPhysics3D namespace
|
|
namespace reactphysics3d {
|
|
|
|
// Constants
|
|
const decimal REL_ERROR = decimal(1.0e-3);
|
|
const decimal REL_ERROR_SQUARE = REL_ERROR * REL_ERROR;
|
|
const int MAX_ITERATIONS_GJK_RAYCAST = 32;
|
|
|
|
// Class GJKAlgorithm
|
|
/**
|
|
* This class implements a narrow-phase collision detection algorithm. This
|
|
* algorithm uses the ISA-GJK algorithm and the EPA algorithm. This
|
|
* implementation is based on the implementation discussed in the book
|
|
* "Collision Detection in Interactive 3D Environments" by Gino van den Bergen.
|
|
* This method implements the Hybrid Technique for calculating the
|
|
* penetration depth. The two objects are enlarged with a small margin. If
|
|
* the object intersects in their margins, the penetration depth is quickly
|
|
* computed using the GJK algorithm on the original objects (without margin).
|
|
* If the original objects (without margin) intersect, we run again the GJK
|
|
* algorithm on the enlarged objects (with margin) to compute simplex
|
|
* polytope that contains the origin and give it to the EPA (Expanding
|
|
* Polytope Algorithm) to compute the correct penetration depth between the
|
|
* enlarged objects.
|
|
*/
|
|
class GJKAlgorithm : public NarrowPhaseAlgorithm {
|
|
|
|
private :
|
|
|
|
// -------------------- Attributes -------------------- //
|
|
|
|
/// EPA Algorithm
|
|
EPAAlgorithm mAlgoEPA;
|
|
|
|
// -------------------- Methods -------------------- //
|
|
|
|
/// Private copy-constructor
|
|
GJKAlgorithm(const GJKAlgorithm& algorithm);
|
|
|
|
/// Private assignment operator
|
|
GJKAlgorithm& operator=(const GJKAlgorithm& algorithm);
|
|
|
|
/// Compute the penetration depth for enlarged objects.
|
|
void computePenetrationDepthForEnlargedObjects(const CollisionShapeInfo& shape1Info,
|
|
const Transform& transform1,
|
|
const CollisionShapeInfo& shape2Info,
|
|
const Transform& transform2,
|
|
NarrowPhaseCallback* narrowPhaseCallback,
|
|
Vector3& v);
|
|
|
|
public :
|
|
|
|
// -------------------- Methods -------------------- //
|
|
|
|
/// Constructor
|
|
GJKAlgorithm();
|
|
|
|
/// Destructor
|
|
~GJKAlgorithm();
|
|
|
|
/// Initalize the algorithm
|
|
virtual void init(CollisionDetection* collisionDetection,
|
|
MemoryAllocator* memoryAllocator);
|
|
|
|
/// Compute a contact info if the two bounding volumes collide.
|
|
virtual void testCollision(const CollisionShapeInfo& shape1Info,
|
|
const CollisionShapeInfo& shape2Info,
|
|
NarrowPhaseCallback* narrowPhaseCallback);
|
|
|
|
/// Use the GJK Algorithm to find if a point is inside a convex collision shape
|
|
bool testPointInside(const Vector3& localPoint, ProxyShape* proxyShape);
|
|
|
|
/// Ray casting algorithm agains a convex collision shape using the GJK Algorithm
|
|
bool raycast(const Ray& ray, ProxyShape* proxyShape, RaycastInfo& raycastInfo);
|
|
};
|
|
|
|
// Initalize the algorithm
|
|
inline void GJKAlgorithm::init(CollisionDetection* collisionDetection,
|
|
MemoryAllocator* memoryAllocator) {
|
|
NarrowPhaseAlgorithm::init(collisionDetection, memoryAllocator);
|
|
mAlgoEPA.init(memoryAllocator);
|
|
}
|
|
|
|
}
|
|
|
|
#endif
|