1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2009 Erwin Coumans  http://bulletphysics.org
4 
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages arising from the use of this software.
7 Permission is granted to anyone to use this software for any purpose,
8 including commercial applications, and to alter it and redistribute it freely,
9 subject to the following restrictions:
10 
11 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.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15 #ifndef BT_CONVEX_TRIANGLEMESH_SHAPE_H
16 #define BT_CONVEX_TRIANGLEMESH_SHAPE_H
17 
18 
19 #include "btPolyhedralConvexShape.h"
20 #include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h" // for the types
21 
22 
23 /// The btConvexTriangleMeshShape is a convex hull of a triangle mesh, but the performance is not as good as btConvexHullShape.
24 /// A small benefit of this class is that it uses the btStridingMeshInterface, so you can avoid the duplication of the triangle mesh data. Nevertheless, most users should use the much better performing btConvexHullShape instead.
ATTRIBUTE_ALIGNED16(class)25 ATTRIBUTE_ALIGNED16(class) btConvexTriangleMeshShape : public btPolyhedralConvexAabbCachingShape
26 {
27 
28 	class btStridingMeshInterface*	m_stridingMesh;
29 
30 public:
31 	BT_DECLARE_ALIGNED_ALLOCATOR();
32 
33 	btConvexTriangleMeshShape(btStridingMeshInterface* meshInterface, bool calcAabb = true);
34 
35 	class btStridingMeshInterface*	getMeshInterface()
36 	{
37 		return m_stridingMesh;
38 	}
39 	const class btStridingMeshInterface* getMeshInterface() const
40 	{
41 		return m_stridingMesh;
42 	}
43 
44 	virtual btVector3	localGetSupportingVertex(const btVector3& vec)const;
45 	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
46 	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
47 
48 	//debugging
49 	virtual const char*	getName()const {return "ConvexTrimesh";}
50 
51 	virtual int	getNumVertices() const;
52 	virtual int getNumEdges() const;
53 	virtual void getEdge(int i,btVector3& pa,btVector3& pb) const;
54 	virtual void getVertex(int i,btVector3& vtx) const;
55 	virtual int	getNumPlanes() const;
56 	virtual void getPlane(btVector3& planeNormal,btVector3& planeSupport,int i ) const;
57 	virtual	bool isInside(const btVector3& pt,btScalar tolerance) const;
58 
59 
60 	virtual void	setLocalScaling(const btVector3& scaling);
61 	virtual const btVector3& getLocalScaling() const;
62 
63 	///computes the exact moment of inertia and the transform from the coordinate system defined by the principal axes of the moment of inertia
64 	///and the center of mass to the current coordinate system. A mass of 1 is assumed, for other masses just multiply the computed "inertia"
65 	///by the mass. The resulting transform "principal" has to be applied inversely to the mesh in order for the local coordinate system of the
66 	///shape to be centered at the center of mass and to coincide with the principal axes. This also necessitates a correction of the world transform
67 	///of the collision object by the principal transform. This method also computes the volume of the convex mesh.
68 	void calculatePrincipalAxisTransform(btTransform& principal, btVector3& inertia, btScalar& volume) const;
69 
70 };
71 
72 
73 
74 #endif //BT_CONVEX_TRIANGLEMESH_SHAPE_H
75 
76 
77 
78