Bullet Collision Detection & Physics Library
btConvexPointCloudShape.cpp
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1/*
2Bullet Continuous Collision Detection and Physics Library
3Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org
4
5This software is provided 'as-is', without any express or implied warranty.
6In no event will the authors be held liable for any damages arising from the use of this software.
7Permission is granted to anyone to use this software for any purpose,
8including commercial applications, and to alter it and redistribute it freely,
9subject to the following restrictions:
10
111. 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.
122. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
133. This notice may not be removed or altered from any source distribution.
14*/
15
18
20
22{
23 m_localScaling = scaling;
25}
26
27#ifndef __SPU__
29{
30 btVector3 supVec(btScalar(0.), btScalar(0.), btScalar(0.));
32
33 btVector3 vec = vec0;
34 btScalar lenSqr = vec.length2();
35 if (lenSqr < btScalar(0.0001))
36 {
37 vec.setValue(1, 0, 0);
38 }
39 else
40 {
41 btScalar rlen = btScalar(1.) / btSqrt(lenSqr);
42 vec *= rlen;
43 }
44
45 if (m_numPoints > 0)
46 {
47 // Here we take advantage of dot(a*b, c) = dot( a, b*c) to do less work. Note this transformation is true mathematically, not numerically.
48 // btVector3 scaled = vec * m_localScaling;
49 int index = (int)vec.maxDot(&m_unscaledPoints[0], m_numPoints, maxDot); //FIXME: may violate encapsulation of m_unscaledPoints
50 return getScaledPoint(index);
51 }
52
53 return supVec;
54}
55
56void btConvexPointCloudShape::batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors, btVector3* supportVerticesOut, int numVectors) const
57{
58 for (int j = 0; j < numVectors; j++)
59 {
60 const btVector3& vec = vectors[j] * m_localScaling; // dot( a*c, b) = dot(a, b*c)
61 btScalar maxDot;
62 int index = (int)vec.maxDot(&m_unscaledPoints[0], m_numPoints, maxDot);
63 supportVerticesOut[j][3] = btScalar(-BT_LARGE_FLOAT);
64 if (0 <= index)
65 {
66 //WARNING: don't swap next lines, the w component would get overwritten!
67 supportVerticesOut[j] = getScaledPoint(index);
68 supportVerticesOut[j][3] = maxDot;
69 }
70 }
71}
72
74{
76
77 if (getMargin() != btScalar(0.))
78 {
79 btVector3 vecnorm = vec;
80 if (vecnorm.length2() < (SIMD_EPSILON * SIMD_EPSILON))
81 {
82 vecnorm.setValue(btScalar(-1.), btScalar(-1.), btScalar(-1.));
83 }
84 vecnorm.normalize();
85 supVertex += getMargin() * vecnorm;
86 }
87 return supVertex;
88}
89
90#endif
91
92//currently just for debugging (drawing), perhaps future support for algebraic continuous collision detection
93//Please note that you can debug-draw btConvexHullShape with the Raytracer Demo
95{
96 return m_numPoints;
97}
98
100{
101 return 0;
102}
103
105{
106 btAssert(0);
107}
108
110{
112}
113
115{
116 return 0;
117}
118
120{
121 btAssert(0);
122}
123
124//not yet
126{
127 btAssert(0);
128 return false;
129}
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:314
#define BT_LARGE_FLOAT
Definition: btScalar.h:316
btScalar btSqrt(btScalar y)
Definition: btScalar.h:466
#define SIMD_EPSILON
Definition: btScalar.h:543
#define btAssert(x)
Definition: btScalar.h:153
virtual btScalar getMargin() const
virtual btVector3 localGetSupportingVertex(const btVector3 &vec) const
btVector3 getScaledPoint(int index) const
virtual void setLocalScaling(const btVector3 &scaling)
in case we receive negative scaling
virtual void getEdge(int i, btVector3 &pa, btVector3 &pb) const
virtual int getNumVertices() const
virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3 *vectors, btVector3 *supportVerticesOut, int numVectors) const
virtual btVector3 localGetSupportingVertexWithoutMargin(const btVector3 &vec) const
virtual void getVertex(int i, btVector3 &vtx) const
virtual bool isInside(const btVector3 &pt, btScalar tolerance) const
virtual void getPlane(btVector3 &planeNormal, btVector3 &planeSupport, int i) const
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:82
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
long maxDot(const btVector3 *array, long array_count, btScalar &dotOut) const
returns index of maximum dot product between this and vectors in array[]
Definition: btVector3.h:998
btScalar length2() const
Return the length of the vector squared.
Definition: btVector3.h:251
btVector3 & normalize()
Normalize this vector x^2 + y^2 + z^2 = 1.
Definition: btVector3.h:303