Bullet Collision Detection & Physics Library: btConvexPointCloudShape.cpp Source File

Bullet Collision Detection & Physics Library

btConvexPointCloudShape.cpp
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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
16 #include "btConvexPointCloudShape.h"
17 #include "BulletCollision/CollisionShapes/btCollisionMargin.h"
18
19 #include "LinearMath/btQuaternion.h"
20
21 void btConvexPointCloudShape::setLocalScaling(const btVector3& scaling)
22 {
23 m_localScaling = scaling;
24 recalcLocalAabb();
25 }
26
27 #ifndef __SPU__
28 btVector3 btConvexPointCloudShape::localGetSupportingVertexWithoutMargin(const btVector3& vec0) const
29 {
30 btVector3 supVec(btScalar(0.), btScalar(0.), btScalar(0.));
31 btScalar maxDot = btScalar(-BT_LARGE_FLOAT);
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
56 void 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
73 btVector3 btConvexPointCloudShape::localGetSupportingVertex(const btVector3& vec) const
74 {
75 btVector3 supVertex = localGetSupportingVertexWithoutMargin(vec);
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
94 int btConvexPointCloudShape::getNumVertices() const
95 {
96 return m_numPoints;
97 }
98
99 int btConvexPointCloudShape::getNumEdges() const
100 {
101 return 0;
102 }
103
104 void btConvexPointCloudShape::getEdge(int i, btVector3& pa, btVector3& pb) const
105 {
106 btAssert(0);
107 }
108
109 void btConvexPointCloudShape::getVertex(int i, btVector3& vtx) const
110 {
111 vtx = m_unscaledPoints[i] * m_localScaling;
112 }
113
114 int btConvexPointCloudShape::getNumPlanes() const
115 {
116 return 0;
117 }
118
119 void btConvexPointCloudShape::getPlane(btVector3&, btVector3&, int) const
120 {
121 btAssert(0);
122 }
123
124 //not yet
125 bool btConvexPointCloudShape::isInside(const btVector3&, btScalar) const
126 {
127 btAssert(0);
128 return false;
129 }
SIMD_EPSILON
#define SIMD_EPSILON
Definition: btScalar.h:523
btConvexPointCloudShape::getScaledPoint
btVector3 getScaledPoint(int index) const
Definition: btConvexPointCloudShape.h:77
BT_LARGE_FLOAT
#define BT_LARGE_FLOAT
Definition: btScalar.h:296
btVector3::setValue
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
btConvexPointCloudShape::getNumEdges
virtual int getNumEdges() const
Definition: btConvexPointCloudShape.cpp:99
btConvexPointCloudShape::getEdge
virtual void getEdge(int i, btVector3 &pa, btVector3 &pb) const
Definition: btConvexPointCloudShape.cpp:104
btVector3::length2
btScalar length2() const
Return the length of the vector squared.
Definition: btVector3.h:251
btSqrt
btScalar btSqrt(btScalar y)
Definition: btScalar.h:446
btAssert
#define btAssert(x)
Definition: btScalar.h:133
btConvexPointCloudShape::setLocalScaling
virtual void setLocalScaling(const btVector3 &scaling)
in case we receive negative scaling
Definition: btConvexPointCloudShape.cpp:21
btConvexInternalShape::m_localScaling
btVector3 m_localScaling
Definition: btConvexInternalShape.h:33
btConvexPointCloudShape::batchedUnitVectorGetSupportingVertexWithoutMargin
virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3 *vectors, btVector3 *supportVerticesOut, int numVectors) const
Definition: btConvexPointCloudShape.cpp:56
btConvexPointCloudShape::getNumPlanes
virtual int getNumPlanes() const
Definition: btConvexPointCloudShape.cpp:114
btCollisionMargin.h
btVector3::normalize
btVector3 & normalize()
Normalize this vector x^2 + y^2 + z^2 = 1.
Definition: btVector3.h:303
btVector3::maxDot
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
btConvexPointCloudShape::getVertex
virtual void getVertex(int i, btVector3 &vtx) const
Definition: btConvexPointCloudShape.cpp:109
btConvexPointCloudShape::getPlane
virtual void getPlane(btVector3 &planeNormal, btVector3 &planeSupport, int i) const
Definition: btConvexPointCloudShape.cpp:119
btQuaternion.h
btConvexInternalShape::getMargin
virtual btScalar getMargin() const
Definition: btConvexInternalShape.h:106
btConvexPointCloudShape::isInside
virtual bool isInside(const btVector3 &pt, btScalar tolerance) const
Definition: btConvexPointCloudShape.cpp:125
btConvexPointCloudShape.h
btConvexPointCloudShape::getNumVertices
virtual int getNumVertices() const
Definition: btConvexPointCloudShape.cpp:94
btConvexPointCloudShape::m_unscaledPoints
btVector3 * m_unscaledPoints
Definition: btConvexPointCloudShape.h:27
btVector3
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:80
btConvexPointCloudShape::m_numPoints
int m_numPoints
Definition: btConvexPointCloudShape.h:28
btConvexPointCloudShape::localGetSupportingVertex
virtual btVector3 localGetSupportingVertex(const btVector3 &vec) const
Definition: btConvexPointCloudShape.cpp:73
btConvexPointCloudShape::localGetSupportingVertexWithoutMargin
virtual btVector3 localGetSupportingVertexWithoutMargin(const btVector3 &vec) const
Definition: btConvexPointCloudShape.cpp:28
btPolyhedralConvexAabbCachingShape::recalcLocalAabb
void recalcLocalAabb()
Definition: btPolyhedralConvexShape.cpp:505
btScalar
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:294