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

Bullet Collision Detection & Physics Library

btManifoldResult.cpp
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1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
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
17 #include "btManifoldResult.h"
18 #include "BulletCollision/NarrowPhaseCollision/btPersistentManifold.h"
19 #include "BulletCollision/CollisionDispatch/btCollisionObject.h"
20 #include "BulletCollision/CollisionDispatch/btCollisionObjectWrapper.h"
21
23 ContactAddedCallback gContactAddedCallback=0;
24
25
26
27 btScalar btManifoldResult::calculateCombinedRollingFriction(const btCollisionObject* body0,const btCollisionObject* body1)
28 {
29 btScalar friction = body0->getRollingFriction() * body1->getFriction() + body1->getRollingFriction() * body0->getFriction();
30
31 const btScalar MAX_FRICTION = btScalar(10.);
32 if (friction < -MAX_FRICTION)
33 friction = -MAX_FRICTION;
34 if (friction > MAX_FRICTION)
35 friction = MAX_FRICTION;
36 return friction;
37
38 }
39
40 btScalar btManifoldResult::calculateCombinedSpinningFriction(const btCollisionObject* body0,const btCollisionObject* body1)
41 {
42 btScalar friction = body0->getSpinningFriction() * body1->getFriction() + body1->getSpinningFriction() * body0->getFriction();
43
44 const btScalar MAX_FRICTION = btScalar(10.);
45 if (friction < -MAX_FRICTION)
46 friction = -MAX_FRICTION;
47 if (friction > MAX_FRICTION)
48 friction = MAX_FRICTION;
49 return friction;
50 }
51
53 btScalar btManifoldResult::calculateCombinedFriction(const btCollisionObject* body0,const btCollisionObject* body1)
54 {
55 btScalar friction = body0->getFriction() * body1->getFriction();
56
57 const btScalar MAX_FRICTION = btScalar(10.);
58 if (friction < -MAX_FRICTION)
59 friction = -MAX_FRICTION;
60 if (friction > MAX_FRICTION)
61 friction = MAX_FRICTION;
62 return friction;
63
64 }
65
66 btScalar btManifoldResult::calculateCombinedRestitution(const btCollisionObject* body0,const btCollisionObject* body1)
67 {
68 return body0->getRestitution() * body1->getRestitution();
69 }
70
71 btScalar btManifoldResult::calculateCombinedContactDamping(const btCollisionObject* body0,const btCollisionObject* body1)
72 {
73 return body0->getContactDamping() + body1->getContactDamping();
74 }
75
76 btScalar btManifoldResult::calculateCombinedContactStiffness(const btCollisionObject* body0,const btCollisionObject* body1)
77 {
78
79 btScalar s0 = body0->getContactStiffness();
80 btScalar s1 = body1->getContactStiffness();
81
82 btScalar tmp0 = btScalar(1)/s0;
83 btScalar tmp1 = btScalar(1)/s1;
84 btScalar combinedStiffness = btScalar(1) / (tmp0+tmp1);
85 return combinedStiffness;
86 }
87
88
89 btManifoldResult::btManifoldResult(const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap)
90 :m_manifoldPtr(0),
91 m_body0Wrap(body0Wrap),
92 m_body1Wrap(body1Wrap)
93 #ifdef DEBUG_PART_INDEX
94 ,m_partId0(-1),
95 m_partId1(-1),
96 m_index0(-1),
97 m_index1(-1)
98 #endif //DEBUG_PART_INDEX
99 , m_closestPointDistanceThreshold(0)
100 {
101 }
102
103
104 void btManifoldResult::addContactPoint(const btVector3& normalOnBInWorld,const btVector3& pointInWorld,btScalar depth)
105 {
106 btAssert(m_manifoldPtr);
107 //order in manifold needs to match
108
109 if (depth > m_manifoldPtr->getContactBreakingThreshold())
110 // if (depth > m_manifoldPtr->getContactProcessingThreshold())
111 return;
112
113 bool isSwapped = m_manifoldPtr->getBody0() != m_body0Wrap->getCollisionObject();
114 bool isNewCollision = m_manifoldPtr->getNumContacts() == 0;
115
116 btVector3 pointA = pointInWorld + normalOnBInWorld * depth;
117
118 btVector3 localA;
119 btVector3 localB;
120
121 if (isSwapped)
122 {
123 localA = m_body1Wrap->getCollisionObject()->getWorldTransform().invXform(pointA );
124 localB = m_body0Wrap->getCollisionObject()->getWorldTransform().invXform(pointInWorld);
125 } else
126 {
127 localA = m_body0Wrap->getCollisionObject()->getWorldTransform().invXform(pointA );
128 localB = m_body1Wrap->getCollisionObject()->getWorldTransform().invXform(pointInWorld);
129 }
130
131 btManifoldPoint newPt(localA,localB,normalOnBInWorld,depth);
132 newPt.m_positionWorldOnA = pointA;
133 newPt.m_positionWorldOnB = pointInWorld;
134
135 int insertIndex = m_manifoldPtr->getCacheEntry(newPt);
136
137 newPt.m_combinedFriction = calculateCombinedFriction(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
138 newPt.m_combinedRestitution = calculateCombinedRestitution(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
139 newPt.m_combinedRollingFriction = calculateCombinedRollingFriction(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
140 newPt.m_combinedSpinningFriction = calculateCombinedSpinningFriction(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
141
142 if ( (m_body0Wrap->getCollisionObject()->getCollisionFlags()& btCollisionObject::CF_HAS_CONTACT_STIFFNESS_DAMPING) ||
143 (m_body1Wrap->getCollisionObject()->getCollisionFlags()& btCollisionObject::CF_HAS_CONTACT_STIFFNESS_DAMPING))
144 {
145 newPt.m_combinedContactDamping1 = calculateCombinedContactDamping(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
146 newPt.m_combinedContactStiffness1 = calculateCombinedContactStiffness(m_body0Wrap->getCollisionObject(),m_body1Wrap->getCollisionObject());
147 newPt.m_contactPointFlags |= BT_CONTACT_FLAG_CONTACT_STIFFNESS_DAMPING;
148 }
149
150 if ( (m_body0Wrap->getCollisionObject()->getCollisionFlags()& btCollisionObject::CF_HAS_FRICTION_ANCHOR) ||
151 (m_body1Wrap->getCollisionObject()->getCollisionFlags()& btCollisionObject::CF_HAS_FRICTION_ANCHOR))
152 {
153 newPt.m_contactPointFlags |= BT_CONTACT_FLAG_FRICTION_ANCHOR;
154 }
155
156 btPlaneSpace1(newPt.m_normalWorldOnB,newPt.m_lateralFrictionDir1,newPt.m_lateralFrictionDir2);
157
158
159
160 //BP mod, store contact triangles.
161 if (isSwapped)
162 {
163 newPt.m_partId0 = m_partId1;
164 newPt.m_partId1 = m_partId0;
165 newPt.m_index0 = m_index1;
166 newPt.m_index1 = m_index0;
167 } else
168 {
169 newPt.m_partId0 = m_partId0;
170 newPt.m_partId1 = m_partId1;
171 newPt.m_index0 = m_index0;
172 newPt.m_index1 = m_index1;
173 }
174 //printf("depth=%f\n",depth);
176 if (insertIndex >= 0)
177 {
178 //const btManifoldPoint& oldPoint = m_manifoldPtr->getContactPoint(insertIndex);
179 m_manifoldPtr->replaceContactPoint(newPt,insertIndex);
180 } else
181 {
182 insertIndex = m_manifoldPtr->addManifoldPoint(newPt);
183 }
184
185 //User can override friction and/or restitution
186 if (gContactAddedCallback &&
187 //and if either of the two bodies requires custom material
188 ((m_body0Wrap->getCollisionObject()->getCollisionFlags() & btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK) ||
189 (m_body1Wrap->getCollisionObject()->getCollisionFlags() & btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK)))
190 {
191 //experimental feature info, for per-triangle material etc.
192 const btCollisionObjectWrapper* obj0Wrap = isSwapped? m_body1Wrap : m_body0Wrap;
193 const btCollisionObjectWrapper* obj1Wrap = isSwapped? m_body0Wrap : m_body1Wrap;
194 (*gContactAddedCallback)(m_manifoldPtr->getContactPoint(insertIndex),obj0Wrap,newPt.m_partId0,newPt.m_index0,obj1Wrap,newPt.m_partId1,newPt.m_index1);
195 }
196
197 if (gContactStartedCallback && isNewCollision)
198 {
199 gContactStartedCallback(m_manifoldPtr);
200 }
201 }
202
gContactStartedCallback
ContactStartedCallback gContactStartedCallback
Definition: btPersistentManifold.cpp:24
btManifoldPoint::m_contactPointFlags
int m_contactPointFlags
Definition: btManifoldPoint.h:116
btPersistentManifold::getContactBreakingThreshold
btScalar getContactBreakingThreshold() const
Definition: btPersistentManifold.cpp:242
btManifoldPoint::m_combinedContactStiffness1
btScalar m_combinedContactStiffness1
Definition: btManifoldPoint.h:127
btManifoldPoint::m_partId1
int m_partId1
Definition: btManifoldPoint.h:110
btManifoldPoint::m_lateralFrictionDir1
btVector3 m_lateralFrictionDir1
Definition: btManifoldPoint.h:140
btCollisionObject::getContactDamping
btScalar getContactDamping() const
Definition: btCollisionObject.h:361
btManifoldResult::calculateCombinedContactDamping
static btScalar calculateCombinedContactDamping(const btCollisionObject *body0, const btCollisionObject *body1)
Definition: btManifoldResult.cpp:71
btManifoldResult::m_manifoldPtr
btPersistentManifold * m_manifoldPtr
Definition: btManifoldResult.h:43
btManifoldResult.h
btManifoldPoint::m_combinedRestitution
btScalar m_combinedRestitution
Definition: btManifoldPoint.h:106
BT_CONTACT_FLAG_CONTACT_STIFFNESS_DAMPING
Definition: btManifoldPoint.h:43
btManifoldResult::calculateCombinedRollingFriction
static btScalar calculateCombinedRollingFriction(const btCollisionObject *body0, const btCollisionObject *body1)
Definition: btManifoldResult.cpp:27
btPersistentManifold::getNumContacts
int getNumContacts() const
Definition: btPersistentManifold.h:117
btCollisionObject::getContactStiffness
btScalar getContactStiffness() const
Definition: btCollisionObject.h:356
btPlaneSpace1
void btPlaneSpace1(const T &n, T &p, T &q)
Definition: btVector3.h:1283
btAssert
#define btAssert(x)
Definition: btScalar.h:131
btManifoldResult::calculateCombinedContactStiffness
static btScalar calculateCombinedContactStiffness(const btCollisionObject *body0, const btCollisionObject *body1)
Definition: btManifoldResult.cpp:76
btPersistentManifold.h
btManifoldPoint
ManifoldContactPoint collects and maintains persistent contactpoints.
Definition: btManifoldPoint.h:49
btManifoldResult::m_body1Wrap
const btCollisionObjectWrapper * m_body1Wrap
Definition: btManifoldResult.h:46
btPersistentManifold::getContactPoint
const btManifoldPoint & getContactPoint(int index) const
Definition: btPersistentManifold.h:125
btManifoldResult::addContactPoint
virtual void addContactPoint(const btVector3 &normalOnBInWorld, const btVector3 &pointInWorld, btScalar depth)
Definition: btManifoldResult.cpp:104
btManifoldPoint::m_combinedRollingFriction
btScalar m_combinedRollingFriction
Definition: btManifoldPoint.h:104
btCollisionObject::getWorldTransform
btTransform & getWorldTransform()
Definition: btCollisionObject.h:372
btManifoldPoint::m_normalWorldOnB
btVector3 m_normalWorldOnB
Definition: btManifoldPoint.h:100
btManifoldPoint::m_positionWorldOnB
btVector3 m_positionWorldOnB
Definition: btManifoldPoint.h:97
btPersistentManifold::getBody0
const btCollisionObject * getBody0() const
Definition: btPersistentManifold.h:102
btCollisionObjectWrapper::getCollisionObject
const btCollisionObject * getCollisionObject() const
Definition: btCollisionObjectWrapper.h:39
btCollisionObject::getRestitution
btScalar getRestitution() const
Definition: btCollisionObject.h:309
btCollisionObject
btCollisionObject can be used to manage collision detection objects.
Definition: btCollisionObject.h:49
btManifoldResult::btManifoldResult
btManifoldResult()
Definition: btManifoldResult.h:55
btManifoldPoint::m_positionWorldOnA
btVector3 m_positionWorldOnA
m_positionWorldOnA is redundant information, see getPositionWorldOnA(), but for clarity ...
Definition: btManifoldPoint.h:99
btCollisionObjectWrapper.h
btTransform::invXform
btVector3 invXform(const btVector3 &inVec) const
Definition: btTransform.h:223
btCollisionObject::getRollingFriction
btScalar getRollingFriction() const
Definition: btCollisionObject.h:328
btCollisionObject::getCollisionFlags
int getCollisionFlags() const
Definition: btCollisionObject.h:485
btManifoldResult::calculateCombinedFriction
static btScalar calculateCombinedFriction(const btCollisionObject *body0, const btCollisionObject *body1)
User can override this material combiner by implementing gContactAddedCallback and setting body0->m_c...
Definition: btManifoldResult.cpp:53
btVector3
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:83
ContactAddedCallback
bool(* ContactAddedCallback)(btManifoldPoint &cp, const btCollisionObjectWrapper *colObj0Wrap, int partId0, int index0, const btCollisionObjectWrapper *colObj1Wrap, int partId1, int index1)
Definition: btManifoldResult.h:32
btManifoldPoint::m_index1
int m_index1
Definition: btManifoldPoint.h:112
btManifoldPoint::m_combinedContactDamping1
btScalar m_combinedContactDamping1
Definition: btManifoldPoint.h:133
btCollisionObject::getSpinningFriction
btScalar getSpinningFriction() const
Definition: btCollisionObject.h:337
btCollisionObject::CF_HAS_CONTACT_STIFFNESS_DAMPING
Definition: btCollisionObject.h:140
BT_CONTACT_FLAG_FRICTION_ANCHOR
Definition: btManifoldPoint.h:44
btManifoldResult::calculateCombinedSpinningFriction
static btScalar calculateCombinedSpinningFriction(const btCollisionObject *body0, const btCollisionObject *body1)
Definition: btManifoldResult.cpp:40
btManifoldResult::m_index0
int m_index0
Definition: btManifoldResult.h:49
btCollisionObject.h
gContactAddedCallback
ContactAddedCallback gContactAddedCallback
This is to allow MaterialCombiner/Custom Friction/Restitution values.
Definition: btManifoldResult.cpp:23
btManifoldPoint::m_combinedFriction
btScalar m_combinedFriction
Definition: btManifoldPoint.h:103
btManifoldResult::m_body0Wrap
const btCollisionObjectWrapper * m_body0Wrap
Definition: btManifoldResult.h:45
btCollisionObject::CF_HAS_FRICTION_ANCHOR
Definition: btCollisionObject.h:142
btManifoldResult::m_index1
int m_index1
Definition: btManifoldResult.h:50
btManifoldResult::m_partId0
int m_partId0
Definition: btManifoldResult.h:47
btManifoldPoint::m_lateralFrictionDir2
btVector3 m_lateralFrictionDir2
Definition: btManifoldPoint.h:141
btPersistentManifold::replaceContactPoint
void replaceContactPoint(const btManifoldPoint &newPoint, int insertIndex)
Definition: btPersistentManifold.h:188
btManifoldResult::calculateCombinedRestitution
static btScalar calculateCombinedRestitution(const btCollisionObject *body0, const btCollisionObject *body1)
in the future we can let the user override the methods to combine restitution and friction ...
Definition: btManifoldResult.cpp:66
btCollisionObject::getFriction
btScalar getFriction() const
Definition: btCollisionObject.h:318
btCollisionObjectWrapper
Definition: btCollisionObjectWrapper.h:17
btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK
Definition: btCollisionObject.h:136
btPersistentManifold::addManifoldPoint
int addManifoldPoint(const btManifoldPoint &newPoint, bool isPredictive=false)
Definition: btPersistentManifold.cpp:210
btManifoldPoint::m_partId0
int m_partId0
Definition: btManifoldPoint.h:109
btManifoldResult::m_partId1
int m_partId1
Definition: btManifoldResult.h:48
btScalar
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:292
btManifoldPoint::m_combinedSpinningFriction
btScalar m_combinedSpinningFriction
Definition: btManifoldPoint.h:105
btManifoldPoint::m_index0
int m_index0
Definition: btManifoldPoint.h:111
btPersistentManifold::getCacheEntry
int getCacheEntry(const btManifoldPoint &newPoint) const
Definition: btPersistentManifold.cpp:190