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btContinuousConvexCollision.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 "btContinuousConvexCollision.h"
18 #include "BulletCollision/CollisionShapes/btConvexShape.h"
19 #include "BulletCollision/NarrowPhaseCollision/btSimplexSolverInterface.h"
20 #include "LinearMath/btTransformUtil.h"
21 #include "BulletCollision/CollisionShapes/btSphereShape.h"
22
23 #include "btGjkPairDetector.h"
24 #include "btPointCollector.h"
25 #include "BulletCollision/CollisionShapes/btStaticPlaneShape.h"
26
27
28
29 btContinuousConvexCollision::btContinuousConvexCollision ( const btConvexShape* convexA,const btConvexShape* convexB,btSimplexSolverInterface* simplexSolver, btConvexPenetrationDepthSolver* penetrationDepthSolver)
30 :m_simplexSolver(simplexSolver),
31 m_penetrationDepthSolver(penetrationDepthSolver),
32 m_convexA(convexA),m_convexB1(convexB),m_planeShape(0)
33 {
34 }
35
36
37 btContinuousConvexCollision::btContinuousConvexCollision( const btConvexShape* convexA,const btStaticPlaneShape* plane)
38 :m_simplexSolver(0),
39 m_penetrationDepthSolver(0),
40 m_convexA(convexA),m_convexB1(0),m_planeShape(plane)
41 {
42 }
43
44
47 #define MAX_ITERATIONS 64
48
49 void btContinuousConvexCollision::computeClosestPoints( const btTransform& transA, const btTransform& transB,btPointCollector& pointCollector)
50 {
51 if (m_convexB1)
52 {
53 m_simplexSolver->reset();
54 btGjkPairDetector gjk(m_convexA,m_convexB1,m_convexA->getShapeType(),m_convexB1->getShapeType(),m_convexA->getMargin(),m_convexB1->getMargin(),m_simplexSolver,m_penetrationDepthSolver);
55 btGjkPairDetector::ClosestPointInput input;
56 input.m_transformA = transA;
57 input.m_transformB = transB;
58 gjk.getClosestPoints(input,pointCollector,0);
59 } else
60 {
61 //convex versus plane
62 const btConvexShape* convexShape = m_convexA;
63 const btStaticPlaneShape* planeShape = m_planeShape;
64
65 const btVector3& planeNormal = planeShape->getPlaneNormal();
66 const btScalar& planeConstant = planeShape->getPlaneConstant();
67
68 btTransform convexWorldTransform = transA;
69 btTransform convexInPlaneTrans;
70 convexInPlaneTrans= transB.inverse() * convexWorldTransform;
71 btTransform planeInConvex;
72 planeInConvex= convexWorldTransform.inverse() * transB;
73
74 btVector3 vtx = convexShape->localGetSupportingVertex(planeInConvex.getBasis()*-planeNormal);
75
76 btVector3 vtxInPlane = convexInPlaneTrans(vtx);
77 btScalar distance = (planeNormal.dot(vtxInPlane) - planeConstant);
78
79 btVector3 vtxInPlaneProjected = vtxInPlane - distance*planeNormal;
80 btVector3 vtxInPlaneWorld = transB * vtxInPlaneProjected;
81 btVector3 normalOnSurfaceB = transB.getBasis() * planeNormal;
82
83 pointCollector.addContactPoint(
84 normalOnSurfaceB,
85 vtxInPlaneWorld,
86 distance);
87 }
88 }
89
90 bool btContinuousConvexCollision::calcTimeOfImpact(
91 const btTransform& fromA,
92 const btTransform& toA,
93 const btTransform& fromB,
94 const btTransform& toB,
95 CastResult& result)
96 {
97
98
100 btVector3 linVelA,angVelA,linVelB,angVelB;
101 btTransformUtil::calculateVelocity(fromA,toA,btScalar(1.),linVelA,angVelA);
102 btTransformUtil::calculateVelocity(fromB,toB,btScalar(1.),linVelB,angVelB);
103
104
105 btScalar boundingRadiusA = m_convexA->getAngularMotionDisc();
106 btScalar boundingRadiusB = m_convexB1?m_convexB1->getAngularMotionDisc():0.f;
107
108 btScalar maxAngularProjectedVelocity = angVelA.length() * boundingRadiusA + angVelB.length() * boundingRadiusB;
109 btVector3 relLinVel = (linVelB-linVelA);
110
111 btScalar relLinVelocLength = (linVelB-linVelA).length();
112
113 if ((relLinVelocLength+maxAngularProjectedVelocity) == 0.f)
114 return false;
115
116
117
118 btScalar lambda = btScalar(0.);
119 btVector3 v(1,0,0);
120
121 int maxIter = MAX_ITERATIONS;
122
123 btVector3 n;
124 n.setValue(btScalar(0.),btScalar(0.),btScalar(0.));
125 bool hasResult = false;
126 btVector3 c;
127
128 btScalar lastLambda = lambda;
129 //btScalar epsilon = btScalar(0.001);
130
131 int numIter = 0;
132 //first solution, using GJK
133
134
135 btScalar radius = 0.001f;
136 // result.drawCoordSystem(sphereTr);
137
138 btPointCollector pointCollector1;
139
140 {
141
142 computeClosestPoints(fromA,fromB,pointCollector1);
143
144 hasResult = pointCollector1.m_hasResult;
145 c = pointCollector1.m_pointInWorld;
146 }
147
148 if (hasResult)
149 {
150 btScalar dist;
151 dist = pointCollector1.m_distance + result.m_allowedPenetration;
152 n = pointCollector1.m_normalOnBInWorld;
153 btScalar projectedLinearVelocity = relLinVel.dot(n);
154 if ((projectedLinearVelocity+ maxAngularProjectedVelocity)<=SIMD_EPSILON)
155 return false;
156
157 //not close enough
158 while (dist > radius)
159 {
160 if (result.m_debugDrawer)
161 {
162 result.m_debugDrawer->drawSphere(c,0.2f,btVector3(1,1,1));
163 }
164 btScalar dLambda = btScalar(0.);
165
166 projectedLinearVelocity = relLinVel.dot(n);
167
168
169 //don't report time of impact for motion away from the contact normal (or causes minor penetration)
170 if ((projectedLinearVelocity+ maxAngularProjectedVelocity)<=SIMD_EPSILON)
171 return false;
172
173 dLambda = dist / (projectedLinearVelocity+ maxAngularProjectedVelocity);
174
175
176
177 lambda = lambda + dLambda;
178
179 if (lambda > btScalar(1.))
180 return false;
181
182 if (lambda < btScalar(0.))
183 return false;
184
185
186 //todo: next check with relative epsilon
187 if (lambda <= lastLambda)
188 {
189 return false;
190 //n.setValue(0,0,0);
191 break;
192 }
193 lastLambda = lambda;
194
195
196
197 //interpolate to next lambda
198 btTransform interpolatedTransA,interpolatedTransB,relativeTrans;
199
200 btTransformUtil::integrateTransform(fromA,linVelA,angVelA,lambda,interpolatedTransA);
201 btTransformUtil::integrateTransform(fromB,linVelB,angVelB,lambda,interpolatedTransB);
202 relativeTrans = interpolatedTransB.inverseTimes(interpolatedTransA);
203
204 if (result.m_debugDrawer)
205 {
206 result.m_debugDrawer->drawSphere(interpolatedTransA.getOrigin(),0.2f,btVector3(1,0,0));
207 }
208
209 result.DebugDraw( lambda );
210
211 btPointCollector pointCollector;
212 computeClosestPoints(interpolatedTransA,interpolatedTransB,pointCollector);
213
214 if (pointCollector.m_hasResult)
215 {
216 dist = pointCollector.m_distance+result.m_allowedPenetration;
217 c = pointCollector.m_pointInWorld;
218 n = pointCollector.m_normalOnBInWorld;
219 } else
220 {
221 result.reportFailure(-1, numIter);
222 return false;
223 }
224
225 numIter++;
226 if (numIter > maxIter)
227 {
228 result.reportFailure(-2, numIter);
229 return false;
230 }
231 }
232
233 result.m_fraction = lambda;
234 result.m_normal = n;
235 result.m_hitPoint = c;
236 return true;
237 }
238
239 return false;
240
241 }
242
SIMD_EPSILON
#define SIMD_EPSILON
Definition: btScalar.h:494
btContinuousConvexCollision::computeClosestPoints
void computeClosestPoints(const btTransform &transA, const btTransform &transB, struct btPointCollector &pointCollector)
Definition: btContinuousConvexCollision.cpp:49
length
btScalar length(const btQuaternion &q)
Return the length of a quaternion.
Definition: btQuaternion.h:853
btTransformUtil.h
btCollisionShape::getShapeType
int getShapeType() const
Definition: btCollisionShape.h:112
btConvexShape::localGetSupportingVertex
virtual btVector3 localGetSupportingVertex(const btVector3 &vec) const =0
btConvexCast::CastResult::m_fraction
btScalar m_fraction
Definition: btConvexCast.h:57
btPointCollector.h
btVector3::setValue
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
btConvexPenetrationDepthSolver
ConvexPenetrationDepthSolver provides an interface for penetration depth calculation.
Definition: btConvexPenetrationDepthSolver.h:26
btStaticPlaneShape::getPlaneNormal
const btVector3 & getPlaneNormal() const
Definition: btStaticPlaneShape.h:50
btStaticPlaneShape.h
btPointCollector::m_distance
btScalar m_distance
Definition: btPointCollector.h:29
btDiscreteCollisionDetectorInterface::ClosestPointInput::m_transformA
btTransform m_transformA
Definition: btDiscreteCollisionDetectorInterface.h:49
btVector3::dot
btScalar dot(const btVector3 &v) const
Return the dot product.
Definition: btVector3.h:235
btConvexShape.h
btGjkPairDetector.h
btTransform::inverseTimes
btTransform inverseTimes(const btTransform &t) const
Return the inverse of this transform times the other transform.
Definition: btTransform.h:230
MAX_ITERATIONS
#define MAX_ITERATIONS
This maximum should not be necessary.
Definition: btContinuousConvexCollision.cpp:47
btConvexCast::CastResult::m_normal
btVector3 m_normal
Definition: btConvexCast.h:55
btConvexShape
The btConvexShape is an abstract shape interface, implemented by all convex shapes such as btBoxShape...
Definition: btConvexShape.h:31
btConvexCast::CastResult::m_allowedPenetration
btScalar m_allowedPenetration
Definition: btConvexCast.h:59
btPointCollector
Definition: btPointCollector.h:23
btConvexCast::CastResult::DebugDraw
virtual void DebugDraw(btScalar fraction)
Definition: btConvexCast.h:40
btConvexCast::CastResult::m_debugDrawer
btIDebugDraw * m_debugDrawer
Definition: btConvexCast.h:58
btConvexCast::CastResult
RayResult stores the closest result alternatively, add a callback method to decide about closest/all ...
Definition: btConvexCast.h:36
btTransform::getOrigin
btVector3 & getOrigin()
Return the origin vector translation.
Definition: btTransform.h:117
btSimplexSolverInterface
#define btSimplexSolverInterface
Definition: btSimplexSolverInterface.h:26
btContinuousConvexCollision::m_simplexSolver
btSimplexSolverInterface * m_simplexSolver
Definition: btContinuousConvexCollision.h:32
btPointCollector::m_pointInWorld
btVector3 m_pointInWorld
Definition: btPointCollector.h:28
btTransform::getBasis
btMatrix3x3 & getBasis()
Return the basis matrix for the rotation.
Definition: btTransform.h:112
btVector3::length
btScalar length() const
Return the length of the vector.
Definition: btVector3.h:263
btTransform::inverse
btTransform inverse() const
Return the inverse of this transform.
Definition: btTransform.h:188
btContinuousConvexCollision::m_convexA
const btConvexShape * m_convexA
Definition: btContinuousConvexCollision.h:34
btContinuousConvexCollision.h
btConvexShape::getMargin
virtual btScalar getMargin() const =0
btContinuousConvexCollision::m_penetrationDepthSolver
btConvexPenetrationDepthSolver * m_penetrationDepthSolver
Definition: btContinuousConvexCollision.h:33
btCollisionShape::getAngularMotionDisc
virtual btScalar getAngularMotionDisc() const
getAngularMotionDisc returns the maximus radius needed for Conservative Advancement to handle time-of...
Definition: btCollisionShape.cpp:50
btVector3
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:83
btTransformUtil::integrateTransform
static void integrateTransform(const btTransform &curTrans, const btVector3 &linvel, const btVector3 &angvel, btScalar timeStep, btTransform &predictedTransform)
Definition: btTransformUtil.h:43
btTransform
The btTransform class supports rigid transforms with only translation and rotation and no scaling/she...
Definition: btTransform.h:34
btConvexCast::CastResult::m_hitPoint
btVector3 m_hitPoint
Definition: btConvexCast.h:56
btPointCollector::addContactPoint
virtual void addContactPoint(const btVector3 &normalOnBInWorld, const btVector3 &pointInWorld, btScalar depth)
Definition: btPointCollector.h:50
btContinuousConvexCollision::calcTimeOfImpact
virtual bool calcTimeOfImpact(const btTransform &fromA, const btTransform &toA, const btTransform &fromB, const btTransform &toB, CastResult &result)
cast a convex against another convex object
Definition: btContinuousConvexCollision.cpp:90
btGjkPairDetector
btGjkPairDetector uses GJK to implement the btDiscreteCollisionDetectorInterface
Definition: btGjkPairDetector.h:30
btContinuousConvexCollision::m_convexB1
const btConvexShape * m_convexB1
Definition: btContinuousConvexCollision.h:36
btPointCollector::m_hasResult
bool m_hasResult
Definition: btPointCollector.h:31
btContinuousConvexCollision::btContinuousConvexCollision
btContinuousConvexCollision(const btConvexShape *shapeA, const btConvexShape *shapeB, btSimplexSolverInterface *simplexSolver, btConvexPenetrationDepthSolver *penetrationDepthSolver)
Definition: btContinuousConvexCollision.cpp:29
btStaticPlaneShape
The btStaticPlaneShape simulates an infinite non-moving (static) collision plane. ...
Definition: btStaticPlaneShape.h:23
btDiscreteCollisionDetectorInterface::ClosestPointInput
Definition: btDiscreteCollisionDetectorInterface.h:42
btSimplexSolverInterface.h
btSphereShape.h
btTransformUtil::calculateVelocity
static void calculateVelocity(const btTransform &transform0, const btTransform &transform1, btScalar timeStep, btVector3 &linVel, btVector3 &angVel)
Definition: btTransformUtil.h:112
btIDebugDraw::drawSphere
virtual void drawSphere(btScalar radius, const btTransform &transform, const btVector3 &color)
Definition: btIDebugDraw.h:93
btConvexCast::CastResult::reportFailure
virtual void reportFailure(int errNo, int numIterations)
Definition: btConvexCast.h:42
btPointCollector::m_normalOnBInWorld
btVector3 m_normalOnBInWorld
Definition: btPointCollector.h:27
btScalar
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:278
btStaticPlaneShape::getPlaneConstant
const btScalar & getPlaneConstant() const
Definition: btStaticPlaneShape.h:55
btContinuousConvexCollision::m_planeShape
const btStaticPlaneShape * m_planeShape
Definition: btContinuousConvexCollision.h:37