Planet
navi homePPSaboutscreenshotsdownloaddevelopmentforum

source: code/archive/environment2/src/external/bullet/BulletCollision/NarrowPhaseCollision/btGjkConvexCast.cpp @ 9365

Last change on this file since 9365 was 5781, checked in by rgrieder, 15 years ago

Reverted trunk again. We might want to find a way to delete these revisions again (x3n's changes are still available as diff in the commit mails).

  • Property svn:eol-style set to native
File size: 4.5 KB
Line 
1/*
2Bullet Continuous Collision Detection and Physics Library
3Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
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
16
17
18#include "btGjkConvexCast.h"
19#include "BulletCollision/CollisionShapes/btSphereShape.h"
20#include "btGjkPairDetector.h"
21#include "btPointCollector.h"
22#include "LinearMath/btTransformUtil.h"
23
24#ifdef BT_USE_DOUBLE_PRECISION
25#define MAX_ITERATIONS 64
26#else
27#define MAX_ITERATIONS 32
28#endif
29
30btGjkConvexCast::btGjkConvexCast(const btConvexShape* convexA,const btConvexShape* convexB,btSimplexSolverInterface* simplexSolver)
31:m_simplexSolver(simplexSolver),
32m_convexA(convexA),
33m_convexB(convexB)
34{
35}
36
37bool    btGjkConvexCast::calcTimeOfImpact(
38                                        const btTransform& fromA,
39                                        const btTransform& toA,
40                                        const btTransform& fromB,
41                                        const btTransform& toB,
42                                        CastResult& result)
43{
44
45
46        m_simplexSolver->reset();
47
48        /// compute linear velocity for this interval, to interpolate
49        //assume no rotation/angular velocity, assert here?
50        btVector3 linVelA,linVelB;
51        linVelA = toA.getOrigin()-fromA.getOrigin();
52        linVelB = toB.getOrigin()-fromB.getOrigin();
53
54        btScalar radius = btScalar(0.001);
55        btScalar lambda = btScalar(0.);
56        btVector3 v(1,0,0);
57
58        int maxIter = MAX_ITERATIONS;
59
60        btVector3 n;
61        n.setValue(btScalar(0.),btScalar(0.),btScalar(0.));
62        bool hasResult = false;
63        btVector3 c;
64        btVector3 r = (linVelA-linVelB);
65
66        btScalar lastLambda = lambda;
67        //btScalar epsilon = btScalar(0.001);
68
69        int numIter = 0;
70        //first solution, using GJK
71
72
73        btTransform identityTrans;
74        identityTrans.setIdentity();
75
76
77//      result.drawCoordSystem(sphereTr);
78
79        btPointCollector        pointCollector;
80
81               
82        btGjkPairDetector gjk(m_convexA,m_convexB,m_simplexSolver,0);//m_penetrationDepthSolver);               
83        btGjkPairDetector::ClosestPointInput input;
84
85        //we don't use margins during CCD
86        //      gjk.setIgnoreMargin(true);
87
88        input.m_transformA = fromA;
89        input.m_transformB = fromB;
90        gjk.getClosestPoints(input,pointCollector,0);
91
92        hasResult = pointCollector.m_hasResult;
93        c = pointCollector.m_pointInWorld;
94
95        if (hasResult)
96        {
97                btScalar dist;
98                dist = pointCollector.m_distance;
99                n = pointCollector.m_normalOnBInWorld;
100
101       
102
103                //not close enough
104                while (dist > radius)
105                {
106                        numIter++;
107                        if (numIter > maxIter)
108                        {
109                                return false; //todo: report a failure
110                        }
111                        btScalar dLambda = btScalar(0.);
112
113                        btScalar projectedLinearVelocity = r.dot(n);
114                       
115                        dLambda = dist / (projectedLinearVelocity);
116
117                        lambda = lambda - dLambda;
118
119                        if (lambda > btScalar(1.))
120                                return false;
121
122                        if (lambda < btScalar(0.))
123                                return false;
124
125                        //todo: next check with relative epsilon
126                        if (lambda <= lastLambda)
127                        {
128                                return false;
129                                //n.setValue(0,0,0);
130                                break;
131                        }
132                        lastLambda = lambda;
133
134                        //interpolate to next lambda
135                        result.DebugDraw( lambda );
136                        input.m_transformA.getOrigin().setInterpolate3(fromA.getOrigin(),toA.getOrigin(),lambda);
137                        input.m_transformB.getOrigin().setInterpolate3(fromB.getOrigin(),toB.getOrigin(),lambda);
138                       
139                        gjk.getClosestPoints(input,pointCollector,0);
140                        if (pointCollector.m_hasResult)
141                        {
142                                if (pointCollector.m_distance < btScalar(0.))
143                                {
144                                        result.m_fraction = lastLambda;
145                                        n = pointCollector.m_normalOnBInWorld;
146                                        result.m_normal=n;
147                                        result.m_hitPoint = pointCollector.m_pointInWorld;
148                                        return true;
149                                }
150                                c = pointCollector.m_pointInWorld;             
151                                n = pointCollector.m_normalOnBInWorld;
152                                dist = pointCollector.m_distance;
153                        } else
154                        {
155                                //??
156                                return false;
157                        }
158
159                }
160
161                //is n normalized?
162                //don't report time of impact for motion away from the contact normal (or causes minor penetration)
163                if (n.dot(r)>=-result.m_allowedPenetration)
164                        return false;
165
166                result.m_fraction = lambda;
167                result.m_normal = n;
168                result.m_hitPoint = c;
169                return true;
170        }
171
172        return false;
173
174
175}
176
Note: See TracBrowser for help on using the repository browser.