177 lines
4.6 KiB
C++
177 lines
4.6 KiB
C++
/*
|
|
Bullet Continuous Collision Detection and Physics Library
|
|
Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
|
|
|
|
This software is provided 'as-is', without any express or implied warranty.
|
|
In no event will the authors be held liable for any damages arising from the use of this software.
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it freely,
|
|
subject to the following restrictions:
|
|
|
|
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.
|
|
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
*/
|
|
|
|
|
|
|
|
#include "btGjkConvexCast.h"
|
|
#include "BulletCollision/CollisionShapes/btSphereShape.h"
|
|
#include "btGjkPairDetector.h"
|
|
#include "btPointCollector.h"
|
|
#include "LinearMath/btTransformUtil.h"
|
|
|
|
#ifdef BT_USE_DOUBLE_PRECISION
|
|
#define MAX_ITERATIONS 64
|
|
#else
|
|
#define MAX_ITERATIONS 32
|
|
#endif
|
|
|
|
btGjkConvexCast::btGjkConvexCast(const btConvexShape* convexA,const btConvexShape* convexB,btSimplexSolverInterface* simplexSolver)
|
|
:m_simplexSolver(simplexSolver),
|
|
m_convexA(convexA),
|
|
m_convexB(convexB)
|
|
{
|
|
}
|
|
|
|
bool btGjkConvexCast::calcTimeOfImpact(
|
|
const btTransform& fromA,
|
|
const btTransform& toA,
|
|
const btTransform& fromB,
|
|
const btTransform& toB,
|
|
CastResult& result)
|
|
{
|
|
|
|
|
|
m_simplexSolver->reset();
|
|
|
|
/// compute linear velocity for this interval, to interpolate
|
|
//assume no rotation/angular velocity, assert here?
|
|
btVector3 linVelA,linVelB;
|
|
linVelA = toA.getOrigin()-fromA.getOrigin();
|
|
linVelB = toB.getOrigin()-fromB.getOrigin();
|
|
|
|
btScalar radius = btScalar(0.001);
|
|
btScalar lambda = btScalar(0.);
|
|
btVector3 v(1,0,0);
|
|
|
|
int maxIter = MAX_ITERATIONS;
|
|
|
|
btVector3 n;
|
|
n.setValue(btScalar(0.),btScalar(0.),btScalar(0.));
|
|
bool hasResult = false;
|
|
btVector3 c;
|
|
btVector3 r = (linVelA-linVelB);
|
|
|
|
btScalar lastLambda = lambda;
|
|
//btScalar epsilon = btScalar(0.001);
|
|
|
|
int numIter = 0;
|
|
//first solution, using GJK
|
|
|
|
|
|
btTransform identityTrans;
|
|
identityTrans.setIdentity();
|
|
|
|
|
|
// result.drawCoordSystem(sphereTr);
|
|
|
|
btPointCollector pointCollector;
|
|
|
|
|
|
btGjkPairDetector gjk(m_convexA,m_convexB,m_simplexSolver,0);//m_penetrationDepthSolver);
|
|
btGjkPairDetector::ClosestPointInput input;
|
|
|
|
//we don't use margins during CCD
|
|
// gjk.setIgnoreMargin(true);
|
|
|
|
input.m_transformA = fromA;
|
|
input.m_transformB = fromB;
|
|
gjk.getClosestPoints(input,pointCollector,0);
|
|
|
|
hasResult = pointCollector.m_hasResult;
|
|
c = pointCollector.m_pointInWorld;
|
|
|
|
if (hasResult)
|
|
{
|
|
btScalar dist;
|
|
dist = pointCollector.m_distance;
|
|
n = pointCollector.m_normalOnBInWorld;
|
|
|
|
|
|
|
|
//not close enough
|
|
while (dist > radius)
|
|
{
|
|
numIter++;
|
|
if (numIter > maxIter)
|
|
{
|
|
return false; //todo: report a failure
|
|
}
|
|
btScalar dLambda = btScalar(0.);
|
|
|
|
btScalar projectedLinearVelocity = r.dot(n);
|
|
|
|
dLambda = dist / (projectedLinearVelocity);
|
|
|
|
lambda = lambda - dLambda;
|
|
|
|
if (lambda > btScalar(1.))
|
|
return false;
|
|
|
|
if (lambda < btScalar(0.))
|
|
return false;
|
|
|
|
//todo: next check with relative epsilon
|
|
if (lambda <= lastLambda)
|
|
{
|
|
return false;
|
|
//n.setValue(0,0,0);
|
|
break;
|
|
}
|
|
lastLambda = lambda;
|
|
|
|
//interpolate to next lambda
|
|
result.DebugDraw( lambda );
|
|
input.m_transformA.getOrigin().setInterpolate3(fromA.getOrigin(),toA.getOrigin(),lambda);
|
|
input.m_transformB.getOrigin().setInterpolate3(fromB.getOrigin(),toB.getOrigin(),lambda);
|
|
|
|
gjk.getClosestPoints(input,pointCollector,0);
|
|
if (pointCollector.m_hasResult)
|
|
{
|
|
if (pointCollector.m_distance < btScalar(0.))
|
|
{
|
|
result.m_fraction = lastLambda;
|
|
n = pointCollector.m_normalOnBInWorld;
|
|
result.m_normal=n;
|
|
result.m_hitPoint = pointCollector.m_pointInWorld;
|
|
return true;
|
|
}
|
|
c = pointCollector.m_pointInWorld;
|
|
n = pointCollector.m_normalOnBInWorld;
|
|
dist = pointCollector.m_distance;
|
|
} else
|
|
{
|
|
//??
|
|
return false;
|
|
}
|
|
|
|
}
|
|
|
|
//is n normalized?
|
|
//don't report time of impact for motion away from the contact normal (or causes minor penetration)
|
|
if (n.dot(r)>=-result.m_allowedPenetration)
|
|
return false;
|
|
|
|
result.m_fraction = lambda;
|
|
result.m_normal = n;
|
|
result.m_hitPoint = c;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
|
|
|
|
}
|
|
|