internal override double calculateTimeOfImpact( btCollisionObject col0, btCollisionObject col1, btDispatcherInfo dispatchInfo, btManifoldResult resultOut )
{
//(void)resultOut;
//(void)dispatchInfo;
///Rather then checking ALL pairs, only calculate TOI when motion exceeds threshold
///Linear motion for one of objects needs to exceed m_ccdSquareMotionThreshold
///col0.m_worldTransform,
double resultFraction = btScalar.BT_ONE;
btVector3 tmp;
col0.m_interpolationWorldTransform.m_origin.Sub( ref col0.m_worldTransform.m_origin, out tmp );
double squareMot0 = ( tmp ).length2();
col1.m_interpolationWorldTransform.m_origin.Sub( ref col1.m_worldTransform.m_origin, out tmp );
double squareMot1 = ( tmp ).length2();
if( squareMot0 < col0.getCcdSquareMotionThreshold() &&
squareMot1 < col1.getCcdSquareMotionThreshold() )
return resultFraction;
if( disableCcd )
return btScalar.BT_ONE;
//An adhoc way of testing the Continuous Collision Detection algorithms
//One object is approximated as a sphere, to simplify things
//Starting in penetration should report no time of impact
//For proper CCD, better accuracy and handling of 'allowed' penetration should be added
//also the mainloop of the physics should have a kind of toi queue (something like Brian Mirtich's application of Timewarp for Rigidbodies)
/// Convex0 against sphere for Convex1
{
btConvexShape convex0 = (btConvexShape)col0.getCollisionShape();
using( btSphereShape sphere1 = BulletGlobals.SphereShapePool.Get() )
{
sphere1.Initialize( col1.getCcdSweptSphereRadius() ); //todo: allow non-zero sphere sizes, for better approximation
btConvexCast.CastResult result = BulletGlobals.CastResultPool.Get();
btVoronoiSimplexSolver voronoiSimplex = BulletGlobals.VoronoiSimplexSolverPool.Get();
//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
///Simplification, one object is simplified as a sphere
btGjkConvexCast ccd1 = BulletGlobals.GjkConvexCastPool.Get();
ccd1.Initialize( convex0, sphere1, voronoiSimplex );
//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
if( ccd1.calcTimeOfImpact( ref col0.m_worldTransform, ref col0.m_interpolationWorldTransform,
ref col1.m_worldTransform, ref col1.m_interpolationWorldTransform, result ) )
{
//store result.m_fraction in both bodies
if( col0.getHitFraction() > result.m_fraction )
col0.setHitFraction( result.m_fraction );
if( col1.getHitFraction() > result.m_fraction )
col1.setHitFraction( result.m_fraction );
if( resultFraction > result.m_fraction )
resultFraction = result.m_fraction;
}
BulletGlobals.GjkConvexCastPool.Free( ccd1 );
}
}
/// Sphere (for convex0) against Convex1
{
btConvexShape convex1 = (btConvexShape)( col1.getCollisionShape() );
using( btSphereShape sphere0 = BulletGlobals.SphereShapePool.Get() )
{
sphere0.Initialize( col0.getCcdSweptSphereRadius() ); //todo: allow non-zero sphere sizes, for better approximation
btConvexCast.CastResult result = BulletGlobals.CastResultPool.Get();
btVoronoiSimplexSolver voronoiSimplex = BulletGlobals.VoronoiSimplexSolverPool.Get();
//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
///Simplification, one object is simplified as a sphere
btGjkConvexCast ccd1 = BulletGlobals.GjkConvexCastPool.Get();
ccd1.Initialize( sphere0, convex1, voronoiSimplex );
//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
if( ccd1.calcTimeOfImpact( ref col0.m_worldTransform, ref col0.m_interpolationWorldTransform,
ref col1.m_worldTransform, ref col1.m_interpolationWorldTransform, result ) )
{
//store result.m_fraction in both bodies
if( col0.getHitFraction() > result.m_fraction )
col0.setHitFraction( result.m_fraction );
if( col1.getHitFraction() > result.m_fraction )
col1.setHitFraction( result.m_fraction );
if( resultFraction > result.m_fraction )
resultFraction = result.m_fraction;
}
BulletGlobals.GjkConvexCastPool.Free( ccd1 );
}
}
return resultFraction;
}