Bart/bullet3
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fixes in btContinuousConvexCollision, should fix Issue 347

Browse Source 
Continuous sweeps do not detect hits unless body0 and body1 penetrate more than allowedCcdPenetration.
This is to allow sliding objects (characters) where otherwise any contact would result in TOI = 0.
If objects penetrate deeper than allowedCcdPenetration at the start of the sweep, a TOI=0 is reported, unless the motion will separate the objects.

Secondly, a reportFailure method is added to CastResults, to handle failures gracefully (in case max iterations of conservative advancement is reached etc)
This commit is contained in:
erwin.coumans
2011-03-31 21:14:35 +00:00
parent 88b19eb023
commit 0bef2e7363
2 changed files with 14 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files

58
src/BulletCollision/NarrowPhaseCollision/btContinuousConvexCollision.cpp
View File

@@ -64,7 +64,6 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
return false;
btScalar radius = btScalar(0.001);
btScalar lambda = btScalar(0.);
btVector3 v(1,0,0);
@@ -82,14 +81,12 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
int numIter = 0;
//first solution, using GJK
btTransform identityTrans;
identityTrans.setIdentity();
btSphereShape raySphere(btScalar(0.0));
raySphere.setMargin(btScalar(0.));
// result.drawCoordSystem(sphereTr);
btPointCollector pointCollector1;
@@ -99,8 +96,6 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
btGjkPairDetector gjk(m_convexA,m_convexB,m_convexA->getShapeType(),m_convexB->getShapeType(),m_convexA->getMargin(),m_convexB->getMargin(),m_simplexSolver,m_penetrationDepthSolver);
btGjkPairDetector::ClosestPointInput input;
//we don't use margins during CCD
// gjk.setIgnoreMargin(true);
input.m_transformA = fromA;
input.m_transformB = fromB;
@@ -113,31 +108,23 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
if (hasResult)
{
btScalar dist;
dist = pointCollector1.m_distance;
dist = pointCollector1.m_distance + result.m_allowedPenetration;
n = pointCollector1.m_normalOnBInWorld;
btScalar projectedLinearVelocity = relLinVel.dot(n);
if ((projectedLinearVelocity+ maxAngularProjectedVelocity)<=SIMD_EPSILON)
return false;
//not close enough
while (dist > radius)
while (dist > SIMD_EPSILON)
{
if (result.m_debugDrawer)
{
result.m_debugDrawer->drawSphere(c,0.2f,btVector3(1,1,1));
}
numIter++;
if (numIter > maxIter)
{
return false; //todo: report a failure
}
btScalar dLambda = btScalar(0.);
projectedLinearVelocity = relLinVel.dot(n);
//calculate safe moving fraction from distance / (linear+rotational velocity)
//btScalar clippedDist = GEN_min(angularConservativeRadius,dist);
//btScalar clippedDist = dist;
//don't report time of impact for motion away from the contact normal (or causes minor penetration)
if ((projectedLinearVelocity+ maxAngularProjectedVelocity)<=SIMD_EPSILON)
@@ -189,30 +176,23 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
gjk.getClosestPoints(input,pointCollector,0);
if (pointCollector.m_hasResult)
{
if (pointCollector.m_distance < btScalar(0.))
{
//degenerate ?!
result.m_fraction = lastLambda;
n = pointCollector.m_normalOnBInWorld;
result.m_normal=n;//.setValue(1,1,1);// = n;
result.m_hitPoint = pointCollector.m_pointInWorld;
return true;
}
dist = pointCollector.m_distance+result.m_allowedPenetration;
c = pointCollector.m_pointInWorld;
n = pointCollector.m_normalOnBInWorld;
dist = pointCollector.m_distance;
} else
{
//??
result.reportFailure(-1, numIter);
return false;
}
numIter++;
if (numIter > maxIter)
{
result.reportFailure(-2, numIter);
return false;
}
}
if ((projectedLinearVelocity+ maxAngularProjectedVelocity)<=result.m_allowedPenetration)//SIMD_EPSILON)
return false;
result.m_fraction = lambda;
result.m_normal = n;
result.m_hitPoint = c;
@@ -221,16 +201,4 @@ bool btContinuousConvexCollision::calcTimeOfImpact(
return false;
/*
//todo:
//if movement away from normal, discard result
btVector3 move = transBLocalTo.getOrigin() - transBLocalFrom.getOrigin();
if (result.m_fraction < btScalar(1.))
{
if (move.dot(result.m_normal) <= btScalar(0.))
{
}
}
*/
}