public static void Contacts(int particleIndex,
int colliderIndex,
float4 position,
quaternion orientation,
float4 radii,
ref NativeArray <BurstDFNode> dfNodes,
DistanceFieldHeader header,
BurstAffineTransform colliderToSolver,
BurstColliderShape shape,
NativeQueue <BurstContact> .ParallelWriter contacts)
{
float4 pos = colliderToSolver.InverseTransformPoint(position);
BurstContact c = new BurstContact
{
entityA = particleIndex,
entityB = colliderIndex,
};
float4 sample = DFTraverse(pos, 0, ref header, ref dfNodes);
c.normal = new float4(math.normalize(sample.xyz), 0);
c.point = pos - c.normal * sample[3];
c.normal = colliderToSolver.TransformDirection(c.normal);
c.point = colliderToSolver.TransformPoint(c.point);
c.distance = sample[3] * math.cmax(colliderToSolver.scale.xyz) - (shape.contactOffset + BurstMath.EllipsoidRadius(c.normal, orientation, radii.xyz));
contacts.Enqueue(c);
}
private static float4 DFTraverse(float4 particlePosition,
int nodeIndex,
ref DistanceFieldHeader header,
ref NativeArray <BurstDFNode> dfNodes)
{
var node = dfNodes[header.firstNode + nodeIndex];
// if the child node exists, recurse down the df octree:
if (node.firstChild >= 0)
{
int octant = node.GetOctant(particlePosition);
return(DFTraverse(particlePosition, node.firstChild + octant, ref header, ref dfNodes));
}
else
{
return(node.SampleWithGradient(particlePosition));
}
}