protected bool _perInstanceIntersectionTest(SSAbstractMesh abstrMesh, int i,
ref SSRay localRay, out float localContact)
{
var pos = instanceData.readPosition(i);
var masterScale = instanceData.readMasterScale(i);
var scale = instanceData.readComponentScale(i) * masterScale;
if (abstrMesh == null)
{
// no way to be any more precise except hitting a generic sphere
float radius = Math.Max(scale.Z, Math.Max(scale.X, scale.Y));
var sphere = new SSSphere(pos, radius);
return(sphere.IntersectsRay(ref localRay, out localContact));
}
else
{
// When using SSAbstractMesh we can invoke its preciseIntersect()
Matrix4 instanceMat = Matrix4.CreateScale(scale) * Matrix4.CreateTranslation(pos);
SSRay instanceRay = localRay.Transformed(instanceMat.Inverted());
float instanceContact;
if (abstrMesh.preciseIntersect(ref instanceRay, out instanceContact))
{
Vector3 instanceContactPt = instanceRay.pos + instanceContact * instanceRay.dir;
Vector3 localContactPt = Vector3.Transform(instanceContactPt, instanceMat);
localContact = (localContactPt - localRay.pos).Length;
return(true);
}
else
{
localContact = float.PositiveInfinity;
return(false);
}
}
}
