private HitPoint GetHitPointR(Vector3 d, Vector3 OP, BVHNode node)
{
if (node.Left != null && node.Right != null)
{
float lambdaLeft = Helper.VectorSphereHitPoint(d, OP, _spheres[node.Left.SphereIndex]);
float lambdaRight = Helper.VectorSphereHitPoint(d, OP, _spheres[node.Right.SphereIndex]);
if (lambdaLeft == HitPoint.NoHitPoint.Lambda && lambdaRight == HitPoint.NoHitPoint.Lambda)
{
return(HitPoint.NoHitPoint);
}
else if (lambdaLeft != HitPoint.NoHitPoint.Lambda && lambdaRight != HitPoint.NoHitPoint.Lambda)
{
HitPoint hpLeft = GetHitPointR(d, OP, node.Left);
HitPoint hpRight = GetHitPointR(d, OP, node.Right);
return((hpLeft.Lambda < hpRight.Lambda) ? hpLeft : hpRight);
}
else if (lambdaLeft != HitPoint.NoHitPoint.Lambda)
{
return(GetHitPointR(d, OP, node.Left));
}
else // lambdaRight != HitPoint.NoHitPoint.Lambda
{
return(GetHitPointR(d, OP, node.Right));
}
}
else
{
Debug.Assert(node.SphereIndex < _naturalSpheresCount);
float lambda = Helper.VectorSphereHitPoint(d, OP, _spheres[node.SphereIndex]);
if (lambda == HitPoint.NoHitPoint.Lambda)
{
return(HitPoint.NoHitPoint);
}
else
{
return(new HitPoint(OP, lambda, d, node.SphereIndex));
}
}
}
public BVHAccelerationStructure(List <Sphere> spheres)
{
_spheres = new Sphere[spheres.Count * 2];
_naturalSpheresCount = spheres.Count;
_root = Populate(spheres);
}
public BVHNode(BVHNode l, BVHNode r, int sphere)
{
Left = l;
Right = r;
SphereIndex = sphere;
}