public override void IntersectLocal(ref Tuple origin, ref Tuple direction, Intersections intersections)
{
Intersections leftXs = new Intersections();
Left.Intersect(ref origin, ref direction, leftXs);
var rightXs = new Intersections();
Right.Intersect(ref origin, ref direction, rightXs);
Intersections result;
if (leftXs.Any() || rightXs.Any())
{
var xs = new Intersections(leftXs.Concat(rightXs));
result = Filter(xs);
intersections.AddRange(result);
}
}