private void FillWithLeaves(AlphaBlockCollection tree, int y)
{
int distanceFromTop = tree.YDim - y;
uint size = 1u + (uint)distanceFromTop * 2u;
tree.Fill(new BoundingBox(new Position((tree.XDim - (int)size) / 2, y, (tree.ZDim - (int)size) / 2), size, 1u, size), _leafId);
}
