// Stack for nodes that need to be processed
// Start with root at first node
int stack[32];
stack[0] = 0;

int stackptr = 0;
int node = 0;

do
{
    // Fetch children and check overlap of both
    ivec2 children = ivec2 (texelFetch (Light_BVHChildrenNodes, node).rg);
    bvec2 overlap = bvec2 (IsOverlapping (children.x, depths, tilerect), IsOverlapping (children.y, depths, tilerect));

    // Increment light count for this cluster if node is a leaf
    if (overlap.x && children.x > LightCount) ++count;
    if (overlap.y && children.y > LightCount) ++count;

    // Tree needs to be traversed if the child is not a leaf and overlapping eith the cluster
    bvec2 traverse = bvec2 (overlap.x && children.x < LightCount, overlap.y && children.y < LightCount);
    if (any (traverse))
    {
        // Go on to the next child, if both childs need traversal save the other one on the stack
        node = (traverse.x) ? children.x : children.y;
        if (traverse.x && traverse.y)
            stack[++stackptr] = children.y;
    }
    else
    {
        // Children need no traversal, pop the next node from the stack
        node = stack[stackptr--];
    }
} while (node != 0);