Circuitry for identifying a closest intersected bounding volume in a target grid in a 3-dimensional scene includes circuitry that generates grid coordinates of candidate x-, y-, and z-planes in the target grid that belong to bounding volumes and which are closest to the ray. Comparator circuitry determines the closest plane among the candidate x-, y-, and z-planes to the ray. Circuitry generates an identifier of the bounding volume using the grid coordinates of the closest plane. The allocation of resources for some components comprising the circuitry is based on the number of planes that define the target grid, and for other components of the circuitry is based on the number of bounding volumes being considered.