Patent ID: 8817026

Claim:
A method in a ray traversal unit comprising digital logic circuits, the method comprising the digital logic circuits: storing in a data store ray data representative of a plurality of rays traversed through a scene, the scene being partitioned into a hierarchy of cells, the ray data including, for each ray, a hierarchy of dirty cells intersected by said each ray, the ray data being grouped according to intersected dirty cells at a first level in the hierarchy (“first level dirty cells”); receiving from the data store ray data representative of a group of first rays which intersect a given first level dirty cell; sorting the received ray data according to dirty cells in a second level in the hierarchy (“second level dirty cells”) and dirty cells in a third level in the hierarchy (“third level dirty cells”); processing the sorted ray data for ray/object intersections, and when a given ray intersects an object then: completing processing of the given ray concurrently with launching one or more new rays from the given ray; traversing the one or more new rays through the scene; and when one of the new rays intersects a dirty cell at an n th level in the hierarchy, then storing ray data of said one of the new rays in the data store including data representative of a hierarchy of dirty cells that contain the n th level dirty cell.