| abstract |
A scene 50 to be rendered is divided into plural individual sub-regions or tiles 51. The individual sub-regions 51 are also grouped into differing groups of sets of plural sub-regions. There is a top level layer comprising a set 54 of 8 x 8 sub-regions which encompasses the entire scene area 50. There is then a group of four 4 x 4 sets of sub-regions 53, then a group of sixteen 2 x 2 sets of sub-regions 52, and finally a layer comprising the 64 single sub-regions 51. A primitive list building unit takes each primitive 80 in turn, determines a location for that primitive, compares the primitive's location with the locations of the sub-regions 51 and the locations of the sets of sub-regions 52, 53 and 54, and allocates the primitive to respective primitive lists for both the sub-regions and sets of sub-regions accordingly. |