A Hierarchical Primitive Lists Structure for Tile-Based Rendering

Tile-based rendering has been widely used inresource-limited graphic processing environments, e.g., forhand-held devices. Since large primitives may cover a significantnumber of tiles, they need to be recorded in the primitive lists ofall related tiles. We propose a hierarchical primitive listsstructure, which also copes with misaligned and non-squareprimitive problems, to minimize the primitive recording.Intended advantages include: reduced storage pressure, listbuilding time, primitive retrieval counts for subsequentrendering, primitive data accesses (from external memory)during rendering, and possibly enhanced data locality/resourceutilization if layer-based rendering is exploited. Based on thisstructure, we propose a primitive-hierarchy fitting (hardware)algorithm which, for a given primitive of any size and shape,determines a best way of storing it in the structure. Experimentalresults on Doom3 and Quake4 show 10% to 33% storagereduction with our full capability, compared with using squarehierarchies only.