A Hierarchical Primitive Lists Structure for Tile-Based Rendering

Tile-based rendering has been widely used in resource-limited graphic processing environments, e.g., for hand-held devices. Since large primitives may cover a significant number of tiles, they need to be recorded in the primitive lists of all related tiles. We propose a hierarchical primitive lists structure, which also copes with misaligned and non-square primitive problems, to minimize the primitive recording.Intended advantages include: reduced storage pressure, list building time, primitive retrieval counts for subsequent rendering, primitive data accesses (from external memory)during rendering, and possibly enhanced data locality/resource utilization if layer-based rendering is exploited. Based on this structure, 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. Experimental results on Doom3 and Quake4 show 10% to 33% storage reduction with our full capability, compared with using square hierarchies only.