| 摘要 |
<p>A method and apparatus for rendering an object or scene from a preselected viewpoint onto a display. The object is represented by a texture map stored in a memory of a processor-based system, and the viewpoint is represented by geometry data stored in the memory. The viewpoint on the object may be represented in the geometry data a polygon (or more than one polygon). The processor determines span data by edge-walking the polygon, and transfers the span data to the memory controller. Beginning with a first such span, the processor then transfers the span data (one span at a time) to the memory controller. After each such transfer, the memory controller takes over execution of the rendering procedure, beginning with mapping the current span onto a span of voxels (volume elements) in texture map space. The memory controller then retrieves the colors and textures for that span, and renders the span accordingly (i.e. either displays it or writes it to an appropriate memory). Control then returns to the processor, which transfers the data for the next span, and the memory controller again takes over the remainder of the rendering procedure for that span. The transfer of control back and forth is repeated until all the spans of the first such polygon are rendered, and until all such polygons have been so processed, thus greatly increasing the efficiency and throughput of graphics data in the rendering pipeline. The procedure is made more efficient by the use of a dedicated portion of memory for the graphics data, under the exclusive control of the memory controller. <IMAGE></p> |
