Coarse-Z Filter:降低深度带宽的图形流水单元  

Coarse-Z Filter:a Graphics Pipeline Unit to Reduce Depth Bandwidth

作　　者：高可[1] 杨珂[1] 石教英[1] 刘真[1] 

机构地区：[1]浙江大学CAD&CG国家重点实验室,杭州310027

出　　处：《计算机辅助设计与图形学学报》2006年第11期1658-1663,共6页Journal of Computer-Aided Design & Computer Graphics

基　　金：国家自然科学基金(60533080)

摘　　要：提出Coarse-Z Filter（CZF）图形流水单元,在像素级深度测试前进行Tile级深度测试,以减少读Z-Buffer的次数,从而有效地降低图形流水线的带宽.CZF提供单缓存和双缓存2种模式,前者由一个低分辨率过滤缓存组成,存储扫描转换后Tile内所有采样点的最大深度值;后者增加了一个辅助缓存和掩码位平面,以获得更高的剔除效率.测试结果表明,在当前渐趋复杂的场景中,使用CZF可降低30%～40%的带宽.We proposed a graphics pipeline unit, namely Coarse-Z filter （CZF）, for tile-level depth culling prior to per-pixel test, to reduce depth reading and thus reduce the pipeline bandwidth. CZF provides two modes, namely Single CZF, which employs a low-resolution Filter Buffer storing the maximum depth of a scan-converted tile; and Double CZF, which adds an auxiliary buffer and a bit mask plane to gain a higher culling ratio. Test results shows that CZF can reduce up to 30% -40% pipeline bandwidth in today＇s scenes being more complex.

关 键 词：图形流水线 深度缓存 片 Coarse-Z FILTER 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]