OCCLUSION CULLING FOR COMPLEX TRANSPARENT SCENES IN COMPUTER GENERATED GRAPHICS

摘要

A method of and apparatus for efficiently rendering a complex transparent scene. In furtherance of one embodiment of the present invention, the method comprises the step of determining a minimum number of overlapping translucent polygons required to substantially occlude an object or a surface in the scene; and culling away the object or the surface if the object is hidden behind more than the minimum number of overlapping polygons. Objectives of the present invention are achieved as processing efficiency is increased when substantially occluded objects are not further processed. In one embodiment of the invention, a Z-stack comprising a plurality of Z-maps is utilized to store depth information of potentially occluding polygons. A bounded volume approximation method may be used to determine the Z-values of the potentially occluding polygons to be stored in the Z-stack. Thereafter, potentially occluded polygons are tested against the Z-stack. Visibility is determined based on a comparison of the Z-values of the potentially occluded polygons and the Z-values in the Z-stack.