Abstract: Multi-fragment effects such as real-time transparency are rendered by visiting the per-pixel fragments in depth order. The k-buffer algorithm rendered the scene in a single pass to obtain several layers of fragments. The read-modify-write hazard while updating the buffer should be avoided thus the performance was likely to be hit hard. The temporal and spatial coherence among frames were exploited to cull the input fragments in an online manner. A fragment cache based on a semi-heap was proposed. The worst case scenario of the time complexity was analyzed. The reverse reprojection was employed to construct the culling interface on the fly while rendering a frame. Since the buffer updating operations are effectively reduced and no preprocessing is required, the complexity scene during walkthrough or changing can be rendered efficiently.

Key words: depth peeling, heap sort, fragment interlock, reverse reprojection