Masked Depth Culling for Graphics Hardware
To appear in SIGGRAPH Asia 2015.
Abstract
Hierarchical depth culling is an important optimization, which is present in all modern high performance graphics processors. We present a novel culling algorithm based on a layered depth representation, with a per-sample mask indicating which layer each sample belongs to. Our algorithm is feed forward in nature in contrast to previous work, which rely on a delayed feedback loop. It is simple to implement and has fewer constraints than competing algorithms, which makes it easier to load-balance a hardware architecture. Compared to previous work our algorithm performs very well, and it will often reach over 90% of the efficiency of an optimal culling oracle. Furthermore, we can reduce bandwidth by up to 16% by compressing the hierarchical depth buffer.