Deep g-buffers for stable global illumination approximation
Michael W. Mara, Morgan McGuire, Derek Nowrouzezahrai, David P. Luebke · High Performance Graphics · 2016
We introduce a new hardware-accelerated method for constructing Deep G-buffers that is 2x-8x faster than the previous depth-peeling method and produces more stable results. We then build several high-performance shading algorithms atop our representation, including dynamic diffuse interreflection, ambient occlusion (AO), and screen-space mirror reflection effects. Our construction method is order-independent, guarantees a minimum separation between layers, operates in a (small) bounded memory footprint, and does not require per-pixel sorting. Moreover, addressing the increasingly expensive cost of pre-rasterization, our approach requires only a single pass over the scene geometry. We include the pseudocode for our Deep G-buffer construction in the paper and the full source code of our technique in our supplemental document.