Game Development Reference
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(a) Tiled shading
(b) Clustered shading
Figure 4.5. Comparison between volumes created by (a) the tiling explored in this
article and (b) clustering, as described in [Olsson et al. 12b]. Finding the tiled vol-
umes is relatively simple and can be done in standard fragment shaders. Clustering is
implemented with compute shaders, as is the light assignment to clusters.
fact, in some cases it offsets time won in the shading from the better light-to-
sample mapping offered by clustering (Figure 4.6). We are also further exploring
clustered forward shading [Olsson et al. 12a], which shows good promise on mod-
ern high-end GPUs with compute shader capabilities. Tiled forward shading, on
the other hand, is implementable on a much wider range of hardware.
Figure 4.6. Comparison between tiled forward shading and clustered forward shad-
ing. (a) In the top-down view, tiled forward outperforms our current clustered forward
implementation (6 . 6msversus9 . 3 ms). (b) In the first-person-like view, tiled forward
becomes slightly slower (9 . 4msversus9 . 1 ms). While somewhat slower in the first view,
one of the main features of clustered shading is its robust performance. There are 1,024
randomly placed light sources.