GPU Pro 5

246 III Image Space

Figure 3.8. CoC across the framebuffer.

Now, depending on the platform you are developing for, this process can be

done by different work units. On DX11, all this is realized in the compute shader

with the color and depth buffer used as textures. On PS3, we don’t have this

stage available, but we do have the SPUs!

3.4 Let’s SPUify This!

On PS3 the memory is split in two: main and video memory. Typical pipelines

have the main color buffer placed in video memory for performance and memory

footprint reasons. Since the SPUs like to work on buffers placed in main memory

(read/write mode), the first step is to transfer the main color buffer int ...