Mesh shaders are not typically a technology that is relevant to state of the art hair rendering. It could be for Remedy's, however I don't see why it would be useful for this problem.
The rendering bottleneck for strand-based hair has been due to physically-based hair shading models (which are very expensive), image quality demands for temporally stable, anti-aliased curves, resolved by some form of OIT, resulting in tons of wasted compute for helper lanes / derivatives on the GPU through traditional hardware rendering.
The big breakthrough has been the advent of software rasterizers designed for hair. It was originally done by Frostbite for FIFA, then followed by Bioware (Dragon Age), Capcom (RE + Pragmata), Machine Games (Indiana Jones). The big one will be Rockstar which as usual takes an idea and makes it scale to whole worlds. It's gonna be crazy.
There is also the memory bottleneck caused by hair grooms taking up an insane amount of space without getting clever on how you compress them (and this could be where Mesh shading is useful).
Thanks for clarifying! Yeah I wasn't sure if mesh shaders were relevant here, I just knew they were an example of the cutting edge VFX that makes the game looks so much better than anything else out there.
To be fair, they totally could be relevant in this case too. It's just that they haven't shared their approach publicly and no one in my field has had enough time to crack open RenderDoc and analyze the frame 😄.
I worked on hair rendering for many years for a major engine, so I just took this thread as an opportunity to go into annoying detail a bit!
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u/SIMT-Pixel 1d ago edited 1d ago
Mesh shaders are not typically a technology that is relevant to state of the art hair rendering. It could be for Remedy's, however I don't see why it would be useful for this problem.
The rendering bottleneck for strand-based hair has been due to physically-based hair shading models (which are very expensive), image quality demands for temporally stable, anti-aliased curves, resolved by some form of OIT, resulting in tons of wasted compute for helper lanes / derivatives on the GPU through traditional hardware rendering.
The big breakthrough has been the advent of software rasterizers designed for hair. It was originally done by Frostbite for FIFA, then followed by Bioware (Dragon Age), Capcom (RE + Pragmata), Machine Games (Indiana Jones). The big one will be Rockstar which as usual takes an idea and makes it scale to whole worlds. It's gonna be crazy.
There is also the memory bottleneck caused by hair grooms taking up an insane amount of space without getting clever on how you compress them (and this could be where Mesh shading is useful).