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Old 02-08-12, 01:23 AM   #299
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Join Date: Mar 2006
Posts: 532
Default Re: next gen kepler to support dx 11.1, also take a year to rollout all cards

Originally Posted by Vardant View Post
It was because of displace mapping/height mapping. For example, if you have a 128x128 texture, tesselation needs to smooth the polygon to 128x128 or more polygons.

If you go even further to 256x256, it allows for smoother transitions and the object appears much more plastic, thanks to tessellation and displace/height mapping.
If this is the case they have problem on how they are tesselating the objects.
They should use view dependent tesselation in which case you can use error metrics to decide how many polygons are needed. (by curvature, pixel/polygon size in screenspace and so on.)

Originally Posted by Vardant View Post
The other reason, for almost over-using tessellation is a problem with very thin and long polygons. The GPU has a really hard time with dealing with polygons, that are for example only 1mm wide, but 5m long. It's a problem, that every engine he worked on had. Dynamic tessellation on singlemesh objects should help with that, but Crysis 2 apparently doesn't support it. And because it's missing, the level of tessellation doesn't change with the distance of camera.
This would be a case where view dependent tesselation would help a lot, but art should be made with tesselation in mind as well.

I really hope that we would see a proper case for tesselation in some future game.
Mesh prepared so that it would have decently even structure, using vector displacement mapping and texturing which has UVWs relaxed properly, so it will not stretch with the dispalcement.
jlippo is offline   Reply With Quote