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Normal Maps / Tesselation - your experiences?

Hi fellow VR’rs,

today I was toying around with a high poly character model. It’s kind of a monster/troll/goblin with a scaly skin.

The skin looks really great in non-vr view with normal maps. But with the rift on, the whole character looks too smooth and unrealistic from near.

So I tried tesselation. But even after a lot of finetuning and different values I could not get a VR view that was that much better to justify using tesselation. Tesselation even introduced new problems, like seams between head/face textures.

So I couldn’t get a good result for VR with either approach.

Do you have any experiences? How do/did you handle the uncanny valley?

Greetings,
Ben

I don’t think VR has any effect on tesselation, it’s probably just a general issue. There’s some settings in the material you can adjust but the displacement also has to be correct in the first place.

I’m doing some testing on tessellation and VR. I use it in my VR game for scene geometry like walls. You can see my vids from my blog in my Signature. I think normal maps for large detail in VR are no longer good practice. For micro detail they still work great. When building models for VR games you need to separate out areas for tessellation and the areas that don’t. For example if you see the door in my last video in my blog, you can see raised rivets around the door frame. These are currently done in normal map but if you get close and at an angle in VR then the effect falls over and it looks flat even though the lighting is trying to make it look raised. However the dirt and scratches look fine. I am remodeling the door with separate parts for the rivets that I will apply a tessellation material and height map to this means the whole door won’t need to tessellate. This should make the effect much better. I think there will be a lot of areas like this in VR that asset creation artist will have to rethink in order to make them look good in VR. I don’t know if my approach is the most efficient but its very early days with VR trying to make this stuff look right.

Your results look awesome Mrob76u!

I think the issue raised in this thread is more about how to actually go about setting up tessellation materials so that they work correctly (at least, that’s my problem). Got any tips?

If you check my blog there is a link to the materials Tutorials I used and the graph of the Tessellation setup for the materials

I’m curious, do folks have a threshold or set of criteria at which they just use a higher poly model to begin with? In other words, instead of burning GPU to create fake vertices with tessellation, you burn GPU by having more triangles to begin with?

I can think of a few items to consider but was wondering if there’s any more?

  • Tessellated geometry is not part of the mesh and would not get collision detection etc. If you expect collisions to occur here don’t use tessellation?
  • High polygon models, while having more detail, still don’t end up looking right because self-shadowing and lighting doesn’t get into the small places/crevices well enough so normal/POM maps would still be necessary anyhow?
  • [edit] POM, while themselves are complex shaders which burn GPU, are still faster (and nearly just as good) than the above 2 possibilities so consider those first?

Oh neat, didn’t see that. Thanks :slight_smile: