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How to make materials look great in VR?

I have reading the presentations from Nick and Nick in Oculus Connect. Lot of info there, but I haven’t clear enough how to achieve some of the techniques they share. Normal maps in materials aren’t good, we all see it, and they talk about going to older solutions like bump offsets. So could anyone share here what are they talking about and how to set up that type of materials in the Unreal material editor? I am intrigued specially in how to do a brick wall or stone pavement look great in VR without going to a high dense polygon static mesh.

Going further, this is for Epic: would be a chance to have a small VR demo were all the workarounds, tricks and ideas shown in OC be demoed and sampled? The fake shadows in the Showdown demo looks promising, and all other stuff is also awesome and a really need to go for a 90fps experience.

The starter content materials actually use bumpOffset in their shader networks - check out the brick and cobblestone materials for how to set these up.

As for getting stuff to look great - photos. Use as much photographic elements in your textures as you possibly can. Procedurals can help break up non-tiling textures. But the fact is, relying on premade textures will only lead to a less believable looking end-product (if of course photorealism is the look you’re going for, as opposed to cartoony)

Can someone explain how/why normal maps don’t look good in VR? I haven’t noticed a big problem… but I never thought normal maps looked very good in 2D, either;)

It’s just that the blockiness of or lack of geometry is really obvious once you have depth perception.

So it’s not that normal maps don’t work. They do exactly what they have always done. It’s what they don’t do (add geometric details) that becomes more obvious.

They work perfectly fine for surface details but once you get relativly close to an object you aren’t going to fool the player that your flat wall has bricks pertruding from it.

For models baked from a highpoly you will have to worry a bit more about concave details on the lowpoly model than before. Before you could get away with less polygons in concave areas as long as you had a nice silhouette.

I think in general from what I have tested so far I don’t see any major problems with using normal maps. You’ll notice when you need to add extra geometry.

Yes, thanks for the replies. I have been doing some tests. It feels me that some things work wonderful, as giving a wood material some kind of loose of the varnish using that typical aproach of using a macro texture variation that uses Epic a lot and asigning then it in the roughness, so you have some random zones in the material more rough and other more shiny.

The Starter content is great and I am studying what works best. But as far as I could test till now bricks or walls materials work relatively well with that normals that Epic use. I have seen in a material a BumpOffset node. I am no sure what this does, I have to check it better, but I think improves the material in VR.

Other materials, as some of them they have in Starter content that are suitable for rocky floor, I do not know why, but do not work at all. I think this is more a matter of the point of view of the camera (that is mimicking the human eyes) than what type of modifier you add to the material. Materials that add variation in a very small scale, as the wood roughness, work pretty well specially when you get close. Normals are better if you see them far from you and standing up (in walls for example), but when you get closed the illusion goes off. And finally in the ground there isnt any way, at least I haven’t found it, to really notice the bump or the variations, perhaps because looking from up to down makes anything loose the illusion. So I am fraid in this last case we will need to go to a densification of details, placing more vegetation, or sth like that.

Anyone with more expertize can clarify me if I am on the correct ideas?

From what I’ve been able to piece together, the current generation of VR is not going to provide the “great” experience you guys are describing. Everything from Carmack & the Oculus team is saying they suggest lowering the fidelity and sacrificing beauty for framerate, and thats primarily because the responsiveness matters so much to good immersion and avoiding nausea. I will admit that normal maps alone aren’t the prettiest solution, but while we are still grasping at straws about what the consumer devices will be able to do, let alone being able to foresee what VR is going to do in the market, worrying about fidelity is not exactly justified.

That said, You can still pull off most of the tricks that Unreal has been so good at hiding from us over the years, and as we get closer to the consumer version of the rift we will likely see more from the Oculus community and team on this very topic.

Thanks for the explanation! Time for more dynamic tessellation! :wink: