Best workflow for hard surface in UE5?

Nerdicon3000

I was thinking of doing a Sci-fi scene in UE5 and was just wondering if there was a way to take advantage of nanite doing hard surface modelling. I see how it's beneficial for the kind of giant organic pieces they used in their demos but I was wondering if anyone has created a scene just importing high poly hard surface assets and if so what kind of workflow did they use for materials and stuff.

Maybe I should just stick to the old techniques and see how lumen goes?

Axi5

Hi Nerdicon,

The developer behind Nanite showed off that it works with hard surface models just as well as organic. This was also one of the first things I tried by throwing some Sub-d models into UE5 and they came out great. Model to your hearts content. UV and Material "rules" haven't changed much just do what you used to.

Nerdicon3000

Yeah I watched that, the bike yeah? To me that didn't look that great. It was a high poly model with 3 very basic shaders on it. To make it look good you would need to properly texture it like the other models in the scene and wouldn't that kind of defeat the purpose of the high poly model? 

oglu

Clean modeled highpoly is not a dynames like mesh. Its clean modeling just without a poly limit. Do a bevel with 5 segments if you need a clean edge. Modeling like you would do for product viz.

Even a converted Fusion 360 mesh would work. 

Alex_J

the individual segments of the chain were modeled. Can't do that with a texture. 

I didn't watch whole video but I think the point they are making is that because the rendering of triangles is so much faster, sometimes instead of using extra normal maps you can just use geo instead and it's cheaper + makes better silhouette and lighting.

I don't think there is any serious workflow changes for artist, except maybe not doing as much LOD's and some models can use extra geo instead of baking a normal map (or normal map is used for fine details only.)

Axi5

Nerdicon3000 said:

Yeah I watched that, the bike yeah? To me that didn't look that great. It was a high poly model with 3 very basic shaders on it. To make it look good you would need to properly texture it like the other models in the scene and wouldn't that kind of defeat the purpose of the high poly model? 

To make the most of Unreal's new workflow you should be using virtualised textures anyway. Just do as you did before, but where you would have used a normal map before just throw more geometry at it, that's the intention behind Nanite.

As others said here, bevels, Fusion360 these are all your friends now. If you want it to sing you'll probably still need to unwrap it and texture it somehow, but Substance and other tools are helpful in this situation.

sprunghunt

The tricky part is going to be the texturing. I'm not sure how easy it'll be to texture a hi-poly model in substance designer. Epic said they were using Mari - which the film industry likes to use because it handles hi-poly models better. 

Has anyone done any tests in Substance painter to see how hi-poly a model it can handle? 

This is an interesting approach - there's no textures in the scene below - it's all vertex color: 
https://www.artstation.com/artwork/XnQGaw

oglu

I painted some assets around 500k in painter and it was m anageable but slow. I wont recommend that in production. 

Nerdicon3000

Thanks for the advice guys! I guess what I'm confused about is the texture workflow. Like if you want to add grime or decals or anything with a change of colour or roughness really you will need to do the old fashioned unwrap and painting a high poly mesh is a bitch. I might just stick to the old fashioned workflow for now,

gnoop

 Mari is gonna have sales increase      Lets hope they will be able to drop the price because of this

poopipe

you're not going to need massive unique textures when you have the geometry to back them up. 
RVT allows for UDIMS, you can use tileables and masks .  etc etc. 

you just have to actually think about what you're doing instead of smashing autounwrap and throwing it at painter. 

Painter can work on very high res assets - it's texture resolution that knackers it

sprunghunt

poopipe said:

you're not going to need massive unique textures when you have the geometry to back them up. 
RVT allows for UDIMS, you can use tileables and masks .  etc etc. 

you just have to actually think about what you're doing instead of smashing autounwrap and throwing it at painter. 

Painter can work on very high res assets - it's texture resolution that knackers it

Yes - when I make things for an offline renderer (like mentalray) I don't use nearly as many unique painted textures. It's all about blending together tiled textures in various ways. 

Nerdicon3000

Ok, I will try it with tileables and masks. I just thought using high poly assets was meant to make your life easier, but unwraping a high poly mesh for tileable textures sounds like it won't be so easy. Also do decals work on nanite meshes? Otherwise I don't see how you cant use unique textures to do basic hard surface decal stuff like text etc.

poopipe

Nanite is not designed to make your life easy, it's designed to support much higher fidelity assets at a reasonable level of performance than would be achievable using previous methods. 

RVT should allow you to bake projected decals etc. into surfaces.  Whether it's turned on yet for Nanite or not is another matter

Axi5

poopipe said:

you just have to actually think about what you're doing instead of smashing autounwrap and throwing it at painter. 

I tried this the other day and it worked really well so... "I'm in this picture and I don't like it" haha

poopipe said:

Nanite is not designed to make your life easy, it's designed to support much higher fidelity assets at a reasonable level of performance than would be achievable using previous methods. 

RVT should allow you to bake projected decals etc. into surfaces.  Whether it's turned on yet for Nanite or not is another matter

According to the docs, it's recommended to use virtual textures alongside Nanite, so I expect RVT and SVT to work. Edit: Oh I see you just meant decals, I haven't tried that yet.

And I mean, Nanite is designed to make your life easier, but what we do is never easy

ZacD

I really need to experiment more but my general thoughts are:

Definitely experiment using vertex RGB for base color and the alpha for roughness. 

If you want to use Substance Painter and Nanite, really seems like subdivision modeling might be the way to go. Make a model that subdivides well without edges sliding around too much (evenly spaced edge loops instead of just loops by edges). Unwrap the unsubdivided version, paint either subdiv 0 or 1. Subdivide model in UE5 using the modeling tools. 

Experiment with texturing that's driven by triplanar materials and masks.