Baking and uv / prop construction advice

decorix

Hello All,

I'm currently doing a machine part design with lots of cylinder shapes.

Instead of having Cylinder and extruding with /bevels/chamfers. I'm using

seperate cylinders for each section of the canister. This makes changing stuff more easier as

you can scale/move/parts adjust thing on the fly. I only need to make a more advanced highpoly version of

the LP_Cylinders.

When I have unwrapped all my LP_Cylinders Can I attach them all together as one mesh?

Or would it be wise not to attach them? I'm usng SP for baking with _LP / HP suffix

so I don't need to explode them. I'm not sure what would happen with baking if its only one mesh for LP

and one mesh for the HP :-)

The problem is that the Canister is part of the machine. So it still needs to be positioned as well.
I could group both LP and HP meshes and then bring them in position.

Any ideas welcome just wanne save my self some time if i'm making it hard on my self :-)

Cheers

Ghogiel

There's no need to attach them. Just add a single material to them. Name each separate high poly object so that it corresponds to an appropriete low poly part. Name matching in the bake settings in substance should help avoiding some intersecting errors in the bake.

sprunghunt

You're wasting a lot of texture resolution by leaving your lowpoly pieces as separate shells. If you can't see part of the mesh in the final lowpoly you shouldn't have polygons there. This kind of construction also causes problems with lightmaps and other systems in-game. 

rollin

sprunghunt said:

You're wasting a lot of texture resolution by leaving your lowpoly pieces as separate shells. If you can't see part of the mesh in the final lowpoly you shouldn't have polygons there. This kind of construction also causes problems with lightmaps and other systems in-game. 

But what if this is a kit which will be reused and re-combined in various ways?

sprunghunt

rollin said:

sprunghunt said:

You're wasting a lot of texture resolution by leaving your lowpoly pieces as separate shells. If you can't see part of the mesh in the final lowpoly you shouldn't have polygons there. This kind of construction also causes problems with lightmaps and other systems in-game. 

But what if this is a kit which will be reused and re-combined in various ways?

Even then you should avoid doing this. 

Keep in mind that when you bake this mesh it will put shadows in the ambient occlusion map where parts overlap. 

If you want to be able to randomly combine the cog pieces with the shaft later you should explode the mesh so it doesn't put shadows on the shaft.

decorix

Thank you all for helping out. Last night I did some fast testing. I did exactly what I was

planning to do and what "Ghogiel" also mentioned. LP_to HP conversion and baking LP and HP model in SP.

I think everything is oke and the bake turned ok considering it was a fast UV job:-)

I do want to save on uv space, with my duplicated meshes, but thats the next step.

I can't see any problems with my intersection cylinder shape meshes? I can adjust it very fast and make

adjustments on the fly. If I would have it as one mesh with extrudes and bevel it would be also alot

harder to UV. The assembly part on the screensho is only small part of the entire mesh. Perhaps
even having two texture sets/material ids.

Because its complex mesh with lots of things tubes,cylinders,bolts,etc. It gonne be alot uv work..pfff

packing and getting the most out texture density.

Perhaps I should still do fast test export out the LP model with uv for my lightmaps (unreal) to see

if i run into any problems.

Can I move on? and start:-)

sprunghunt

decorix said:

Thank you all for helping out. Last night I did some fast testing. I did exactly what I was

planning to do and what "Ghogiel" also mentioned. LP_to HP conversion and baking LP and HP model in SP.

I think everything is oke and the bake turned ok considering it was a fast UV job:-)

I do want to save on uv space, with my duplicated meshes, but thats the next step.

I can't see any problems with my intersection cylinder shape meshes? I can adjust it very fast and make

adjustments on the fly. If I would have it as one mesh with extrudes and bevel it would be also alot

harder to UV. The assembly part on the screensho is only small part of the entire mesh. Perhaps
even having two texture sets/material ids.

Because its complex mesh with lots of things tubes,cylinders,bolts,etc. It gonne be alot uv work..pfff

packing and getting the most out texture density.

Perhaps I should still do fast test export out the LP model with uv for my lightmaps (unreal) to see

if i run into any problems.

Can I move on? and start:-)

You baked from a hipoly but it looks like you don't have any ambient occlusion or curvature? I guess if that's the style you're going for then this is fine. 

But normally for realistic texturing the point of using tools like Substance Designer is to be able to use the information from those maps to quickly apply dirt, edge wear, and other texturing effects. This is where having overlapping UV's doesn't work well. 

Kanni3d

@sprunghunt - if he were to bake AO etc, he would have issues moving those elements and parts around. He likely has AO baked exploded/by groups, and your just seeing a base color material in that substance viewport.

The only issue is your occluded parts are simply wasting texture space as they aren't seen. However, if you're using this in a 'kitbashing' fashion,it would be totally fine. You would have some instances of faces being totally wasted/occluded/not visible, and some instances where those same faces would be visible.

decorix

sprunghunt said:

You're wasting a lot of texture resolution by leaving your lowpoly pieces as separate shells. If you can't see part of the mesh in the final lowpoly you shouldn't have polygons there. This kind of construction also causes problems with lightmaps and other systems in-game. 

Hi, still busy with testing stuff here. Question  what If I delete the hidden poly's/caps of the cylinders that aren't seen any way to save on uv space. I'm baking with match by name in SP so NO  AO baking problems. I still think you can prototype shapes much faster also the unwrap is much faster.  I think it should work fine this way. Let me know if you still see any problems. Thanks