BUG: Redundant UV Maps

[Donovan Keith]

Imports 8 UVW maps every time. No matter if you have custom UVs or not.

• [ ] When fixed, please tweet @YunalSobu

[Moritz Weller]

plz notify me on twitter, too when this is fixed, thx! @moritzw

[Leo “Leho” Horovitz]

I'm working on this now. I took over the development of this plugin from a previous programmer so there are still some things where I have to do some detective work. It turns out the Cinema4D plugin just sends one UV channel while the Unreal plugin always creates 8. I'm going to fix it so that Cinema sends as many as are used, capped at Unreal's maximum of 8, and then the Unreal plugin uses those. I noticed though that Unreal seems to have a minimum of 2 UV channels since if I just create 1 in the code, there are still 2 UV channels when I inspect the mesh. And if I just create a standard cube mesh it gets 2 UV channels by default. So it will be a minimum of 2 and a maximum of 8 and then somewhere in between depending on how many are used in Cinema4D.

[Donovan Keith]

Not sure, but I think Unreal uses one UV Map for texturing and the other for light maps. It might make sense to auto-generate a non-overlapping UV Map using C4D's UV commands if a lightmap UV Set doesn't exist.

[Leo “Leho” Horovitz]

Just wanted to let you know that I'm continuing to work on this. Trying to figure some things out, I'm going to continue working today and during the weekend.

[Moritz Weller]

Fyi: UE4 does also support 1 single UV. It‘s an option in the import dialog to automatically add an additional UV slot "1" (instead of only "0") with automatically generated lightmap UVs. I would prefer to be able to control this behaviour, e.g. to choose either to import 2 custom uv sets from c4d or import only 1 and additionally generate lightmaps on import into UE4

[Donovan Keith]

Possibly related request:

• Lightmap not exported If you make 2 UVWs, one for texture and one for Lightmap, UE goes systematically recompute Lightmap from last UVW.

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