Lightmap overlapping

I think I read bunch of this posts still dont get it :frowning: I have done in max unwrap on model, second channel, then moved to channel one. Stil in UE it show uv overlapping do I have to convert it to mesh or poly every time I do unwrap?

I guess there is somewhere a face that shows up as a line, because it is unwrapped “edge on”…
Also, there are a lot of small chunks that should be cleaned up a bit.Otherwise you wont get good lighting results (bleeding all over).

i flatten map so it is done automatic, i dont have time to unwrap “perfectly” every asset. But when I convert it to mesh and then do same process again it was fine in UE… I really dont get it what is happening. Just now done same process with editable mesh instead poly and it works fine, guess it is problem with some sort of mesh types, also you need to convert it to mesh after unwrap (this is must, dont get it why). Going to do with other assets to see what will happen.

P.s. really dont get it, first get channel 2 then move to 1 then collapse all to poly or mesh, you need to have this process, if you first made channel 1 then 2 and dont collapse it wont work, although you done same job on different steps…

If in UE you double click on your mesh, and if you press the UV button in the menu, you can see your UV and next to it you can change channels. What do you have in there, do you have Channel 0 and Channel 1? or do you have more?

i know, i had only problem with exporting them without overlapping, everything is fine now, except these small chunks that i need to pelt different in unwrap :slight_smile:

By default UE4 will assume that your first UV channel is for texturing and the second is for lightmaps, if you use the same UV’s for both (a single UV channel) then you will need to make sure that is set in the static mesh settings.
Also, by default it will try to generate lightmap UV’s to a new channel, make sure that’s turned off if you have them set up already. Make sure you have the correct number of UV channels if you only have one, in 3ds Max there’s a modifier for clearing a UV channel. To save memory it’s good to remove a UV channel if you aren’t using it.

As for your UV’s though, you need to do those properly manually for best results, automatic methods will have issues by splitting the mesh more than necessary, those small bits would require a high resolution lightmap to get good results without bleeding, when the UV’s are done properly you can use a smaller lightmap.

yea I am new at UT so I learn at my mistakes, unwrap all assets is tedious job :slight_smile: