Lightmap issue

Hello guys. This is my first post and i am new in UN4.
I have a big model and i setuped a second UV map for lightmap and i set the light map coordinate index to 1, but no matter what, i have a very damaged lightmap. Any idea?
Thanks in advance

Hey there,

Try to let unreal to auto generate the lightmap. Go to your 3d program, remove the lightmap channel and export to Unreal. After that, open the mesh and check if the unreal have inserted second uv channel, then insert the mesh into level, build lights and check if any change has made (visualy)

Important: Before exclude the 2nd channel in your 3d program, save all work to a differente name to avoid problems.

After al this, give us a new screenshot to let us determine if the problem is in the 3d Model UVS or not

Lightmap res works like this:

I you have a texture lightmap with 2k, it´s better to set the lightmap res to 2k

If u have 4k lightmap texture, set the lightmap to 4k res, and so on…

And yes, that´s the better way to fix lightmap issues

Thanks. Unreal auto uv did not solve the problem. but i fixed it by increasing the lightmap res. I am not sure if its a best option or not, but it works.

Melechesc, this tutorial is very usefull:

Unreal Lightmap

I hope that helps.

Best regards,