As a beinner to UE4 (moving from unity mainly for archviz) I have a few questions regarding content creation and creating a 2nd channel for lightmap creation.
is it a must to have at-least 1 uvw map created before I import things
If I’m to create an object on and plan to apply materials inside UE4, do I need to unwrap it in 3ds ? (even am not going to apply any material in )
Does glass objects need a lightmap uvw channel too?
do I need to tick create uvw for glass objects like windows etc?
Thanks in advance
P.S
I used 3ds vray and unity to create interactive 3D archviz projetcs, but noticing the quality I could achieve with unreal engine, I decided to try out and I think I will be sticking to it!
You will have at least 1 UV when you create anything in or any modeling program to begin with. This is your texture UV.
Any object that is intended to use static or stationary lighting will need a second UV channel for your lightmap. This 2nd UV channel needs to make sure that you have no overlapping faces.
All unwrapping needs to be done in whatever UV tools or modeling software you choose to use. UE4 does not do UV Unwraps. If you use the “Generate UVs” option in UE4 for lightmap generation it is only repacking the texture UV so that there is no overlapping faces. It does not break UV shells or cut seams so it’s important that if you use this option you make sure you have set up your Texture UV properly as well. (Ie. think of a cylinder that has been projection mapped rather than cutting and edge seam for the side and flattening that out to a rectangle. This will still generate a UV Overlap error in UE4 because the 2nd channel generation for lightmaps will only repack and not break the UV shell.
Feel free to ask any questions as I use 3Ds and a lot of work with Lighting and Lightmapping.
