Maya Tiling Texture Light Maps

kimchee519

Just had a quick question on light maps for tiling textures. My question is do the light maps for the tiling textures get created the same way they would for are regular game asset? Since tiling texture usually expand outside the 0 to 1 space in the UV editor, I wasn't sure if my light map had to stay inside the 0 to 1 space like it would a normal asset light map. Thanks for any help on the subject

AdvisableRobin

For lightmaps, you need to have the UVs within the 0 to 1 space with no overlapping shells and decent amount of padding. Normally you create a second UV channel for the asset which has lightmap specific UVs.

For lightmap UVs you don't have to worry so much about UV distortion, so you can stitch more shells together to try and avoid seams which can sometimes give you artifacts.

kimchee519

Thanks for the reply AdvisableRobin. I was wondering if it is possible to have a static mesh that consists of three different materials when exporting out of Maya. Two of the three materials are tillable, but when I export the static mesh out of Maya into UE4 it is combined into one object and has three different material call outs. The problem is that when I look in at the UV light map channel in maya with the static mesh combined, has both the tillable texture and my one static mesh texture UVs all on top of one another, is that okay? Will my light maps still work normally in UE4? Sounds a little confusing, but basically just wondering if its possible to export a single combined mesh out of maya that consists of 2 different UV Sets and two different light maps, one tile able and one not and if it will still act normally and look okay in UE4 when I apply the different material call outs.

jfitch

I'm not sure with Unreal, you'd have to test it. I know with Unity that if you export one object in the same FBX that it uses the same lightmap UVs regardless of material.

If I were you I'd set the model up two ways--one with lightmaps respective to material, and one with a "global" lightmap with all of the objects combined into one. Then bake and see how it works!

kimchee519

Thanks, I tested it and got similar results, both looked okay, but the one with the combined light maps gave off a little different shadows. Anyone else know much about this?