Setting out light maps confusion - youtube video

[ellenfshelley]

Hi there,

I've currently been learning light maps for ue4 - I read that you need to set up your uv grid to match light map resolution. - leaving 2px gap between uvs. I saw in this video wes posted https://goo.gl/JMBnnl that the light map uv's didn't have much padding and the grid is default? As long as the uvs are cut correctly, as in faces separated depending on how light falls is this okay?

[Fabian F.]

Hey ellenfshelley,

you should leave padding in your lightmap UVs to avoid shadow bleeding, but you don't need to work with a pixel-perfect grid.
Maya, for instance, can layout the UVs itself and uses a user-set distance between the UVs.

If the object is important, though, or you just want to learn how to create lightmap UVs, you should keep going the 'manual' way by setting the grip correctly and straighten your UVs as good as you can.
A minimum of 2px padding is advisable.

Even if the tutorial is for UDK, you can perfectly switch to UE4 from it: Lightmap UV Tutorial

I hope that help you.


Best Regards

[ellenfshelley]

Thanks for the nice response . When you say layout - is this the 'layout Uv' option Maya has? Also when you say straighten uvs what is the protocol if you have a spherical uv? Do you simply leave padding around the outer edges of the sphere for example? Or do you use the 'straighten uv command' maya has?

Thanks
Ellen

[Fabian F.]

Hey ellenfshelley,

with 'layout' I simply mean laying those UVs out, like paper or so, not the Maya-specific command.
The same goes for 'straighten' the UVs.

Using this term I simply mean making as many straight and rectangle UVs as you can. Keep distortion and curvature/bending away, if you can.


Best Regards