Download

How to map UVs for lightmap on a wall MAYA

I am trying to make a light map for a wall.

I understand that you should put spacing between each face, and that the vertexes should be on the grid.

I tried to do an automatic mapping. The image will be attached.
The issue with that is

  1. Notice all of the little faces that are skinny and tall. They aren’t even a pixel wide, so how would I get them on the grid?
  2. That would take a very long time, and I don’t even know how I would do that for the triangle shapes.

Most tutorials I have seen use very simple boxes, which is obviously easy to just select each face and space them apart.
However, I am dealing with a more complicated wall. Not extremely complicated, but more than just a few faces.

How would I actually map out the faces?

I appreciate anyone’s help. This is very frustrating. I have been in a great development mood, making progress, and now this!

Thanks.

mb you post your mesh 1st?)

how how - grab tiny ones. scale them/sew them/remake UVs => bake. try again :smiley:

I’m not an expert by any stretch of the imagination, but if those small faces that you are worried about aren’t that visible, then you don’t have to necessarily maintain the aspect ratio of them. These UV’s are for shadows so its a bit of a judgment call to determine how much UV space those faces will actually require. Just as an experiment, see how it looks in game with those faces scaled up to a width of 1 pixel and a length of maybe 2-3 pixels. I would then hit match grid on them in the toolbar instead of doing it manually.

Also just another note. I’m not sure what lightmap resolution you are planning on using, but from the picture it doesn’t look like you have enough space between the faces to prevent shadow bleeding. I usually try to maintain 3 pixels between any face.

Good luck! Someone with more experience can probably chime in with more precise methods.

Refer to these tutorials: http://worldofleveldesign.com/categories/cat_udk.php#lightmapping

To ensure no shadow bleeding at all you have to match the resolution of your grid to the resolution of your lightmap.

This thread also has a good breakdown of grid size vs lightmap resolution: https://www.reddit.com/r/UE4Devs/comments/246whl/the_most_important_thing_about_lightmaps/