3D & Animation Creating lightmaps in 3ds Max

[Catalavos]

I've been spending a lot of time creating static mesh replacements for some of the buildings in my map and now that I have UVW unwrapping figured out I also have some buildings that actually look like something. I'm stuck now, however, on lightmapping. I've spent the better part of 3 days looking for tutorials and haven't found one that really helps me understand how to correct 2 problems: how to fix inverted faces and overlapping faces.

So... how do you guys do it?

 

[Twrecks]

I use 3dsMax.

In the UV mapping dialog you can select inverted faces and flip them. Padding will seperate the clusters to prevent overlapping.

Hourences has a good tute:
[url]http://www.hourences.com/tutorials-ue3-lightmapping[/URL]

The UDN gets into the technical aspects:
[url]http://udn.epicgames.com/Three/LightMapUnwrapping.html[/URL]

Heres another from waylon-art with Maya:
[url]http://waylon-art.com/LearningUnreal/UE3-10-LightMaps.htm[/URL]

 

[Spaehling]

hehe Twrecks its seems that you helping everbody out with his light-issues^^

 

[Catalavos]

TWrecks,
Thanks for the tutorials!
What I'm still stuck on, however, is how to actually select and fix the individual overlapping faces on the model. Is this done after you've created a second set of UVW's or do you fix them on the model before applying any UVW Unwrap modifiers?

What I've been doing is: create the model, apply UVW Unwrap modifier with "flatten" mapping, re-arrange the individual faces so that the materials display properly when rendered, then create a second UVW channel for the lightmap. But at this point I get stuck on how to actually manipulate the individual overlapped faces in order to fix them.

 

[Twrecks]

Cat-

Lemme explain it for you.

Step 1. You make the mesh, for this example it will be a square crate.

Step 2. UV map the crate, 6 sides each with 2 triangles (polys). You can "share" UV space here because maybe all the sides are the same, and so is the top and bottom. The UV map is assigned to channel 1 (diffuse).

Step 3. Make a texture from your diffuse UV map, this is what players see, assign it to UV channel 1 and your crate looks like a crate

Step 4. Make a "Lightmap", this is a second UV map on channel 2, no overlapping faces, no inverse faces, take up as much room in your coordiate grid as possible without going outside, and "pad" between the faces (sides of crate) so shadows don't bleed from one face to another. In this case all 12 polys are laid out, 6 nice boxes each with two polys spaced nicely, no texture.

Step 5. Import mesh and diffuse texture into the SDK. If done correctly, your crate will have the texture on UV channel 0, and the lightmap on channel 1. (SDK channels are minus one from your mesh making software).

Note: If you didn't import your mesh with a lightmap (UV#2 map), you can take your mesh and UV map it again, then import it as a ASE file to pull the UV lighmap into the Mesh editor inside the SDK.

 

[c200k]

I also use "flatten" mapping as initial step for creating a lightmap, after that I re-arrange and scale the faces. Overall, I don't like creating lightmaps

This is also very helpful:

http://www.worldofleveldesign.com/c...t-principles-for-creating-using-lightmaps.php

Regards