Why am I getting seams and shading on my modular wall section?

Development Rendering
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1

Hi,

Could anyone shed some light on what I’m doing wrong and causing portions of the lightmap to shade as pure black? I’ve checked other threads/questions on solving this issue and they pointed towards doing a second UV channel, which I’ve already done. I’m not concerned with the seam between the two meshes, but rather the drastic change to black on the second wall section. The points I kept in mind while creating it were:

  • Use a 128x128 texture to snap to (in preparation for 128 resolution light maps).
  • Give every face at least one pixel of UV space
  • Snap every vertex to a grid point
  • Keep at least 4 pixels between each UV island to prevent bleeding
  • Do not overlap any faces
  • Use as few UV islands as possible.
  • Where UV islands end, there should be natural seams in the model

Am I missing something? Thanks in advance.

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Alternate Image: https://i.imgur.com/u6cWo9e.png

2

Hi FinalDragon,

This answer for another user by one of our staff will explain how to set up in 3ds max your grid within the UVW Unwrap window so that you can fix this issue.

Setting up UVs for Modular pieces is key to getting a good lightmap without the shadows on the seams of your pieces.

I hope this helps you!

Thanks!

Tim

3

Hi Tim,

I went ahead and followed the instructions in that answer exactly, and it didn’t really change anything;

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I’d made some changes earlier that alleviated the issue of the wall turning completely black halway through, but the lighting still looks pretty bad on it.

Fortunately, I’ve also discovered that the issue is definitely not related to light maps. I went and tested what the mesh would build like in one of the example levels [SciFi Hallway] and the issue completely disappeared, and actually looks close to what my ideal lighting for the model would look like.

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I think I’m going to keep my old original UV channel for my lightmaps since it lights the bolts more correctly and making a new lightmap only caused more issues. Unfortunately, now I’m not sure what exactly is causing the issue in my level. Maybe some Light, World, or Lightmass settings?

4

Hi Final Dragon,

It could also be the way their scene is lit. you are using minimal lighting as well. You’re not using nearly as many lights that could be over powering the shadow of the seam. Have some lights that cast shadow and some that do not. Not every light in the scene needs to be a shadow casting light.

Try that and see if that helps at all. I’m curious to see what’s going on.

Thank you!

Tim