Lighting bugs after lightning build

Development Rendering
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1

Before I built the lights, lightning was like this:

111874-screenshot_1.png
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But after I bulit it, something strange occurred, without any error:

111878-screenshot_2.png
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The model is quite complex. I tried different ways to unwrap the UVs and the only solution I found was to join all the objects into one and to generate the UV in Cinema 4D (it took me a lot of hours to do so):

111879-screenshot_3.png
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The result is this UV (UV 0 and UV 1 are equal and they are both correctly unwrapped):

https://s16.postimg.org/s7lsyvdh1/Screenshot_4.png

I already tried to put the Light Map resolution up to 512. (Sall I try something more?)
How can I fix this? I hope someone has the answer :slight_smile:

P.S: Also, Is there a better way to do the UV unwrapping without joining all the objects into one? (I can’t edit the model by doing so). If you know some good softwares, please let me know.

2

That is an extremely complex model to squeeze onto one UV. The way I’d tackle this is to break it up. You’ll find by doing so it’ll be easier to generate light maps as you’ll be doing them for each section rather than the entire model as a whole.

The UVs currently have no room to breath - in order to generate better lightmaps with less errors you need at least 2px spacing between each island.

Try breaking up the model first - UV mapping a section then importing to see if you are getting the same errors on a smaller bit.

Let me know how you get on.

3

Thanks for trying to help me! I tried to UV map a single section and it worked as expected, like you said
The problem is that the model is so huge I can’t group it in pieces manually so I’m actually trying to let C4D UV unwrap every single piece as separate object, insead of mapping the whole model into a single UV map.
Then I hope unreal will generate the light map from the UV correctly…
I’ll let you know the result :slight_smile: Thanks for the help anyway.

4

Great glad to hear it helped! Here is an awesome video series I watched that helped me, especially with light map resolution. http://www.worldofleveldesign.com/categories/udk/udk-lightmaps-01-basics-and-important-principles-for-creating-using-lightmaps.php

It’s udk but the principles are still the same.

I forgot to mention you don’t have to break up the model physically - you can simply add solid colours (or textures) to parts you want separate - uv map those parts and copy and paste them into separate uv spaces.

For example:

Make the spires orange - name the orange texture spires - find the uvs you’ve already done (if you have) or make new ones - then copy and paste the uvs into a new/seperate space.

Repeat.

That way you keep the model together but the uvs separate and in relation to what texture you’re going to apply to them in Unreal. You’re essentially colour coding parts.

5

If you found this at all helpful could you mark my answer up :slight_smile: