Hi there,
Unreal needs special uvs on uv2 for lightmaps.
Idealy they should look rectangular and not diagonal.
They should also be quantised to pixel resolution.

Tips? I cant get this to work with the Houdini tools in H16.

kind regards

Olaf

Hi Olaf,

Im switching my current project from realtime to baked lighting and had the same problem today….

You can use layers to create several uv sets.

https://www.youtube.com/watch?v=U90eHb8OLr4 [youtube.com]

You can also create a hda with several layers and they should show up as different uv sets in unreall

Best regards,
Johannes

Hi Johannes,
i figured it out by now.
this is very usefull
https://www.orbolt.com/asset/mifth::mifth_uv_grid [orbolt.com]

I also made a little tool to make sure the uvs are pixel perfect.

thanks

Olaf

Instead of using the Layer SOP, you can use copy attribute to copy uv attribute of your lightmap-unwrapped geo, to uv2 of your target. The result will be the same as if you were to use the Layout SOP. It's just a different way of achieving the goal.

What are the requirements to get the UV's to work properly. Evertime I export as a HDA the same asset refuses the work properly. But if I simply export as FBX it works! I'm baffeled.

Noboru_Garcia
What are the requirements to get the UV's to work properly. Evertime I export as a HDA the same asset refuses the work properly. But if I simply export as FBX it works! I'm baffeled.

Here's a video I made on the topic. Might help someone!

https://youtu.be/ZGMrwwKglKE [youtu.be]