Tools to extract one mesh's textures from an atlas?

Unity Engine
1

There are a few mesh assets I’d like to use that use small portions of large atlas textures (say, a 128x256 chunk of a 2048x2048 map). I’d like to trim the portions they use from the atlas in the cases where I don’t need anything else on the atlas in my project. Unfortunately, sometimes the pieces these meshes use are all over the atlas, and I don’t have the art tool skills to make new textures manually and remap the meshes. I’ve been looking for tools to extract the portions of the atlas UV mapped onto the mesh and build a new texture out of them, but everything I can find for texture extraction / remapping / baking seems to be based on MAKING atlasses, not un-making them, and is mostly for 2d sprite packing work.

Simplygon seems to do this as part of their mesh reduction tool, but: A) you can’t get the texture extracted without the mesh reduction (as far as I can tell) and B) texture remapping actually isn’t working for me at all in 5.4 (the material shows up as blank white).

Any other options I’m missing? Thank you!

2

With 3D Coat it is very easy to create a Texturealtlas or extract from a Texturealtlas without loss the Texture.

You import your mesh in the Paintroom (pixelbased)
go to the UV Room
create a New UV set

select the cluster from old set, and choose menue “move select” that put the selected cluster to the new set.
You can scale rotate or move the clusters , than press apply UV set . A new UV map is extracted with the texture.
That works same in the another direction to create a Atlas.

2 Likes
3

Thank you for the recommendation, I will check that out!