How to make UV maps work in Isaac Sim?

[JeanLesur]

Isaac Sim Version

5.0.0

Operating System

Ubuntu 22.04

GPU Information

• Model: RTX 4080 Laptop (80W)
• Driver Version: 575.64.03

Topic Description

Detailed Description

I need to apply UV maps on some assets but the UV maps created with Blender are not working in Isaac Sim (despite working fine with other software).
I have the impression that the UV map is simply pasted on all faces of the mesh and this shouldn’t be!

So I am wondering how to correctly setup Isaac Sim for the UV map to work.

Steps to Reproduce

1. In Isaac Sim, create a simple mesh (e.g cube) and export it to .obj file
2. Import the .obj in blender.
3. In Blender, go to “UV Editing” menu and UV > Export UV Layout to save it to .png file
4. Modify the layout with tools like inkscape/GIMP/etc and save it
5. Apply the UV map in Blender and see that it works correctly
6. In Isaac Sim, right click the mesh and create a new material. In the property tab, under albedo section, choose the .png image created earlier as the albedo map. Observe it is not working

See screenshots below.

Error Messages

NA

Screenshots or Videos

In blender, create simple mesh and get the UV map layout:

Open this UV map layout with an image editing software and modify it:

Apply it in blender, see the nice result:

Apply this map in Isaac Sim and see that it is not working

Additional Information

What I’ve Tried

Tried several different UV maps, all of them not working. I tried to tweak the parameters of the UV map in the property panel but without success.

Related Issues

UV-Maps from Blender not carried over

Hi, I’m trying to export this simple scene from Blender: [scene in blender] exported like this: [usd export] Comes out in create like this: [scene_in_create] Obviously, the UVs seem to be set to the default and my object specific maps are not respected. I’m using Windows 11, Create 2022.3.3-RC14, Blender 3.6.0 Alpha. Help is much appreciated.

[Simplychenable]

@JeanLesur just out of curiosity, did you ever export the UV unwrapped cube from Blender back into Isaac Sim? looking over the step by step in your post, you unwrapped it in Blender, which works as expected but i didn’t see a step (between 5 and 6) in which the mesh got brought back into Isaac Sim as a USD file. despite having a texture that works with only the mesh in Blender, the cube in Issac Sim will remain as the original/not UV’d cube and will not work with the custom texture.

in other words, try exporting the cube (with or without the texture applied) from Blender as USD or FBX so the UV gets baked into the mesh before applying the texture in Isaac Sim.

[JeanLesur]

thanks for the quick answer
And you are right, i had to export the mesh from blender as .usdc to make it work! Sorry for that :)

marking as resolved