Unexpected triangulation of curves in USD file in Nvidia Omniverse

Omniverse General Discussion
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When importing a USD file into Nvidia Omniverse, I encountered an issue where the software automatically fills in faces between the curves, as highlighted in the red-circled area in the attached image. This seems to be due to a recalculation of the vertex order, which is not intended.

This problem does not occur when viewing the same USD file in other applications, where the curve displays correctly without any additional triangulation or automatic surface creation.

Expected Result: The curves should be displayed cleanly without any automatic triangulation or surface filling, as seen in other software.

Actual Result: The curves are being connected, creating unwanted geometry between the vertices.

System Information:

  • Version of Nvidia Omniverse used: Issac Sim 4.0.0 / USD Composer 2023.2.5
  • Operating System: Windows 11
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How are you generating the usd file ? Are you exporting from your CAD software as a usd file or are you using our built in CAD importer to read a cad file ? I have not heard of this problem before. Why is your mess so DENSE ? That wireframe looks like a simple wall element, yet it is completely white with wireframe geometry. I think you need to consider optimizing your mesh and the curve elements will resolve better.

We use a standard NURBS HOOP importer. If it detects bad vertex or open vertex it has to close that open loop. I would investigate your workflow further up the chain.