This tutorial demonstrates how to open a USD scene from NVIDIA, modify its contents, and render it with Arnold. USD files can easily be opened and rendered with Arnold using a stand-in (procedural). We will use operators in the stand-in to adjust the USD lighting (from NVIDIA Omniverse). We will also modify the mirror object and couch material using operators. Finally, we will disable the Omniverse lighting and replace it with Arnold lights.
Download the Attic_NVIDIA.zip file here (login required).
- Unzip the file Attic_NVIDIA.zip into a folder structure like the following so that the .usd file loads properly
- Create a stand-in (procedural). Select the folder next to Path and choose the Attic_NVIDIA.usd file.
- You will notice that the orientation of the attic geometry is Z-up rather than Y-up. This is because the original scene file originates from Omniverse which is Z-up. Rotate the stand-in -90 degrees in X.
- Create a camera (rename it RenderCam) and position it so that it looks like the image below.
RenderCam view. Stand-in Viewport Draw Mode set to Polywire.
Add Arnold Lights
- Create a skydome light.
- Create a physical_sky and connect it to the color attribute of the skydome light. Ensure to change the orientation axis to Z-up.
- Create light portals and position them outside the windows of the attic. They will help reduce interior noise from the skydome light through the small windows.
- Once you are happy with the lighting, disable ignore_textures, and ignore_shaders under Render Settings -> Diagnostics -> Feature Overrides.
Attic scene rendered with Arnold lights
That is it. Why not try adjusting some of the materials of other objects in the scene or try different lighting setups using operators.