Universal Scene Description (USD) File Format Support

Alias 2025 introduces USD (Universal Scene Description) as an additional file import and export format. Use the USD format to improve your data interoperability and make your collaborative work easier.

USD was developed by Pixar to facilitate collaboration and enable the exchange of various types of data. Along with the base .usd format (ASCII or binary based), Alias also supports the format variants, which include .usda (ASCII based), .usdc (binary based), and .usdz (uncompressed zip archive file).

On export, NURBS and subdivision geometry are automatically converted to mesh data, using the same tessellator as Alias Hardware Shade. USD also provides the following:

Object names and hierarchy are preserved (See Prepare .wire files for USD export below).
Import and export of perspective and orthographic cameras.
Import of all common types of lights, such as ambient, spot, area, directional, and point lights. Dome and disk lights cannot be imported.
When importing USD, shaders and materials are set to the Diffuse Color setting. Shader names are preserved, which means you can use the Replace Shader by Name option to reassign these shaders from your specified shader library.

Note: To avoid name clashes when exporting content to .usd, .usda or .usdc, it's important to name the output of each variant differently. Otherwise, your content may get overwritten. For example, if you export wheel.wire to wheel.usd, a directory called assets-wheel is created, which contains the .usd output of the .wire file. If you then export the same wheel.wire file to wheel.usda, the same assets-wheel folder created by the first .usd export is used, overwriting the .usd files with .usda files.

In this case, naming the output directory for the .usda export as assets-wheel-a avoids the name clash.

Preparing .wire files for USD export

Before exporting your .wire files to USD, consider the following:

Shading and Textures

Objects with textures only display the current Diffuse Color in USD. To better approximate the color of original texture, set the Diffuse Color to the prevalent color in the assigned texture.
For objects shaded with metal type materials, transfer the Specular Color value of the material to the Diffuse Color. This will provide a better color match for the metal material in USD.

Object hierarchy

Recreate your layer hierarchy using groups instead of layers and layer folders. While doing this, be aware that some grouped objects in Alias may belong to two separate layers.

For more information see the following: