A tutorial about working with MaterialX and operators can be found here.

.mtlx files can be exported using Export Selected Shaders.

Enable

Selection

MaterialX

Mtlx Filename

Look

Assign Materials

Assign Properties

Assign Visibilities

Inputs

The MaterialX operator can be used to assign per-object shaders, geometry properties, and visibility settings.

Note that changing the subdivision type requires a full update.

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