USD

A procedural node that is capable of reading USD files.

Path

The path to the USD file.

Object Path

Determines which USD primitive(s) are rendered. When empty (default), it will render the whole USD file.

Frame

The frame number to expand in the procedural.

Clear Controller

By default, the frame parameter is linked against the animation timeline frame. This button unlocks that link.

Namespace 

This custom namespace can be used instead of the procedural name, to reference contents through absolute or relative paths.

Debug

Dumps verbose logs about the USD nodes being created.

Up Axis:

The Up Axis for the procedural. Z is the default.

Select Operator

Gives the ability to connect Procedural/Alembic nodes in the Operator Graph Editor.

From the Operator Graph Editor, you can list the objects connected to the operator.

 

In this case, there are three INodes, two of them being 3ds MAX instances of the same Arnold Alembic object.

Viewport

Procedural/Alembic files can be introspected to retrieve geometry and display it in the viewport.

Display Mode

The available viewport display modes are:

• Bounding Box (Fast): Displays the contents as a bounding box. It does not need the full ass file load, it simply looks for "bounds" being present. If it is not, it keeps the previous behavior.
• Bounding Box (Content List): Displays the contents as a bounding box and in the content list.
• Points: Displays the contents as points.
• Wireframe: Displays the contents as a wireframe.
• Shape: Displays as a shape with full shading.

Bounding Box Threshold (ratio of screen size)

Defines how much to extend the bounding box of the object. The default value is 0.02.

Animation Cache Size (in frames)

Animation frames load on demand and are kept in a cache of the size defined in the UI. If the cache is not used, the data is always trashed (same as the cache size is 1).

Content

Shows the contents of the file. The content tree view selection cannot be used for selection. Double-clicking copies the sub-node name (path) and can be pasted in an operator.