USD/Alembic

A USD or an Alembic asset is a node that reads a USD or Alembic file and allows its content to be animated or sculpted like any assets in Rumba.

Importing a USD/Alembic asset

To import a USD or Alembic asset, Left Click on the File menu, then select Import USD/Alembic.

Note

By default, the USD files are shown. Change the extension to Alembic File to show Alembic assets.

Display options of a USD/Alembic asset

When importing a USD asset, by default its Subdivision is No Subdivision and its textures are not shown.

To change these settings and other display options, select the USD/Alembic asset, go to the Attributes widget and expand the Display Overrides tab.

../_images/usd_display_options.png
  • VisibilityThere are four modes of visibility available

    • Visible : The asset is always visible

    • Hidden : The asset is always hidden

    • Visible at Play : The asset is only visible when playing the animation

    • Hidden at Play : The asset is not visible when playing the animation

  • Picking : Whether the objects inside the assets can be selected or not

  • Subdivision LimitThe maximum level of Subdivision the asset can have. Its final Subdivision level is the lowest between this option and the viewport Subdivision level.

    • Inherit : The default Subdivision level, which is No Subdivision

    • No Subdivision : The asset without modification

    • Level 1 : The equivalent of Subdivision Low in the viewport

    • Level 2 : The equivalent of Subdivision Full in the viewport

  • TexturesWhether the textures are displayed or not on this asset

    • Inherit : The default texture display option, which is No Texture

    • Use Texture : Display textures on the asset

    • No Texture : Do not display textures on the asset

  • Render ModeThere are four render modes available

    • Inherit : The Render Mode of the viewport

    • Filled : Show the objects’ faces without the edges

    • Wireframe : Show only the edges of the objects

    • Filled with Wireframe : Show both the faces and edges of the objects

Animating a USD/Alembic asset

Objects inside a USD/Alembic asset can be individually moved and animated. In order to edit an object’s transform, it has to be added to an animation layer.

To do so, select the object and Left Click the + button of the Layer you want to add it to (if no Layer exist, create one beforehand, see Create Layers).

Note

When an object is editable, its transform appears in the Channel View widget and there are yellow or red bars in front of the values.

Sculpting a USD/Alembic asset

Objects inside a USD/Alembic asset can be individually sculpted.

To initiate sculpting on a USD object, select the object then Right Click on the usd_add_layer button in the Layers view and select Create Sculpt Deformer.

See also

For more information on sculpting, see the Sculpt Deformer Layer documentation.

Adding a Sticky to a USD/Alembic asset

It is possible to create a Sticky Deformer on objects inside a USD/Alembic asset.

To create the Sticky Deformer for a USD object, select the object then Right Click on the usd_add_layer button in the Layers view and select Create Sticky Deformer.

See also

For more information on sculpting, see the Sticky Deformer Layer documentation.

Exporting a USD/Alembic asset

To export a USD asset, Left Click on the File menu, then select Export to USD.

To export an Alembic asset, Left Click on the File menu, then select Export to Alembic….

See also

To export using code, see Export an alembic file and Export a USD file