Object Properties
A Volume object or set is always linked to an external .vdb file. This can initially be non-existent if the Volume was created outside of Cinema 4D (e.g., using a Volume Builder that was made editable). When the scene is saved, a still non-existent *.vdb file will be created and saved with the scene file in a folder named vol. This relative path will be set automatically.
The file path can be changed at any time to create a new link. You can create a new relative path by simply entering a new file name (which will be saved/ found in a vol folder where the scene is saved). You can define an absolute path by clicking on the button at the right of the path and selecting the new path.
If you create new Volume objects in the scene that do not yet exist externally, these can be saved by clicking on this button.
Since Volumes saved in external files can be modified, clicking on this button will update the Volumes in your scene.
Here, the Volume object type of the externally linked *.vdb files will be shown first. Cinema 4D can only evaluate Float Comma SDF and Float Comma Fog. All other Volume object types will be partially imported but not evaluated.
Below, the number of Voxels and required memory are displayed.