The Volume node is used to render volume files such as VDBs created in other 3D applications (Figure 1).  VDBs are a generic volume format for creating effects such as smoke, fog, vapor, and similar gaseous objects. VDBs can consist of a single frame, or an animated sequence. 3D software packages like Houdini generate and export VDBs. VDB files can be downloaded at http://www.openvdb.org/download/. This node is covered in more detail in the Volume Mediums topic under Effects.


Volume

Figure 1: Accessing the Volume node in the Node Graph Editor