Only the volume object is exposed in the user interface. It is based on OpenVDB internally. Drawing and rendering code will follow in another commit. https://wiki.blender.org/wiki/Source/Objects/Volume https://wiki.blender.org/wiki/Reference/Release_Notes/2.83/Volumes Hair and PointCloud object types are hidden behind a WITH_NEW_OBJECT_TYPES build option. These are unfinished, and included only to make it easier to cooperate on development in the future and avoid tricky merges. https://wiki.blender.org/wiki/Source/Objects/New_Object_Types Ref T73201, T68981 Differential Revision: https://developer.blender.org/D6945