The Birth Objects operator allows you to convert scene objects into particles.
Object list: the list of input objects which will be converted into particles.
Inherit object geometry: controls whether the meshes of input objects will be assigned to corresponding particles.
When “inherit object geometry” is disabled, only object transforms will be transferred to birthed particles. This can provide a significant speedup if the input objects have high resolution meshes, but you do not need those meshes to be assigned to the new particles (for example, if you want to align particles to objects but don’t need those particles to inherit the meshes).
Group members: if an input object is a group head, enabling this setting will convert its constituent members into particles.
Object elements: if an input object mesh has multiple sub-elements, enabling this setting will split them into multiple particles.
Center all pivots: centers the pivots of extracted meshes.
Update Cache: click this to manually update the internal cache which holds mesh data for all input objects.
Auto update: controls whether changes to input objects will automatically update the operator’s internal mesh cache.