Compound

Function

Compound combines a number of independent shapes into a single entity.  No Compound mode exists in Selection Filter, and it cannot become an object for meshing.  A compound is merely a set of shapes.

Call

Geometry > Compound

<Compound>

Select Shape(s) to Compound

Select shapes to be combined into a compound.

Notes

In the case of Divide Solid, where solids are combined in a Compound, dividing a solid also divides the faces of adjacent solids along the divided solid.  This ensures the connectivity of elements.  While Divide Solid, etc. can be operated on one object at a time, if a number of solids are combined in a compound, Divide Solid, etc. can be operated on multiple solids.  

A compound is created when a shape is completely separated into two shapes through modifying operations.  For example, when the four faces of a box is removed by the Remove Sub-Face menu, the shape then contains only the top and bottom faces completely separated.  The two faces remain as a compound.

A Compound is also created in the process of making shapes, which can not be connected, into a single shape.  For example, if a Boolean Fuse operation is carried out on two completely separated solids, they remain as a compound.

As such if compounds are created in the process of modeling, it is necessary to execute Explode to identify the problematic shapes, which can not be connected.