SOLIDWORKS models are commonly divided into faces, edges, and vertices.
These entities become references for child features. For example, you can add a fillet
on the edge formed by the intersection of two faces.
A graphics body does not have any of these references because it consists
of only mesh facets. Very few features can reference the mesh facets of a graphics body.
When you convert a graphics body to a mesh BREP body, the mesh BREP body consists of a
single face, which is of limited value.
In this example, the graphics body was originally a cube in another CAD
program. You exported it to
STL, then imported it
to SOLIDWORKS. The graphics body consists of 12 facets (two facets per what were
originally square faces.)
If you convert the graphics body to mesh BREP, the 12 facets remain, but
the entire cube would be a single face.
To return the cube to 6 faces, 12 edges, and 8 vertices, you need to
segment the single-face mesh BREP cube to group facets into what you consider faces.
Once segmented, you can add child features to the mesh BREP body, such as fillets and
chamfers that reference faces and edges.
Standard SOLIDWORKS BREP bodies converted to mesh BREP maintain their
segmenting and do not need further segmenting.