Conversion from BREP to PLY is not supported yet :(

A Brep file is a 3D model stored in the boundary representation (also known as B-rep). The Brep format is a part of Open CASCADE Technology (OCCT).

The Brep structure is made up of two major components:

• topological components such as faces, vertices, and edges;
• links between components such as surfaces, points, and curves.

It comprises three-dimensional data such as vertices, edges, wires, faces, shells, solids, compounds, edge and face triangulations, polylines on triangulations, space location, and orientation.

PLY is a computer file format known as the Polygon File Format or the Stanford Triangle Format. It was designed to store three-dimensional data from 3D scanners. The data storage format supports a relatively simple description of a single object as a list of nominally flat polygons.