minimal test case to check merged surface

[shimwell]

When two surfaces are the same in the geometry then the brep file allows them to be merged into one surface.

This method currently loops through each volume and gets the surfaces for the volume, the surface are then saved as an stl file and imported again to make the h5m file

This leads to the same surface being defined twice in the geometry.

The touching surface would appear in two stl files and then it would appear in two meshes when making the pymoab mesh object

the touching surface is not overlapping but is in the same location as another surface and therefore can result in problems during particle transport.

Perhaps a minimal test case can be set up that makes this geometry and checks the conversion results in 2 volumes each with 3 regular surfaces and 1 shared surface

one volume is drawn in black lines while the other volume is drawn in red lines

.

[shimwell]

perhaps this issue should live in the vertices to h5m package