BRL-CAD has a geometry exporter and importer for the International Graphics Exchange Standard (IGES) file format. If you run our g-iges exporter on some geometry, then run iges-g on that same geometry to import it back to BRL-CAD format, the geometry will have permuted vertex lists. Particularly for geometry already in polygonal format, such as our NMG or BoT geometry, this conversion should result in identical geometry but presently does not.

This task involves investigating why this occurs, reporting (in detail) why it occurs, and if obvious, making a recommendation on how to fix the problem.

Code:

• src/conv/iges