Adding custom Line Types

I am looking for instructions to upload a file with custom line types.  is this possible?  If so, is the formatting of the file the same as other CAD programs?

The current code base doesn't allow user defined line types:

https://github.com/LibreCAD/LibreCAD/blob/master/librecad/src/lib/gui/rs_linetypepattern.cpp

If needed, we can design a way to allow customized line types.