Troubleshooting: Log more info in PlyReader.cpp
Troubleshooting: Log more info in PlyReader.cpp

If the filename does not exist or is an invalid ply file, a WARNING is logged giving the faulty filename.
But if someone request an information from the file and this file does not exist or is invalid, then an ASSERT raises a FAILURE giving the faulty filename.

simquest/opensurgsim,simquest/opensurgsim,simquest/opensurgsim,simquest/opensurgsim