What is EGS_Windows? Where can I find it?

[ftessier]

A number of users are asking about the EGS_Windows software, where they can obtain a copy, and whether it will eventually be distributed as part of EGSnrc again.

[ftessier]

What is EGS_Windows?

EGS_Windows is a Linux GUI interface for interactive 3D visualization of BEAMnrc geometries and simulated particle tracks. It was developed at NRC during the 1990s. The latest major version 4.0 was released by Joanne Treurniet and Dave Rogers in 1999.

EGS_Windows has not been developed actively for over 20 years. The last patch release was version 4.0.2, in January 2002. Today, many EGSnrc users (developers included) rely on the egs_view gui to visualize egs++ geometries and simulated particle tracks. However, egs_view does not handle BEAMnrc-generated geometries and tracks.

EGS_Windows is not a version of EGSnrc for the Microsoft Windows OS! The EGSnrc software does run on Windows, but this is unrelated to this GUI. Incidentally—and ironically—the EGS_Windows software does not run on the Windows OS.

Where can I get EGS_Windows?

You can download the standalone Linux executable EGS_Windows_4.0.exe from the Release 2021 page. Also, notably, Mohammad Bakhtiari implemented a Matlab version of EGS_Windows, which runs on any OS running Matlab.

EGS_Windows fails to launch, what can I do?

The standalone executable is linked against legacy versions of the Linux X11 libraries. Typically, this implies that EGS_Windows will fail to launch with an error message of this kind:

EGS_Windows_4.0.exe: error while loading shared libraries: libXmu.so.6: cannot open shared object file: No such file or directory

This can be resolved by installing the libXmu.so.6 library (or other missing libraries, according to the message). How to resolve this depends on your specific Linux installation. For example, on a CentOS 7.9 installation the command yum install libXmu.so.6 resolves the problem. Note that the executable does not work on macOS (the executable format is not recognized).

For the record, here are the dependencies for this executable, from ldd EGS_Windows_4.0.exe:

linux-gate.so.1 => 
libXmu.so.6 => /lib/libXmu.so.6
libXext.so.6 => /lib/libXext.so.6
libX11.so.6 => /lib/libX11.so.6
libm.so.6 => /lib/libm.so.6
libc.so.6 => /lib/libc.so.6
libXt.so.6 => /lib/libXt.so.6
libxcb.so.1 => /lib/libxcb.so.1
libdl.so.2 => /lib/libdl.so.2
/lib/ld-linux.so.2
libSM.so.6 => /lib/libSM.so.6
libICE.so.6 => /lib/libICE.so.6
libXau.so.6 => /lib/libXau.so.6
libuuid.so.1 => /lib/libuuid.so.1

What are .egsgeom and .egsgph files?

These are the two files that EGS_Windows needs to render the geometry and the tracks. You can generate them by running a BEAMnrc simulation with the IWATCH option set to For EGS_Windows. Then you can launch the viewer from the the command line, with the two filenames as command arguments.

Can I get the EGS_Windows source code?

Yes, soon! We plan to add the original EGS_Windows source code to the EGSnrc repository, so that anyone can compile it, or even continue developing it if they wish!