Add documentation on building and running the simple simulation examples.

[brugger1]

We should add documentation to the getting data into visit section of the manual on how to build and run the examples in the simulation example directory. We don't have any libsim documentation in the user manual, but this would be a good start to supplement what is in the GettingDataIntoVisIt2.0.0.pdf.

Here is how to compile one of the examples against an installation of VisIt.

gcc -I. -I/usr/gapps/visit/3.1.4/linux-x86_64/libsim/V2/include -L/usr/gapps/visit/3.1.4/linux-x86_64/libsim/V2/lib -Wl,-rpath=/usr/gapps/visit/3.1.4/linux-x86_64/libsim/V2/lib -lsimV2dyn -ldl -lm sim4.c -o sim4

Here are the environment variables to set for running the simulation.

setenv LD_LIBRARY_PATH /usr/gapps/visit/3.1.4/linux-x86_64/lib/mesagl:/usr/gapps/visit/3.1.4/linux-x86_64/lib
setenv VISITPLUGINDIR /usr/gapps/visit/3.1.4/linux-x86_64/plugins

Note that sim4.c doesn't do much and sim1.c through sim12.c incrementally add functionality in terms of additional data to be passed to VisIt. Even sim12.c doesn't pass valid mesh and variable data though.

[brugger1]

The GettingDataIntoVisIt2.0.0.pdf is located at:

https://wci.llnl.gov/sites/wci/files/2020-08/GettingDataIntoVisIt2.0.0.pdf

[brugger1]

There is some information on building an example on a Mac at:

http://www.visitusers.org/index.php?title=VisIt-tutorial-in-situ

[brugger1]

The examples are located in src/tools/data/DataManualExamples/Simulations.

[markcmiller86]

Be aware of some of the issues mentioned in #16989 also.

[markcmiller86]

I think there are other aspects of this especially for macOS discussed in #16986 too.

[markcmiller86]

Sorry to dribble out but a number of imported email discussions mention the mandelbrot example. I dunno if they also shed light on any missing documentation too but they might.