Mesa/OpenGL:

for the visualisation in three dimensions engine is required. Mesa is a free one and can be downloaded easily, together with a demos package [3]. The instalation is done as follow

1. Go to the top directory of Mesa and execute the command

   make linux-x86
   

   (or the name of the system configuration)
2. Update the library environnement variable with the Mesa/lib directory

   export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/user/Mesa/lib
   

3. The demos are installed in the Mesa/progs/demos directory, and one can run one of them to test if Mesa is well installed.