- The demos are best seen in order, from the most basic, to the advanced.
- Run the "rundemo" script.
- Note that most of the demo's were written using cut & paste, starting
- with the simplest demo, cylinder.c. We could have written a fancy demo
- package that avoided all of the cut&paste of code, but we felt that this
- would only hide what we are trying to show here: the programming API for
- the tube & extrusion library.