This is a template code for homework 3 and should compile and run
as-is without modification. You may need to edit the Makefile to get
it to compile on your system.  It has been tested on the Stanford Myth
machines.

The code uses OpenGL and the FLTK user interface library (version 1.3.0
recommended). See the documentation at http://www.fltk.org/.

To edit the interface, use the FLUID editor (binary name: fluid). To
add additional sliders, it is easiest to copy and paste the existing
sliders and edit them by double clicking them. You will probably want
to change the Label under the GUI tab, and the Name and Callback under
the C++ tab.

[Credit goes to Victor Liu for revising the assignment to use FLTK!]