Tiny Example OpenGL Shading Language programs
   Orion Sky Lawlor, olawlor@acm.org, 2005/2/11 (Public Domain)

Building:
  On a Linux machine with the GLUT libraries, you should be able
  to type "make" and get a "main" executable.  Anywhere else,
  you should be able to just compile "main.cpp" to get "main".
  
  On Windows, use
	cl.exe /EHsc /I. main.cpp /DWIN32=1 /DGLEW_STATIC=1

Running:
  The fragment shader is loaded from "fragment.txt" every frame,
  so if you change fragment.txt while the program is running, 
  it will immediately begin displaying the new version (as soon
  as the window is redrawn).