   OpenGL lighting range
  I noticed that when using Direct3D, it gives you the option to choose the range of the light you are using (i.e. set the maximum distance it will shine), but OpenGL does not.  I was wondering how do you determine the range of a given light with OpenGL?  I tried using google to find information on this, but never found anything.  Any ideas?  Thanks.   
  I think you are looking for light attenuation, note this is not applicable to directional light sources. This page provides a nice introduction:http://jerome.jouvie.free.fr/OpenGl/Lessons/Lesson6.phpHTH   