opengl and gravity

I would like to know how to apply SIMPLE gravity to opengl.I know it depends on game but as i understand i have to modify camera or something?Some vectors?How do i calculate it.I also want to be able to apply gravity to objects all around.Thanks for help

nehe.gamedev.net just posted a new tutor on how to do simple object psyhics like gravity.

Originally posted by Fikus:
I would like to know how to apply SIMPLE gravity to opengl.I know it depends on game but as i understand i have to modify camera or something?Some vectors?How do i calculate it.I also want to be able to apply gravity to objects all around.Thanks for help