I started a 3D model viewer years ago and used this basic technique to render the grid:
http://www.blitzbasic.com/codearcs/codearcs.php?code=839
I also developed this technique for vertex 'handles':
http://www.blitzbasic.com/codearcs/codearcs.php?code=1008
http://www.blitzbasic.com/codearcs/codearcs.php?code=839
I also developed this technique for vertex 'handles':
http://www.blitzbasic.com/codearcs/codearcs.php?code=1008