Do these help?:
PickedU()/PickedV()
http://www.blitzbasic.com/codearcs/codearcs.php?code=515
PickedQuad()
http://www.blitzbasic.com/codearcs/codearcs.php?code=1603
PickedU()/PickedV()
http://www.blitzbasic.com/codearcs/codearcs.php?code=515
PickedQuad()
http://www.blitzbasic.com/codearcs/codearcs.php?code=1603