Path: chuka.playstation.co.uk!news
From: "Jon Prestidge (alias Moose)" <zmoose@premier.co.uk>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Normal Vector Directon
Date: 6 Feb 1999 13:26:37 GMT
Organization: PlayStation Net Yaroze (SCEE)
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Please help!
My paranoia is getting the better of me... I just can't be sure if my
normal vectors point the correct way.  They are perpendicular to the
polygons' faces OK and about 4096 long, but they could be 180degrees out
for all I know.  Everything I read about normals I can't seem to interpret
catagorically on this.... I may have a bug in my normal calculation or I
may have specified the points to it in the wrong order
(clockwise/anticlockwise).  Is it the same on all graphics archithectures
anyway? Everything looks OK in my game but that could be because I have my
lighting directional vectors the wrong way round too!  Doh!   What's the
correct way on the playstation then?

If you were facing a triangular polygon with the points defined in a
clockwise direction, would the normal be pointing away from you,  or
pointing towards you and poking in your eye?

Jon