To:	cwhizard AT sockets DOT net
Cc:	edkiser AT jaxnet DOT com, djgpp AT delorie DOT com
Subject:	Re: Question about Doom.
Message-ID:	<19970326.160817.7063.0.fwec@juno.com>
References:	<199703250435 DOT WAA28704 AT mail DOT sockets DOT net>
From:	fwec AT juno DOT com (Mark T Logan)
Date:	Wed, 26 Mar 1997 16:11:50 EST

On Mon, 24 Mar 1997 22:04:20 -0600 "Anthony Q. Bachler, BAS"
<cwhizard AT sockets DOT net> writes:

>(Ray Tracing == Ray Casting) = True.  Just a different way of saying 
>the
>same thing.  I use the term casting because it makes me think of 
>fishing
>and the code is fishing for a structure.  Sounds stupid, but hey, we 
>all
>need our little crutches.

  No they are not the same.  

  Ray tracing is used in things like POV-ray
and polyray, which are shareware renderers that produce extremely high
quality computer graphics.  Ever seen Babylon 5?  Ray casters are what
is used in wolf 3d and rott.  
  The fundamental difference is that raytracers send out one ray per
pixel, 
and trace the ray as it bounces off of objects and eventually hits a
light source 
or goes off into space.  A ray caster is a simplified version of this,
and it sends 
out one ray per column of pixels on the screen to draw the walls, and
then one 
ray per row for the floor and ceiling pixels.  Of course, the floor and
ceiling are 
often drawn using other methods, but this is what usually happens.

But remember, I'm not Sedgewick or Knuth or Foley or VanDam, so any or
all
of the above may be totally wrong.  I am pretty sure of it, though.


||                Fwec AT juno DOT com
||  "If ya don take your meat, ya can't have any pudding!!!!
||    How can ya have any pudding if ya don take your meat?"
||   -Pink Floyd
||

P.S.  Maybe there is some greater force at work here that I don't
understand,
         but seems to me your MIME things at the end are just annoying.

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