Re: 3-D Programming
[Prev][Next][Index][Thread]
Re: 3-D Programming
James Hall <jrhall@INFOCOM.COM> muttered:
<In a relevant comment I have heard, Right from the source!, that Id
<Software is releaseing the source code to Doom... Several plans in
<progress by indivials include an opengl version of doom and a
<client-server based version of doom (to allow built in internet play)
<to learn more about this finger Johnc@idsoftware.com (finger clients
<can be obtained from www.shareware.com)
Actually fingering can be done by accessing the url:
gopher://idsoftware.com:79/0johnc
This method (gopher://hostname:79/0name) will work in most browsers.
(Some versions of Netscape don't like it.)
Neil Padgett
<> Date: Thu, 21 Aug 1997 20:33:31 -0400
<> Reply-to: "Thomas J. Hruska" <thruska@TIR.COM>
<> From: "Thomas J. Hruska" <thruska@TIR.COM>
<> Subject: 3-D Programming
<> To: CALC-TI@LISTS.PPP.TI.COM
<
<> Okay all you people who keep asking about 3-D games. I am going to
release
<> some highly secretive info. that only advanced programmers know
about (and
<> who subscribe to several Game Development magazines or spent $250
on game
<> programming books). Here is the low-down on how a 3-D engine
works:
<> "slivers" and ray tracing
<>
<> I will be using the game Wolfenstein 3D for my discussion (DooM
works in a
<> totally different way but has the same 3-D principles).
<>
<> Ray Tracing is just a process of taking a central point (the user's
current
<> location) and "drawing" a line till it hits a wall/object on a 2-D
map
<> (DooM uses a Binary Tree format for its levels...not a 2-D map).
If you
<> span multiple lines so that they cover an area of 60 degrees (Field
Of
<> Vision or FOV), you can produce a realistic 3-D image. If you use
sines
<> and cosines for the line, you will need to account for the fact
that you
<> are super-imposing polar coordinates onto rectangular coordinates.
Without
<> counteracting this, you will end up looking through a fish's eye
view in
<> the 3-D world.
<>
<> "Sliver" is a technical term for drawing a scaled sprite. My
SpriteDraw
<> routine just needs a little editing and it will be ready for 3-D
games. A
<> "sliver" is just a single-pixel width sprite that has been scaled
according
<> to the Ray Tracer. All a 3-D game is made of is a bunch of little
slivers.
<>
<>
<> I hope that I have helped someone understand what a simple 3-D
engine is
<> made of. If you don't understand any of it, just e-mail me and
I'll be
<> happy to tell you. The source of this info. came in a book called
"Tricks
<> of the Game Programming Gurus." Dadelus (for the TI-85) was
written using
<> this and another book (can't remember the name).
<>
<>
<> Thomas J. Hruska -- thruska@tir.com
<> Shining Light Productions -- "Meeting the needs of fellow
programmers"
<> http://www.geocities.com/SiliconValley/Heights/8504
<> http://shinelight.home.ml.org
<>
<>
References: