<!-- MHonArc v2.4.4 -->
<!--X-Subject: Collision Detection -->
<!--X-From-R13: Qlaor eh Fnera <plaorNynhery.npgyno.hgrknf.rqh> -->
<!--X-Date: Tue, 19 Aug 1997 21:26:19 +0000 -->
<!--X-Message-Id: 199708192126.QAA12885#laurel,actlab.utexas.edu -->
<!--X-Content-Type: text/plain -->
<!--X-Head-End-->
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<html>
<head>
<title>MUD-Dev message, Collision Detection</title>
<!-- meta name="robots" content="noindex,nofollow" -->
<link rev="made" href="mailto:cynbe#laurel,actlab.utexas.edu">
</head>
<body background="/backgrounds/paperback.gif" bgcolor="#ffffff"
text="#000000" link="#0000FF" alink="#FF0000" vlink="#006000">
<font size="+4" color="#804040">
<strong><em>MUD-Dev<br>mailing list archive</em></strong>
</font>
<br>
[ <a href="../">Other Periods</a>
| <a href="../../">Other mailing lists</a>
| <a href="/search.php3">Search</a>
]
<br clear=all><hr>
<!--X-Body-Begin-->
<!--X-User-Header-->
<!--X-User-Header-End-->
<!--X-TopPNI-->
Date:
[ <a href="msg00677.html">Previous</a>
| <a href="msg00679.html">Next</a>
]
Thread:
[ <a href="msg00236.html">Previous</a>
| <a href="msg00221.html">Next</a>
]
Index:
[ <A HREF="author.html#00678">Author</A>
| <A HREF="#00678">Date</A>
| <A HREF="thread.html#00678">Thread</A>
]
<!--X-TopPNI-End-->
<!--X-MsgBody-->
<!--X-Subject-Header-Begin-->
<H1>Collision Detection</H1>
<HR>
<!--X-Subject-Header-End-->
<!--X-Head-of-Message-->
<UL>
<LI><em>To</em>: <A HREF="mailto:mud-dev#null,net">mud-dev#null,net</A></LI>
<LI><em>Subject</em>: Collision Detection</LI>
<LI><em>From</em>: Cynbe ru Taren <<A HREF="mailto:cynbe#laurel,actlab.utexas.edu">cynbe#laurel,actlab.utexas.edu</A>></LI>
<LI><em>Date</em>: Tue, 19 Aug 1997 16:26:17 -0500</LI>
</UL>
<!--X-Head-of-Message-End-->
<!--X-Head-Body-Sep-Begin-->
<HR>
<!--X-Head-Body-Sep-End-->
<!--X-Body-of-Message-->
<PRE>
Re the recent collision detection discussion: There was a pretty
good article on this in Computer Graphics and Applications about
3-5 years ago. The solution and conclusion there was that to do
realtime collision detection on complex worlds, you just have to
be really aggressive at eliminating needless work, using a whole
hierarchy of techniques, basically cheapest-first.
E.g.:
Typically much/most of the scenery is fixed wrt the ground: You
don't have to test motionless trees to see if they are hitting
each other. So don't. Similarly with parts of moving vehicles
&tc. They suggest that parts in contact are a nightmare for
collision detection algorithms anyhow, since they keep going in
and out of exact contact based on floating-point roundoff, and
fail all the cheap tests: Big win to set up your system to just
not do those checks.
Beyond that, just use a cascade of techniques cheapest-first as
aggressively and intelligently as you can: Sphere-intersection
checks and quadtrees &tc can rule out lots of potentential collisions
very quickly. Bounding-boxes aligned with the coordinate system
ditto. Potential collisions that pass those tests can be checked
on a simple convex hull, and potential collisions that pass -that-
can start checking against real device geometry.
</PRE>
<!--X-Body-of-Message-End-->
<!--X-MsgBody-End-->
<!--X-Follow-Ups-->
<HR>
<!--X-Follow-Ups-End-->
<!--X-References-->
<!--X-References-End-->
<!--X-BotPNI-->
<UL>
<LI>Prev by Date:
<STRONG><A HREF="msg00677.html">Re: [MUD-Dev] Character evolution</A></STRONG>
</LI>
<LI>Next by Date:
<STRONG><A HREF="msg00679.html">Re: [MUD-Dev] Re: Character evolution</A></STRONG>
</LI>
<LI>Prev by thread:
<STRONG><A HREF="msg00236.html">Collision detection</A></STRONG>
</LI>
<LI>Next by thread:
<STRONG><A HREF="msg00221.html">Re: (fwd) Re: LP: How does it work?</A></STRONG>
</LI>
<LI>Index(es):
<UL>
<LI><A HREF="index.html#00678"><STRONG>Date</STRONG></A></LI>
<LI><A HREF="thread.html#00678"><STRONG>Thread</STRONG></A></LI>
</UL>
</LI>
</UL>
<!--X-BotPNI-End-->
<!--X-User-Footer-->
<!--X-User-Footer-End-->
<ul><li>Thread context:
<BLOCKQUOTE><UL>
<LI><STRONG>Re: [MUD-Dev] Multi-threaded programming under Linux</STRONG>, <EM>(continued)</EM>
<ul compact>
<LI><strong><A NAME="00225" HREF="msg00225.html">Re: [MUD-Dev] Multi-threaded programming under Linux</A></strong>,
Jeff Kesselman <a href="mailto:jeffk#tenetwork,com">jeffk#tenetwork,com</a>, Wed 23 Jul 1997, 13:18 GMT
</LI>
</ul>
</LI>
<LI><strong><A NAME="00223" HREF="msg00223.html">Re: [MUD-Dev] Graphical MUDs</A></strong>,
Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Wed 23 Jul 1997, 13:04 GMT
<LI><strong><A NAME="00222" HREF="msg00222.html">Collision detection</A></strong>,
coder <a href="mailto:coder#ibm,net">coder#ibm,net</a>, Wed 23 Jul 1997, 12:21 GMT
<UL>
<li><Possible follow-up(s)><br>
<LI><strong><A NAME="00236" HREF="msg00236.html">Collision detection</A></strong>,
coder <a href="mailto:coder#ibm,net">coder#ibm,net</a>, Fri 25 Jul 1997, 09:29 GMT
</LI>
<LI><strong><A NAME="00678" HREF="msg00678.html">Collision Detection</A></strong>,
Cynbe ru Taren <a href="mailto:cynbe#laurel,actlab.utexas.edu">cynbe#laurel,actlab.utexas.edu</a>, Tue 19 Aug 1997, 21:26 GMT
</LI>
</UL>
</LI>
<LI><strong><A NAME="00221" HREF="msg00221.html">Re: (fwd) Re: LP: How does it work?</A></strong>,
coder <a href="mailto:coder#ibm,net">coder#ibm,net</a>, Wed 23 Jul 1997, 11:46 GMT
<UL>
<li><Possible follow-up(s)><br>
<LI><strong><A NAME="00237" HREF="msg00237.html">Re: (fwd) Re: LP: How does it work?</A></strong>,
coder <a href="mailto:coder#ibm,net">coder#ibm,net</a>, Fri 25 Jul 1997, 09:29 GMT
</LI>
</UL>
</LI>
<LI><strong><A NAME="00215" HREF="msg00215.html">Re: [MUD-Dev] Multi-threaded programming under Linux</A></strong>,
S001GMU <a href="mailto:S001GMU#nova,wright.edu">S001GMU#nova,wright.edu</a>, Wed 23 Jul 1997, 03:52 GMT
<UL>
<LI><strong><A NAME="00231" HREF="msg00231.html">Re: [MUD-Dev] Multi-threaded programming under Linux</A></strong>,
clawrenc <a href="mailto:clawrenc#cup,hp.com">clawrenc#cup,hp.com</a>, Thu 24 Jul 1997, 07:11 GMT
</LI>
</UL>
</LI>
</UL></BLOCKQUOTE>
</ul>
<hr>
<center>
[ <a href="../">Other Periods</a>
| <a href="../../">Other mailing lists</a>
| <a href="/search.php3">Search</a>
]
</center>
<hr>
</body>
</html>