Re: [Algorithms] N-body processing

[Dave E. <eb...@ma...>]

From: "Matthew MacLaurin" <ma...@me...>
To: <gda...@li...>
Sent: Friday, August 18, 2000 1:02 PM
Subject: RE: [Algorithms] N-body processing

> Hey! Check out the swept sphere stuff at UNC! It's the newest thing I've
> seen in a while for fast proximities and N-Body sim. Even more interesting
> is what they're using it for -- it appears ideally suited to huge poly
> counts. I posted the link last week.

I put swept sphere stuff into NetImmerse when UNC was
starting to look into the topic as an alternative to using
OBBs in a tree.  I had asked Stefan Gottschalk at his
dissertation defense if he had considered such bounding
volumes, but he indicated 'no'.  They work out quite well
because they rely on squared-distance calculations that
turn out to be less expensive (on average) to calculate
than the separating axes, especially so in situations of
close proximity.

Code for building trees of spheres (points a specified
distance from a point), capsules (points a specified
distance from a line segment), and lozenges (points a
specified distance from a rectangle) is at my site, the
MgcContainment.html page.   I eventually plan on
putting the code at my site for the collision detection,
but it may take a couple of months.

--
Dave Eberly
eb...@ma...
http://www.magic-software.com