Path: chuka.playstation.co.uk!news
From: Robert Swan <rs108@mdx.ac.uk>
Newsgroups: scee.yaroze.freetalk.english
Subject: Re: Collision Detection Shortcut Update
Date: Tue, 17 Feb 1998 13:29:21 +0000
Organization: I wish!
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James Shaughnessy wrote:
> 2) I suspect that collision in 3D fighters is a LOT simpler than
> using a load of collision spheres all over them -- that would be
> too expensive I'd say.  The way I would do it is just use simple
> logic tests based on what move one character is doing, with what the
> other character is doing and their distance apart (they are always
> either looking at each other or away (and moves are limited) so you
> can think of collisions in a simple 2D form.)  Then all you do is
> match the variables with what each character's body is like (height /
> arm reach etc.) so it appears as though when a hit a takes place it was
> due to the hand literally touching the face in 3 dimensions.  Which is
> nice.

I think that is correct about 3D fighting games. I remember back when 
they were converting Virtua Fighter to the Saturn, they released a 
demo with only two moveable characters, but they said they had yet to
implement the collision/move tables, suggesting that all contact
permutations are precalculated and then its just a simple logic
test. Having said that, in these days with such complex movements
possible, calculating these tables beforehand would be a huge 
numbercrunching task, compared to simpler, more general routine of
testing bounding volume intersections (even though this is much
slower in execution) I'd be VERY impressed for a home developer to
attempt this :)

Robert Swan
rs108@mdx.ac.uk
http://www.netyaroze-europe.com/~middex2