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From: teittinen@cc.helsinki.fi
Newsgroups: comp.graphics
Subject: Re: 3D Animation Source Code Wanted
Message-ID: <1685.25a3517f@cc.helsinki.fi>
Date: 4 Jan 90 13:37:03 GMT
References: <9170@cbmvax.commodore.com> <21550@mimsy.umd.edu> <21561@mimsy.umd.edu> <21562@mimsy.umd.edu> <9182@cbmvax.commodore.com> <1990Jan2.224220.4136@ux1.cso.uiuc.edu>
Organization: University of Helsinki
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In article <1990Jan2.224220.4136@ux1.cso.uiuc.edu>, mjw06513@uxa.cso.uiuc.edu (Mary J Winters) writes:
> I would very much like to learn the techniques used to produce fast 3D
> animation of wireframe objects. I assume it is done using only integer
> math, with optimization techniques such as multiplication/division replaced
> by shifts, lookup tables for trig/transcendental functions, etc. Can anyone
> point me toward a good source of information on these and similar topics?

How about calculating the possible views of the objects beforehand and
storing results in large lookup tables? First you must think that such a
table is mindbogglingly big, but when you think of it, you can leave out
e.g. mirror-images (cuts the table in half). And most of the PC's have
640 kB of memory anyway :-)  In fact some of the commercial animated
3d-games look like they are done this way (I don't know for sure, but
the objects don't always grow or turn smoothly). So calculate the object
in different angles, store the images in a table (I guess scaling can be
done while drawing), and draw the images on screen.

That should be fast enough.

-- 
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