p.s. on un un-imagine note, how do I add errors-to to the header, as I know I'm
going to get a lot of bounces from this letter.
##
Subject: POUR THE FIRE OUT
Date: Wed, 23 Sep 1992 00:16:52 +0300
From: "Alex. Paterakis-UN. LA VERNE" <apat@leon.nrcps.ariadne-t.gr>
I don't know if emulating FIRE or PURING WATER can be covincing but my attempts are certainly not. I've tried the wierdest attempts but nothing seems to please me.
I've seen FIRE before on candles..but REAL MOTION FIRE..never !
If anyone has the faintest idea..ANYTHING !..please help
OVER & OUT...ALEX
##
Subject: Imagine 3.0 & Electricity
Date: Tue, 22 Sep 1992 17:59:33 -0400
From: Jason B Koszarsky <kozarsky@cs.psu.edu>
Part 1:
Does anyone know if Imagine 3.0 supports AGA? I would assume it did but you
never know for sure.
Part 2:
I asked about making electricity crawl over objects before but I didn't get any
responses here. Does anyone have techniques for simulating this in Imagine 2.0?
Jason K
##
Subject: Re: Imagine 3.0 & Electricity
Date: Tue, 22 Sep 92 18:58:17 CDT
From: Wayne Haufler 283-4160 <haufler@sweetpea.jsc.nasa.gov>
Jason B Koszarsky <kozarsky@cs.psu.edu> writes:
> Part 2:
> I asked about making electricity crawl over objects before but I didn't get
> any responses here. Does anyone have techniques for simulating this in
> Imagine 2.0?
It seems to me that electrical sparks are somewhat fractal in nature.
I've tried to use one of Essence textures to make growing cracks on an object.
But not with much success yet. If that can be done,
perhaps crawling electricity could be done similarly, but with a very
bright color instead of a dark color.
Essence has a variety of fractal and turbulent textures which might work,
like bandfractal, radialfractal, fractalcolor, veinedmarble (nah),
(not sure about the names)
Generally, though, these fractals define the bounds between two color regions,
It may help to think of it in another way.
Crawling electricity, if memory serves, looks like many small blue glowing
worms marching sideways chaotically (fractally) but in a rough connected line.
8^)
A traveling vein of marble might work, with the distance between veins
set very big, and the colors and sharpness set appropriately.
Or a bandfractal with a narrow width, but that might be too straight.
Essence, in case you don't know, is a library of algorithmic textures for
Imagine by Steve Worley and Glen Lewis.
Ah, wait! Let me quote from page 88 of the Essence manual (ok, Steve?)
For bandfract, bandturb, ringfract, rightturb, shellgract, shellturb:
"One application of these textures are good at representing a traveling
wave, like a firestorm or a shock impact. The fractal perturbation
will give a ragged, natural appearance.
For example, you might be making a space battle, where a bolt of energy
hits the side of a ship. You could use the texture "Shellturb" to
apply a bright blue ring centered at the impact point. If you expand
the starting radius of the shell over time, you can make the blue color
expand away from the impact. You might also morph the Fade value to
slowly decay the strength of the blue band, so when it is farther from
the impact point, it has become less powerful like it has spent
itself."
That sounds a lot like crawling electricity to me, from a distance anyway.
Happy rendering!
__ Wayne A. Haufler [Christian/SW Engineer/XWindows/Amigan]