Subject: Re: LW4.0 and physics , an open letter to NewTek
From: Allen D Hastings <[email-masked]>
To: [email-masked]
Date: Sat, 25 Feb 1995 01:17:48 -0800

>Ernie Wright <[email-masked]> writes:
>
>> Naturalistic
>> motion paths can be calculated as an energy minimization (Luxo Jr.), but
>> it's extremely compute-intensive and a lot more complicated than f = ma.
>
>NO WAY.
>
>Luxo was animated by hand. NO minimization equations were used, NO
>procedural animation was used, it was all the skill of the animator
>(in this case, John Lasseter). This is The Pixar Way. Later, some
>academics have tried to show that they could use math to make
>luxo-like animations (a lamp that leapt).  It was very clever, but
>never answered the more fundamental questions: is this a young lamp,
>or an old one? Is it happy, or sad? And they never remotely approached
>harder physical tricks like wiggling your base off-balance to waddle,
>or how to ride on a ball :) 
>
>Truly elegant tools provide you with the means to do procedural
>tricks, but also will provide the animator with the tools he REALLY
>needs to make convincing animation.
>---- Kevin Bjorke ---- Animation Scientist ---- Hi Tech Toons ----

I'm pretty sure Ernie was referring to the paper by Witkin and Kass
in the '88 SIGGRAPH Proceedings, which describes computing Luxo's
motion under such conditions as minimizing muscle power (this is no
doubt the paper that Kevin is thinking of too).  I definitely agree
with Kevin that skilled human animators beat procedural tricks (for
the next few years at least).  It was interesting to hear two of
the Jurassic Park animators, in response to a question from the
audience at a local SIGGRAPH meeting, say that they didn't really
even want fancier physics tools - they preferred to hand animate
almost everything.

Getting back to LightWave, let me just say that there will be some
inverse kinematics features built into 4.0, but dynamics will be
left to plug-ins, which is as it should be I think, considering
that physical simulation is such an open-ended topic.
 
- AH