
Moving Remy in Harmony: Pixar's Use of Harmonic Functions - ot
http://www.ams.org/samplings/feature-column/fcarc-harmonic
======
dalke
This looked familiar but there's no date on the article for me to be sure. An
HN search, however, finds 4 previous submissions from April, 2010 which link
to the same page or (likely) URL variations thereof. The one with comments is
[https://news.ycombinator.com/item?id=1269248](https://news.ycombinator.com/item?id=1269248)
.

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jwmerrill
Does anyone know if using relaxations to compute interior coordinates is still
the state of the art?

Once you've done this, do you end up computing a dense MxN matrix-vector
product for each component of an internal mesh point displacement, where M is
the number of internal mesh vertices, and N is the number of cage vertices?

It seems like you could do much better by exploiting the fact that nearby
interior point displacements are similar, using a fast multipole method:

[http://math.nyu.edu/faculty/greengar/shortcourse_fmm.pdf](http://math.nyu.edu/faculty/greengar/shortcourse_fmm.pdf)

If anyone here is an expert, has this idea been tried and discarded for some
reason?

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kclay
O how I hated to do animation, if you didn't build your character correctly
you would get all types of bends and pops when trying to animate. I rather
just stick to character modeling, sadly I switched majors since I realized it
would be hard to get into a good job afterwards .I already did all the basic
sutff, did superbowl coverage animation for news station when I interned in
HS, as was at the top of my class in college but I would of needed to move to
get any challenge, which I wasn't ready for at that time. O well.

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geon
Why don't they just use bones like everyone else?

~~~
harywilke
they do. they bones control the cage mesh. before to maintain volume of your
character mesh, you would bind latices to the bones to control your character
mesh. but that wasn't a very elegant solution as latices are box shaped and
your mesh is arbitrarily shaped. also latices have a bunch of interior points
that need to be dealt with. so people used multiple latices, one for each
limb, one for head, etc. then you had to make sure the latices overlapped
nicely and played nice with each other. this new method uses an over sized low
res version of your mesh. much simpler. it also accounts for things that are a
pain when binding your mesh like finger joints. where your middle finger bone
might affect some of your pointer finger mesh.

the video from the paper explains it pretty well
[https://www.youtube.com/watch?v=egf4m6zVHUI](https://www.youtube.com/watch?v=egf4m6zVHUI)

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giantrobothead
I don't know about anyone else, but I'd pay to see a movie starring that
triangle.

~~~
Avshalom
How about a dot and a line:

[https://www.youtube.com/watch?v=OmSbdvzbOzY](https://www.youtube.com/watch?v=OmSbdvzbOzY)

~~~
giantrobothead
Yes! Score for you, my friend. Chuck Jones is one of my personal heroes. Got
to meet him at a book signing in my college years, and he was as personable
and humbly awesome as you'd expect.

