
Pixar open sources production animation code, patents - cpeterso
http://www.theregister.co.uk/2012/08/13/pixar_open_sources_open_subdiv/
======
zach
Is it too much to hope that someday some of the software at the heart of
Pixar's physics simulation systems could be released?

Oh man, that would be awesome. When I went to the legendary SIGGRAPH 2001
Physically Based Modeling course with David Baraff and the late Andy Witkin,
they discussed all the ways we could avoid having our numeric solvers "blow
up" (basically, when numerical values change too quickly to figure out how to
reasonably estimate them). Then Andy somewhat sheepishly mentioned that they
don't actually deal with these problems, since their team at Pixar created a
direct solver they actually used instead, which solved the many necessary
equations symbolically instead of numerically.

This was 2001, so few in attendance had the ability to go off and write an
effective direct solver for their project even if they had the right
background to do it. So we made do with numeric solvers and patched over
occasional blow-ups. That's a picture of how things go. It's not surprising
that the pipeline in Emeryville was far more advanced, seeing how Witkin and
Baraff created the Maya physics engine as a warm-up for their Pixar system. By
now, there are better solvers in many physics systems... yet how much more
insanely awesome must Pixar's simulation software be by now?

It's easy to see that this kind of software is highly strategic — Pixar hired
world experts to work on this and it must be extremely well-seasoned code,
with countless tricky "gotchas" compensated for. It's not hard to see how that
gives them a clear competitive advantage.

On the other hand, the potential is enormous. This system is the masterwork,
even the life's work, of unbelievably talented people. Erin Catto's work and
generosity with Box2D has shown the massive innovation and even cultural value
of code like this. How many more amazing things could be created with a
simulation engine of the quality Pixar is sitting on?

So although I'm not holding my breath, it would be amazing to see even a small
part of their physics simulation in a future open source release. Is that
realistic? I have no idea.

~~~
ajg1977
Pixar and ILM sim systems are based on PhysBAM.

<http://physbam.stanford.edu/>

------
nezumi
Subdivision surfaces as implemented in RenderMan have been a thorny issue in
VFX for many years. Most production facilities wind up implementing their own
version of subdivision surfaces for other production tools, but still rely on
Pixar's implementation for rendering. The nature of the patents in Pixar's
implementation make it hard for individual facilities to match the final
subdiv output, and risky to release their own open-source implementation for
fear of revealing a patent dependency.

So this has been a long-time coming, and while the quality of Pixar's
implementation is undoubtedly welcome, the main advantage to studios is
relaxation of the patent requirement - something Pixar should have done years
ago, since all anybody wanted to do with those patents was better utilize the
tools they had licensed from Pixar in the first place.

~~~
berkut
The main reason for this is probably due to the fact that within the last
three years, the artists at Pixar have wanted to start using off-the-shelf
software for modelling, texturing, animating and compositing, instead of in-
house tools as previously.

So now they're using Maya, Modo, Mari and Nuke internally, and these apps need
to have support for subd to match what PRMan will output.

~~~
astrodust
Is the Disney division using significantly different tools from Pixar? The two
were entirely separate companies until the merger and an upheaval in the
workflow that significant is not usually so easy to manage.

------
kine
My initial reaction to this was, "Why would Pixar do this and remove such an
advantage that they hold against Dreamworks and other animation companies?"
And then it dawned on me, the animation is such a small piece of why we love
their movies. We love them for their characters and their writing and their
stories. The animation is the glue that ties it together so this is actually
really rad. Now that people can use this to animate as well as Pixar, it's
time for everyone to tell the best stories they can and capture the hearts of
future generations, just like Pixar has.

Side question: If Jobs were still alive, do you think this would have
happened?

~~~
orenjacob
In the past, Pixar chose to hold certain patents close to its chest, and then
when 3rd party application developers chose to implement similar features,
they had to avoid the patents. This meant that industry standard 3rd party
software sometimes had inferior and/or broken implementaions of certain,
fundamental technologies. Which caused much frustration when we (Pixar.. I
used to work there) started to use those same 3rd party packages ourselves in-
house.

Instead of that, how about ... do the research, do the engineering, patent the
correct approach, open source a reference implementation, license it properly,
and thereby force the industry's hand to "do it the right way" so that Pixar
can take advantage of 3rd party tools that implement those particular
technologies correctly.

+1 to Manuel, who's been working on this stuff for a while. Cool to see this
happen.

~~~
laserDinosaur
Ha, that's a strange disadvantage of patents I'd never thought of. Do you
think this happens much with patents outside of this example?

------
snogglethorpe
The Pixar code seems to be released under the "Microsoft Public License" (Ms-
PL), which is reportedly* (and no doubt intentionally) incompatible with the
GNU GPL.

So it's a nice gesture, Pixar, but, well ... muh.

[I am curious what Pixar were they thinking when they decided to use the Ms-
PL... Or was it just ignorance about Open Source?]

* <http://www.gnu.org/licenses/license-list.html#ms-pl>

~~~
berkut
Well it's pretty obvious - they want products like Maya, Modo (already has
it), SoftImage, ZBrush, Houdini to include this in the future, and they're not
going to include GPL stuff in commercial products. LGPL might have been an
option though...

~~~
snogglethorpe
I suspect they could have easily found a more FOSS-friendly license which
achieves their goals. The exact license depending on the exact goals, but
presuming the "normal" GNU GPL isn't appropriate, the GNU LGPL or BSD/MIT
licenses might be possibilities.

The Ms-PL, on the other hand, seems to be a license which is gratuitously
incompatible with the GPL, simply to be incompatible.

I've seen projects where the README essentially stated "We hate the FSF, so
we're using this roughly equivalent and yet incompatible copyleft license to
piss them off," but I don't think Pixar are jerks, so I'll put this choice
down to simple ignorance.

------
kevinconroy
Here's direct link to github repo:
<https://github.com/PixarAnimationStudios/OpenSubdiv>

------
lemming
This is pretty cool. I haven't followed graphics tech in a while, but
Subdivision Surfaces are one of the most important modeling primitives around.
Back in the day when Catmull and Clark first developed them Pixar held a
patent on them and it was pretty unclear how aggressive they'd be defending it
- the controversial removal of Larry Gritz's BMRT didn't bode well. It's great
to see them making steps towards an open model at last.

------
bendoidic
I love this wish list item: "John Lasseter loves looking at film assets in
progress on an iPad. If anyone were to get this working on iOS he'd be looking
at your code, and the apple geeks in all of us would smile."

------
Anon84
There's also an Open Source clone of RenderMan itself...

<http://www.renderpixie.com/>

which (I believe) has received some official support from Pixar. More
information:

<http://en.wikipedia.org/wiki/Pixie_(renderer)>

EDIT: Wikipedia link

------
caublestone
I was just contemplating the idea of open source film and that it could only
occur in animation and it would be especially helpful if the Pixar source code
was open. Now it's time for the creative Linus to emerge and start directing
content creation to make awesome open source films.

~~~
a3_nm
This already exists, to some extent. The Blender Foundation has produced three
open source animated short films using their open source Blender engine. They
are pretty cool.

------
mtgx
Does this mean Valve's Source Filmmaker can incorporate some of this stuff
now, so anyone can make Pixar-quality movies in the future?

~~~
iamdave
_Pixar-quality movies_

This is purely subjective and opinion, but it's hard to qualify something as
Pixar-quality based on looks alone. Supplemental to the aesthetics and
animation of a Pixar movie are the stories, characters, themes and tones woven
_into_ the aesthetics.

Just my opinion, though.

~~~
Synaesthesia
True, but their aesthetics have always been on the current edge of 3D
technology IMO, and it shows

------
leetrout
That is pretty rad. Nice to see that support for Alembic is on the wish list.
Hopefully some of the other studios will contribute back. I've been watching
from the side lines hoping to see a robust framework / toolkit emerge in open
source that deals with some of these lower-level issues. (Blender has pretty
much nailed the high level tool kit).

If anyone is interested and didn't already know, ILM & Sony made a splash into
open source last year with Alembic <http://www.alembic.io/>

------
papaver
pretty epic pixar, thanks! good way to set an example for the rest for the fx
community on sharing.

have to say im pretty impressed with the state of the code.

love it when i see ++index in for loops! props.

------
DigitalSea
Wow, just wow. While animation isn't my foray it sure looks like a lot of time
and effort has gone into Subdiv only for them to give it away and let you use
it for anything. Pixar are amazing and not to mention the end result of Subdiv
is as equally as amazing.

~~~
Cogito
Perhaps even more promising is the effort they appear to be putting in to
maintaining the open-sourced project.

Obviously Pixar is still using this library, and would love to get fixes and
features to fold back into the upstream project, however they are also
actively managing and responding to issues being raised. This speaks volumes
to how serious they are about supporting this software in its open-source
form. I hope this becomes another successful case study of how to do open
source, and provides useful feedback and additions for Pixar.

