
Pixar Universal Scene Description - aethertap
https://github.com/PixarAnimationStudios/USD
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mp3jeep01
Currently reading The Pixar Touch by David A. Price and they talk a lot about
the types of software and standards for rendering they had to create over the
years. Incredibly interesting looking back at what they were able to achieve.
A talented crew for sure.

For those interested: [https://www.goodreads.com/book/show/2632830-the-pixar-
touch](https://www.goodreads.com/book/show/2632830-the-pixar-touch)

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Cyph0n
Thanks for the recommendation. I've always been interested in the rapid rise
of Pixar and the consistency in quality they've maintained for these past two
decades.

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santaclaus
30 years! Although they started out in hardware... talk about a pivot.

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mp3jeep01
Every step of the way they were scheming how to get to feature films --
everything in between sounds like a means for resources (money, hardware,
people, so on so forth).

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bazzargh
There was a demo of some USD-related software at SIGGRAPH, for context:
[https://www.youtube.com/watch?v=JmH4KYcmHOo](https://www.youtube.com/watch?v=JmH4KYcmHOo)

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vec
Hey! That's our company's flagship laptop in the wild!
[https://system76.com/laptops/bonobo](https://system76.com/laptops/bonobo)

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rasz_pl
your company? You work for Clevo in China? because this is Clevo P870DM3-G aka
Sager NP9873

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Hondor
It looks exactly the same but with a different logo. However the speaker in
the video does seem to have the system76 (Bonobo) logo on his

Clevo: [http://www.gentechpc.com/Sager-
NP9873-S-Clevo-P870DM3-G-nVid...](http://www.gentechpc.com/Sager-
NP9873-S-Clevo-P870DM3-G-nVidia-GTX-1080-p/sager-np9873.htm)

Bonobo:
[https://system76.com/laptops/bonobo](https://system76.com/laptops/bonobo)

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nitrogen
I never knew anyone was building laptops with dual desktop GTX1080s, but you
pay for it by having to lug around _two_ 330W power supplies.

Since someone from System76 is on the thread, can you comment on why the
System76 version uses a 1080p@120Hz screen instead of 1440p@120Hz like the
Clevo?

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smegel
Just why. If you want to work on the go, clean up your damn inbox!

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xorgar831
That's interesting they didn't just collaborate on alembic.io, despite being
sister companies.

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mrmrben
Alembic is a baking format. Slightly different use cases.

Usd has support for Alembic baked nodes:
[https://github.com/PixarAnimationStudios/USD/tree/2eb01f5cd4...](https://github.com/PixarAnimationStudios/USD/tree/2eb01f5cd4c2dae4e1ef9912ca27a93083bb6ef4/pxr/usd/plugin/usdAbc)

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TeMPOraL
Could you explain what "baking" means in computer graphics?

I spent a few minutes googling, and all I've learned so far is that:

\- there isn't "baking", there's "texture baking", "light baking", and many
other "<insert noun here> baking"

\- it seems to mean any kind of precomputing stuff

\- apparently the term was coined by Pixar in some paper

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CyberDildonics
> precomputing stuff

Correct. In this context it means turning the geometry into frame by frame
mesh data so that your animation isn't dependent on anything like bones, cloth
simulation, muscle/skin simulation, soft or rigid body dynamics, inverse
kinematics in the rig, expressions on the bones of the rig etc.

Not only does it break dependencies, but it is also easier to get that
geometry into another part of the pipeline like effects, lighting and even
compositing.

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solidangle
So does a renderer such as RenderMan use a baked format like Alembic or a
format like USD?

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joeld42
Neither, and both. Lets say you have a scene with a cup of coffee spilling
onto a desk...

The overall description of the scene, where the desk is, the lights and
materials etc, could be stored in a USD scene.

Some tool would read this and generate an intermediate file in RIB format.
This would be what a RenderMan renderer actually reads.

For the fluid sim itself, the generated RIB file might contain a reference to
a plugin which points to the baked Alembic data, which would be a directory
with one alembic file per-frame of mesh data representing the fluid surface.

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gfaure
I noticed that their coding style consistently uses the spelled-out Boolean
operator keywords "not", "and", "or". Can't think of any other C++ codebases
that use this -- can anyone else?

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kraftman
>> Universal Scene Description (USD) is an efficient, scalable system for
authoring, reading, and streaming time-sampled scene description for
interchange between graphics applications. What does this mean for the layman?
I got a 404 for the 'getting help with USD' link

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mmel
I am going to hazard a guess as nobody else responded. They have a lot of
different tools for different aspects (animation,mocap,shaders,texture
painting, modelling, rigging, final render etc) and a USD allows them to
quickly back-and-forth between the different stages on as-yet incomplete
scenes to preview final renders, make fine adjustments further up and down the
pipeline to accomodate for changes made elsewhere.

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United857
How does this compare with DAE, which seems to be the existing standard for
this?

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dagmx
I'm not sure if anyone really uses DAE at all if they can help it. Collada is
an attrocious format and everyone has switched to Alembic or FBX long ago.

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billconan
is this a scene graph library? does it support animation? or each frame is
just a still 3d scene.

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dagmx
It is a scene graph and scene descriptor, and an (optional) geometry baking
format along with an AZDO GL viewer

