
One of the most amazing physics engines I’ve ever seen - jmillerinc
http://vimeo.com/13457383
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SandB0x
Rather than sharing a blog post about a cool thing, why don't we share the
cool thing directly?

The video is at <http://vimeo.com/13457383> \- you can get to this page by
simply clicking the Vimeo logo on the embedded clip. From here, you can click
on Thiago Costa's profile <http://vimeo.com/thiagocosta/> and have a look at
all of his 48 videos, and find a link to his website (which looks pretty
interesting): <http://thiagocosta.net/>

The CrunchGear article doesn't really add anything, other than a layer of
indirection.

Having said that, the video is awesome and thanks for sharing :)

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guelo
OTOH, the submitter might not have found these cool videos without TechCrunch
so some appreciation via sending them traffic seems reasonable.

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euccastro
Showing appreciation by putting them between us and the beef is a bit like
tipping a waiter with the cash of the people that ate with you, without asking
them.

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bd
If you like physics simulations, there were some very cool papers at this
year's SIGGRAPH:

<http://www.youtube.com/watch?v=KMsc48e41AQ> (A Practical Simulation of
Dispersed Bubble Flow)

<http://www.youtube.com/watch?v=GyfB_vQHMAo> (Physics-Inspired Topology
Changes for Thin Fluid Features)

<http://www.youtube.com/watch?v=7Who8EpbvCY> (A Multiscale Approach to Mesh-
based Surface Tension Flows)

<http://www.youtube.com/watch?v=nHH8N_lNZzI> (Rigid-Body Fracture Sound)

<http://www.youtube.com/watch?v=gx80u6hJT6o> (Efficient Yarn-based Cloth with
Adaptive Contact Linearization)

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maximilian
Whats the deal with the rabbit that keeps popping up? Is it the physics
simulation's Lena?

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JabavuAdams
It's the Stanford Bunny.

<http://www.cc.gatech.edu/~turk/bunny/bunny.html>

It was preceded by the Utah Teapot. There's also the Cornell Box, for global
illumination testing.

So, yeah, like Lena.

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rbanffy
> It was preceded by the Utah Teapot

Teapotahedron, please. It's the sixth platonic solid.

~~~
Gibbon
I also vaguely remember one of the popular 3d software packages having a bald
eagle as one of the primitives.

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Groxx
Interesting... but not all that amazing, really. There's a rather glaring
error, repeated many times, which many engines suffer from. Twitchy,
spontaneous motion:

1) at ~23 seconds, look at the top-1/3, left-1/4 location. Chunks of particles
_literally_ spontaneously accelerate towards each other. Towards the top-most
corner of the top platform, there's even a little snake-like thing that starts
inch-worming around for no apparent reason, and a blob that leaps into the air
at _far_ higher velocity than it is made of.

2) with the 8-second cloth clip, note the twitching as the cloths try to find
a stable resting point. Remind you of stacked objects in the Source engine[1],
perhaps? Jump on top of them and it's like walking on an earthquake.

3) note how long the left block at ~2:40 takes to settle (almost, it doesn't
actually), and the weird thrown-on-top chunk that twitches up and down a
couple times, and then gets a burst of energy right when it starts fading out,
moving _up_ , and _faster_ than the pieces it's touching, and without any
visible ripple which could account for it.

If it's done by _one person_ (Thiago Costa?), yes, very impressive job, that's
a _lot_ of work. But overall... more of the same.

\---

[1]: chosen only because it's a relatively modern engine, and one many are
familiar with.

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javanix
The article seems to have the wrong idea about what that engine is.

While impressive, it was developed using ICE - a rendering package addon for
Softimage, and is probably not able to be calculated in anything remotely
resembling real-time.

So no, you won't be able to tell what religion Kratos is unless it's during a
cutscene.

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NathanKP
Actually, it shows in the first video that you can interact with the materials
in real time in the 3D graphics package, albeit with less accuracy. So it
shows the use of the mouse to drag a data point and stretch a squishy, gummy
object that breaks and snaps back. That was real time interaction. Of course
it didn't have nearly as many data points as the high res renders at the
start, but I was still very impressed by that real time use of the engine.

That means that if can surely be used for 3D games as well.

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javanix
Maybe, but I doubt it.

Those real-time versions for modelling packages tend to be really rough
approximations using the same code, and not worth the time it would take to
optimize for a real, resource-restricted environment like a gaming console.

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NathanKP
For a standard modern game rough approximations of the quality shown in that
video are more than adequate for something simple like a loincloth. It might
not do for approximating an entire lake or body of water, but for simple
things it would work just fine.

Even gaming consoles are limited by the number of polygons they can render, so
the physics engine, if running in a game, wouldn't have to consider all the
approximation points that were used to generate the high res renders at the
start of the video for instance.

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gfodor
If this isn't real time, then this isn't that impressive. This type of fluid
rendering has been possible for almost a decade:

<http://graphics.stanford.edu/papers/water-sg02/>

That said, if it is realtime, then yay.

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ewjordan
No way this is real time, not even close. There's a frame rate counter visible
in a couple of the videos (see <http://vimeo.com/7455632>, for example), and
it's going at about 3-4 fps for the lowest detail models, which only have
somewhere around 1000 points. The highest detail ones have millions, and
probably took hours if not days to render.

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mikecane
Anyone out there from Pixar? How does this compare to what you guys have? I
still gape at The Incredibles, especially the fine hair animation. But what I
saw in the demo here of the cloth looks like something Pixar would want to
have. Let me caution everyone, however, I haven't seen UP!, so perhaps Pixar
has this or surprassed it.

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sliverstorm
Based off Pixar's recent movies, and a quick retrospective look at their older
movies, I suspect they are sticking to their current level of realism as a
matter of style, and only making slight subtle tweaks and improvements. If you
compare their old movies to the newer ones, primarily you notice textures and
objects are sharper, clearer and more detailed, movements of characters are
more natural, and faces are more lifelike.

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smackfu
Does charcoal really act exactly like water?

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thefool
No, the particles are bigger. Duh.

To be fair it looked a little different than water.

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smackfu
Actually, I think real charcoal would have more dust sized particles.

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Rhapso
The friction seems a bit off, but it looks great.

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maushu
Funny, this reminds me of all those old 2d mass-spring engines. I believe
there was a cool one like asteroid where you could shear off one of your
engines making your ship spin around. It was open source too. Can't remember
the name.

EDIT: Ah, found it: <http://www.alecrivers.com/physical/overview_physics.htm>

There is even a older one that was an form-based application for windows where
you could edit particles and connections. Pretty fun.

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elblanco
I was thinking the same thing regarding xspringies...

 _edit_ Your link reminds me of Phun <http://www.phunland.com/wiki/Home>

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nnash
Definitely impressive. I can't imagine the framerates with this engine being
practical though.

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GrandMasterBirt
Pretty incredible! Now I'd love to see them take high quality video
inside/outside a demolition of a building and compare that to the simulator.
For video games and such though, this would be incredible already. Is this
sort of engine used to design cars and such?

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levesque
This stuff always has a warm and fuzzy feeling to it, but imagine the pain of
implementing a full game with such physic effects, setting all the
particles...

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eru
What do you mean by "setting all the particles"?

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sparky
I'm guessing "describing the material and construction properties of every
object such that it can be moved, collided, broken, and deformed
convincingly." "Convincingly" typically isn't quite what you want either, you
usually want "spectacular" which means hand tuning for all breaking/deforming
events of interest. Movie effects, for example, start with pure simulation,
but nearly always have lots of knobs for artists to play with to give the
intended effect (e.g., the last page of this article
[http://www.wired.com/entertainment/hollywood/magazine/16-01/...](http://www.wired.com/entertainment/hollywood/magazine/16-01/ff_animation)
).

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lwhi
I'm sure APIs would be implemented which would provide games developers with
programmatic 'knobs' for fine-tuning.

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smallblacksun
The problem is that the fine tuning only works for one particular situation.
In a game, it has to work for every situation the user can create.

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eru
Then just don't bother with manual fine tuning. Level designers are using
object libraries even now, where they just take a pre-made chair, instead of
constructing them out of basic polygons every time.

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lowkey
Man, I am so proud to be a Montrealer right now. This is an amazing example of
the Creativity + Talent + Technology = Innovation that exemplifies this city.

Vive le Montréal! Oh and kudos to Thiago Costa. This is just awesome!

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frangossauro
Thiago costa is brazilian...

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lowkey
Living in ...

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openfly
On the negative side, the potential use of an engine as advanced as this in
the world of 3D porn will almost certainly result in more furry sex.

