Clouds - Simul software technology

[Chris Johnson]

Gotta do some clouds...just starting the research phase to see what's
out there.

http://www.simul.co.uk/

Anyone ever used this...last version of support was XSI 7.5?

--
Chris Johnson
3D Supervisor
Topix
www.topixfx.com

[Pete Edmunds]

Binary alchemy volume and shader plugin springs to mind

http://www.binaryalchemy.de/

[Marc-Andre Carbonneau]

What kind of clouds are you needing? What's the use of those clouds?
Have you checked Ozone 5? It's the clouds and atmospheric part of Vue by E-on Software.
http://www.e-onsoftware.com/products/ozone/ozone_5.0/

MAC

[Chris Johnson]

We have one artist working in Vue right now. How do you pronounce that
(view?) .

I'm yet to try the Binary alchemy shaders but I will. We've tried max
and Maya Fluids and our Compositor wasn't happy with the results...so
we're still in a trial stage and looking for options. They have to be
pretty art directed so I don't think a volume shader is gonna give us
the control you want. We'll give it a try though.

Any other suggestions welcome.

[tak...@earthlink.net]

There's also Terragen, you can export cameras to it as Nuke .chan.

-T

[Christopher Tedin]

Do you need "fly-thru" or background environment? Either way, you can't
go wrong with Vue. I use Vue 9 Studio to make great environments. The
spectral system is pretty good, and you can animate fly-through
animations. Should be able to bring in an XSI camera and
match-move/composite. Or, get the xStream version and plug it into
Softimage. Works with Mental Ray right inside Softimage. (Although I
haven't tested it, and don't have this version.) Rendering might be a
bit slow.

[Chris Johnson]

Not fly through but fly over head just above camera. We found with Maya
and Max the clouds had that default volume whispy edge look...we want to
get something I think looking a little thicker and at the same time have
the control of placement.

Thanks for the suggestions.

[Marc-Andre Carbonneau]

I'd go with basic background clouds in Vue and use Vue's metaclouds to "art direct" specific cloud shapes where needed.

-----Original Message-----
From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Chris Johnson
Sent: 14 f�vrier 2011 12:45
To: soft...@listproc.autodesk.com
Subject: Re: Clouds - Simul software technology

[Stefan Kubicek]

Since external apps haven't been ruled out and in case you have Max, you might want o look into DreamScape, Afterburn, FumeFX (all http://www.afterworks.com/) or
PhoenixFD (http://www.chaosgroup.com/en/2/phoenix.html)

> Gotta do some clouds...just starting the research phase to see what's
> out there.
>
> http://www.simul.co.uk/
>
> Anyone ever used this...last version of support was XSI 7.5?
>
>
>
>

--
-------------------------------------------
Stefan Kubicek Co-founder
-------------------------------------------
keyvis digital imagery
1050 Vienna Wehrgasse 9 Austria
Phone: +43/699/12614231
--- www.keyvis.at ste...@keyvis.at ---
-- This email and its attachments are
--confidential and for the recipient only--

[Steven Caron]

the first two maybe, but i didn't have much luck getting fumefx to do anything cloud like. i could get a better result faster with ICE and BA volume. phoenixfd i dont know anything about...

s

[Chris Johnson]

Yeah we didn't have much luck with Fume FX.

[Anthony Martin]

Built in particle volume/BA volume might very well get you close. You have the opposite problem to me. Last two jobs I did, the client wanted whispy clouds as opposed to well defined clouds, which the built in particle volume tools do quite well.

The problem I always find though is doing wide shots of lots and lots of clouds streaking overhead. Became very cumbersome and unstable (memory maxing out, looong renders times).

My current thinking is: develop particle/volume shader look. Render out big plates of the cloud. Use that to paint a 2.5d matte painting. Have lovely 3d volume clouds whizzing by in the foreground.

Anthony

[Morten Bartholdy]

We did 23 shots of aircraft flying in and out of clouds last year for a
feature, and went through exactly the same fase as you are in. Cloudwright
is nowhere near there yet, so forget that. Eventually we did all
cloudscapes in Vue with varying succes I might add, and for direct
interaction with hero clouds we used ICE/Volumetrics. These are difficult
for modeling realistic looking clouds seen from a distance, so Vue had to
provide that and for the foreground hero clouds, it was slow, tedious
work.

Vue is best for specific looks and types of clouds IMHO and the best
results (most realistic) was for the ones where the director allowed us to
use a lot of mist which made for very nice moody cloudscapes with
volumetric light. Be prepared for long rendertimes to get rid of or get
acceptable levels of grain/noise. We used Fusion with Revision FX
De:Noiser http://www.revisionfx.com/products/denoise/ extensively too.

We had limited succes with metaclouds - it is very hard to model a
believable thunderstorm with it. Better for little drifter clouds passing
by.

I find Ozone difficult and unstable so we used a workflow where we
exported animation via Vue Extreme, which is Vue inside Softimage, then
used Vue standalone to get the look right and render. For 1080p we had
rendertimes way beyond an hour per frame where clouds fill the frame, and
fog/mist makes for very noisy renders. ALso try and avoid flying inside or
through Vue clouds - it gets unbelievably slow, and it can be very hard to
see if you are actually inside a maybe 2% dense wisp of cloud at times,
but rendertimes soar when you do.

The upside was we had to get me a very fast machine and extra boxes for
the farm for this job :)

My 2 cents - good luck!

--
Best Regards

Morten Bartholdy
3D/VFX Supervisor

[Chris Johnson]

Thanks again everyone. Your opinions have saved me a ton of R&D time.

I know what your saying about the meta clouds...I'm already seeing the
limitations in "look".

Crossing my fingers on more RAM or a new box!!!!! ; )

--

[Marc-Andre Carbonneau]

Here's something that Vue expert Dax Pandhi did. Might be useful to you? Only 9 bucks!
http://www.cornucopia3d.com/purchase.php?item_id=8913

-----Original Message-----
From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Chris Johnson

[Schoenberger]

Hi

Hmm, the funny thing is that the very first reason the volume shader was
developed was because I needed to create a sky (time-lapse movement).
Some images of the first version 0.5 of the volume shader:
http://www.binaryalchemy.de/develop/shd_vol/img_prod/Weisse_Ameisen01.jpg
http://www.binaryalchemy.de/develop/shd_vol/img_prod/Weisse_Ameisen02.jpg
http://www.binaryalchemy.de/develop/shd_vol/img/maya_Cloud_Sky.jpg

If you want to use the build in volume with an "artistic" shape, then I have
a small collection of different shapes you can create:
http://www.BinaryAlchemy.de/develop/help/2d_3d_comparison.htm

The way I made it is just by plugging a fractal piped into the volume shader
and apply the volume shader to a cube.
The making of:
http://www.binaryalchemy.de/develop/shd_vol/vid/Making_the_Sky.wmv

But as someone in the thread already said, if you want clouds until the
horizon, it could get difficult as the memory usage does increase
exponentially with distance.
As you can see in the first images, the clouds are faded out or clipped by
trees.

One trick I used was to create multiple cubes.
So I could just place them where you see sky.
And if the camera rotates, only the cubes that are seen use memory.
And at last I used different cell settings and details the farther away.

Last but not least:
If you really want to define the shape of the clouds, then the best solution
would be to model the rough shape with polygons.
Then use the BA_mesh_distance shader.
I cannot show you my last project, but there I have made an inner building
with columns (imagine the inner view of a church or throne room)

The attached is not the best example, but this one has a polygonal shape.
But it is a good example for an artistic look.

Holger Schönberger
technical director
The day has 24 hours, if that does not suffice, I will take the night

|> -----Original Message-----
|> From: softimag...@listproc.autodesk.com
|> [mailto:softimag...@listproc.autodesk.com] On Behalf
|> Of Chris Johnson

[Steven Caron]

http://www.binaryalchemy.de/develop/help/2d_3d_comparison.htm

is this page in the softimage documentation? cause that helps a lot in visualizing.

i was wondering how would one get a simple falloff of density from the middle of the particle to the edges? i tried to use a cell scalar but had no luck. i essentially want to control that fallof from center of the particle to the edges and use it to blend in the different fractal scalar and cell scalar shaders.

s

[Schoenberger]

>is this page in the softimage documentation? cause that helps a lot in visualizing.

I am not sure, they wanted to implement everything...

 

The density of a particle has always a falloff from center to the edge. If you do not have one, then the global density in the volume shader is perhaps very high.

You can only control the falloff itself with the switch linear or cubic falloff.

 

And then apply the fractal/cell into the density shape input of the particle shader.

There are some images in the help above with the cell shader (bottom), anything in it you want to achieve?

 

Holger Schönberger
technical director
The day has 24 hours, if that does not suffice, I will take the night

 

 

 

---

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Steven Caron
Sent: Friday, February 18, 2011 12:58 AM
To: soft...@listproc.autodesk.com
Subject: Re: Clouds - Simul software technology

[Adam Seeley]

HI,

 

I'm sure I'm missing a basic concept here.

 

I've enveloped a mesh and animated it using a chain. 

When I add an Ice Simulation tree, the envelope animation no longer animates. 

I'm missing something quite obvious I'm sure, but how do I get the mesh to keep deforming using the envelope.

I want a simulated Tree so I can run some Weightmap calculations.

 

To see what I mean, run this to set up a simple enveloped anim

------------------------------------------------------------

CreatePrim "Cylinder", "MeshSurface"
Create2DSkeleton 0, -2, 0, 0, 0, 0, 0, 0, 0, 4
AppendBone "eff", 0, 2, 0
SelectObj "cylinder", , True
ApplyFlexEnv "cylinder;root,bone,bone1,eff", , 2
SaveKey "bone1.kine.local.rotz", 1, 0, , , False
Rotate , 0, 0, 90, siRelative, siLocal, siObj, siXYZ
SaveKey "bone1.kine.local.rotz", 25, 90, , , False
Rotate , 0, 0, -180, siRelative, siLocal, siObj, siXYZ
SaveKey "bone1.kine.local.rotz", 50, -90, , , False
Rotate , 0, 0, 90, siRelative, siLocal, siObj, siXYZ
SaveKey "bone1.kine.local.rotz", 75, 0, , , False

-----------------------------------------------------------

 

Then add a Simulated Ice Tree.

 

 

Thanks,

 

Adam.

 

 

 

 

	Adam Seeley Senior Animator, Commercials, UK T: +44 (0)20 7565 1000   E: adam....@primefocusworld.com@primefocusworld.com www.primefocusworld.com

[Robert Chapman]

Hi Adam,

it depends on what you want to do really,  normally we would point cache the animated mesh and then apply the simulated Ice tree to that, but for it to continue to work simply you could drag the envelope operator above into the post-simulation stack, or even go fancy and mute the envelope operator and apply the dual quaternation deformation in Ice..

[Orlando Esponda]

...And if your ICE tree depends on the envelope deformation you can also drag the ICE tree to the post simulation stack, above the envelope op

[Alan Fregtman]

It's a feature not a bug. :p As soon as you have "Simulation" in your stack, even with no ICEtrees to be found, anything below Simulation only evaluates on the first frame.

Like others pointed out you just have to bring up the Envelope op into the Simulation stack, below your ICEtree op. Should be fine. ;)

[Steven Caron]

i am trying to keep the particle fully solid for a certain range from inside to outside, then right at the edge shift to using some fractal or cell. i will try and send an illustration...

s

[Schoenberger]

 

Just increase the contrast in the fractal_scl shader.

If you have a default fractalsum, then set min/max contrast to 0,45 and 0,55

Then set the intensity of the "shape density" in the partilcle shader to 1.

 

Or increase the contrast slider in the volume shader (but I would go with tweaking the particles)

 

 

Hint: What a lot of people forget is to use the shader ball.

Works fine to see the contrast in the fractal.

And to see a sliced particle in the particle_density.

 

 

Holger Schönberger
technical director
The day has 24 hours, if that does not suffice, I will take the night

 

 

 

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Steven Caron

Sent: Friday, February 18, 2011 9:32 PM

[Steven Caron]

i use the shader ball exentsively but set grid so i can visualize the texture/scalar. i am going to try this right now...

[Steven Caron]

ok i had no luck... i comped this... i took a fractal scalar, with high contrast. 0.45/.55, 2 distortion, and 'small noise', scale of 1. then i just laid a shader ball render of the particle_renderer with no fractal plugged into density shape. i then set the parameter to 0.75.

i want it to be a density of 1 from the center of the particle to 3/4 of the distance away from the center, then i want to blend in a small noise.

steven

[Steven Caron]

hmmf... image got blocked...

[Vincent Fortin]

I too look forward to create realistic clouds in Soft. Here's some more examples from Holger's website that are interesting.

http://binaryalchemy.de/develop/shd_vol/img_prod/light_behind32.jpg

http://binaryalchemy.de/develop/shd_vol/vid/PT_textured_per_particle_lowres.mov

A lot of those examples are too noisy to my taste and feel a tad unnatural but I'm sure we've got everything for the task in Softimage. Not Softimage but the clouds in Legend of the Guardians were simply hand-made geometries filled with volume. Clever usage of fractals was mandatory but the little touch that made the hero ones stand out is the simulation added on top. A simple localized curl noise for example can really help breaking the procedural look from the textures.

Seeing how fast the community is responding to ICE, the addition of a voxel framework in it would potentially blow the competition away. I really really hope it will happen one day.

In the meantime, Houdini is ahead in terms of control. Here's some great looking examples:

http://vimeo.com/17975439

http://features.cgsociety.org/story_custom.php?story_id=3575

http://dnabox.com/?p=152

But for those who take to heart having a life fully lived, I agree, Houdini might not be an option.

Vincent

P/S: @Steven, my girlfriend just walked behind and asked "WTF, is that a hole in a bathroom?". No offence, I just has a good laugh and had to share ;-)

[Steven Caron]

lol that got me chuckling!

i have some clouds which i am quite happy with! but i still want to push it further. the houdini examples illustrate scale very well and i feel is the biggest draw back to the volume shader. on top of the large cellular cloud shapes we need noise that is 'displacing' the volume at a much smaller level. i dont mind layering the wispys on after with another render pass.

many good examples are here in the volumetric methods in visual effects course from siggraph 2010, notice the almost displaced look of the density... http://magnuswrenninge.com/volumetricmethods

the most important thing i get from those courses is the 'modeling' of the volumes. they talk about using curves,patches, polygons, points/particles, level sets etc. we only have one way and that is with points/particles. of course they aren't using mental ray, most of them use a proprietary volume renderer.

as i said i have had some good luck using a dense mesh emitter that uses ICE and hand modeling for my overall cloud shape, then doing stuff like using weightmaps and turbulence to modify the positions/size of particles. feeding that per particle attributes into the fractal/cell shaders. but when it comes down to it that extra detail is always lost with the volume shader, it just always gets flattened or blurry. so i compensate by lowering the cell size and increasing memory but it gets way too slow without much return in detail.

i wonder what 3delight has for volumetrics in softimage now.

steven

[Schoenberger]

More noise examples attached. It was actually a look dev for clouds.

It is a poly mesh with fractal and or cell shader.

 

 

Holger Schönberger
technical director
The day has 24 hours, if that does not suffice, I will take the night

 

 

 

---

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Vincent Fortin
Sent: Saturday, February 19, 2011 6:10 AM

[Schoenberger]

 

One issue if you use particles is that you can have a problem with overlapping of multiple particles.

If you mix two particles with a fine edge structure, then it gets blurry.

 

So you definitely need big particles (set the emission shape to sphere, make the alpha 0.85 for better viewport visualisation)

 

If your particles do not move, then to get rid of the "mixing particles with different noise":

I recommend that you add the noise AFTER the particle_density.

Get a multi math node.

Plug in the particle density as base, a cell as second (subtract) and then a fractal as third (subtract).

 

 

> the addition of a voxel framework in it would potentially blow the competition away

The volume shader is a kind of voxel shader.

 

> notice the almost displaced look of the density... http://magnuswrenninge.com/volumetricmethods

About the volumetrics siggrpah course 2010, most of the stuff is possible with the volume shader.

One thing missing is direct fluid conenction (That will perhaps come in a month).

And a better memory manegement for finer detail  (at the cost of render speed, will be implemented in v4.0 in half a year).

 

But for example the flow fields (Rhythm & Hues). You can already distort the volume in SI to get fluid-like edge noise.

Only issue is that they have an inhouse-tool to apply real fluid motion. But for non-fast-moving clouds you can apply a simple fractal:

This is for example a round displacement with a perlin noise:

http://www.binaryalchemy.de/develop/shd_vol/img/Cloud__Distort__Cigarette_smoke_particles_combined.jpg

But you can also apply other noise displacement for a more cloudy look.

 

 

The issue is not the shader, the issue is how to texture it. How to apply the right noise.

It is not easy/possible to create simple presets (there are two in the particle_shaper),

as the overall look changes with the particle sim (particles large<>small, many<>less, movement)

 

 

From the houdini video, I would say only the first one is not that easy.

Because of the large view and you have to somehow model the shape.

Same issue as my examples: To noisy edges to be real clouds. And the edge is not a round fluid style.

Main point: the clouds do not move. If they do not move, then your lighting can not flicker. Very Very big advantage.

 

I think I have to create some examples right now...

I will not model clouds with polygons (which would be way easier) as most of you do not have the BA_meshdistance shader.

I will try to model some clouds with particles.

 

 

Holger Schönberger
technical director
The day has 24 hours, if that does not suffice, I will take the night

 

 

 

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Steven Caron

Sent: Saturday, February 19, 2011 6:42 AM