Fluid shading research

[Schoenberger]

Hi

 

I am doing some research for fluid shading.

I know three widely used fluid systems regarding fluid shading (missing one?):

 - Maya

 - Houdini

 - FumeFx

 

I have to learn all of them, but in the meantime I want to ask if some of you have used them (or know someone who has used them).

I am looking for some features that you think are essential for fluid shading, features you need/would like to have.

 

You can also send me some examples (off list if you prefer).

What could help a lot is if you can send me a cache file of a fluid sim you have done (in one of the above apps or others), together with a rendered image and a description what shader features you have used. And then I would have to try to re-create the look.

 

Just spread your ideas, everything is welcome, cause once the outlines for the shader are started, it is hard to change them.

 

Let the brainstorming begin, thanks,

Holger Schönberger
Binary Alchemy - digital materialization

[Tim Leydecker]

Hey Holger,

http://lesterbanks.com/2011/01/maya-2011-the-basics-of-the-3d-fluid-container/

is a good start for Maya Fluids, http://lesterbanks.com/ in general.

The above takes you through the first steps and might also give
you a workflow hint or two about how to approach the endless
amounts of roll-outs found in Mayas tools (invented by Duncan Brinsmead).

Personally, I found the above tutorial doesn�t lead to understanding
much but a more or less fearless trial&error approach.

If you can choose, I�d suggest you might as well start with fumeFX.

It�s years that I�ve used it myself but I can see why people
fame it for it�s great and easy workflow, especially it�s shading.
Additional use of Thinking particles might be desired, I can�t
comment on the combo.

Cheers

tim

> Holger Sch�nberger

[christian keller]

http://www.cs.cornell.edu/~tedkim/WTURB/

enhancement via wavelet turbulence
maybe a rendering mode which is free of a voxel accel structure
,so that you can purely march the volume - don´t care for memory.

½

christian keller
visual effects|direction

+49 0179 69 36 248
chr...@gmx.de

[Tim Leydecker]

Sorry for the split-spamming, but here�s more:

http://www.thegnomonworkshop.com/store/product/898/Introduction-to-Maya-Fluid-Effects

The results look nice for Maya fluids. I wonder how he does it.
Might be worth to check out how much you could get out of:

http://www.thegnomonworkshop.com/subscription/

Another really great source of samples of FX, smoke, debris, .etc
comes from a blur studios guy, I can�t find the page unfortunately
but maybe Steve Caron could help out with some info on this?

Cheers

tim

[Schoenberger]

 

Wavelet turbulence is in fact a re-simulation that takes time.

And as a simulation, you need to convert frame after frame and cannot be done in a 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 christian keller
Sent: Monday, March 07, 2011 5:09 PM
To: soft...@listproc.autodesk.com
Subject: Re: Fluid shading research

[christian keller]

yep, but why can´t that be done in a shader ?-)

christian keller
visual effects|direction

+49 0179 69 36 248
chr...@gmx.de

[Gene Crucean]

I would personally look into these in reverse order.

- Fume

- Houdini

- Maya

- Another one is http://www.chaosgroup.com/en/2/phoenix.html. But that's a fresh release and from the little I know about it, unproven in production.

IMO, Fume is bar none the one you want to look into the most. It's also the one that most people envy the most. It just does soo many things right. I'll see if I can round up a sim and render for you to play with.

Houdini is also nice but no where near as easy to get the same results as Fume. However, it is quite a bit more flexible.

Maya's fluids drive me nuts.

I might also look into http://opensource.imageworks.com/?p=field3d

This sounds like it's going to be good Holger. I look forward to your testing!

--
[Gene Crucean] - [VFX & CG Supervisor/Generalist]
** Freelance for hire **

[Andi Farhall]

my very basic 2 pence worth.....

 

I've dipped a toe into Fume, i think compared to maya it's much faster to simulate possibly because there isn't anywhere near as much to tweak as in maya,  which is good for me as there's less sliders which means quicker results - generally, although i imagine i could get frustrated with a lack of controls in the long run.  One bugbear that i've always stumbled across is voxels being clearly visible when trying to do refined flames. Ideally i want the edge of the flame to be crisp(ish) but this gets softened when trying to hide those edgy voxels.

 

 

this is an example of the sort of stuff i've been up to

 

http://dl.dropbox.com/u/11492490/ZIpTesting_J.mov

 

A.

[Dan Yargici]

I know I keep banging on about it but I really like the way Blender's smoke renders....

I wish I could tell you the shading model it use etc. etc. but I have no idea!  However with it being open-source I'm sure it wouldn't be too hard to discover.

http://www.vimeo.com/9240074

http://www.vimeo.com/9907058

http://www.vimeo.com/7356113

DAN

[Schoenberger]

A shader can only access one frame. And you donot know which one.

Batch rendering frame 10, frame 50, frame 1....

A simulation has to be done frame after frame.

 

 

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 christian keller

Sent: Monday, March 07, 2011 5:18 PM

[Schoenberger]

@Dan:

> However with it being open-source I'm sure it wouldn't be too hard to discover.

As long as I do not look at the source I can take a look at blender. Copyright issues...

@Andi Farhall:
Do you have one/two chache files of the sim you can share? Then I can try to render it the same way in SI.
http://www.digidragon.de/upload.php

 

@Tim:
>http://www.thegnomonworkshop.com/store/product/898/Introduction-to-Maya-Fluid-Effects
Hmm, I will check the library of the university. Hopefully a lot of high-end shadings and cache files I can create.

 

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 Dan Yargici
Sent: Monday, March 07, 2011 5:26 PM

To: soft...@listproc.autodesk.com
Subject: Re: Fluid shading research

[christian keller]

ah, never read the paper, i thought it´s an enhancement which can be done by having the
velocity of the cells, and then warping a noise structure ...

christian keller
visual effects|direction

+49 0179 69 36 248
chr...@gmx.de

[Gene Crucean]

I would also look into Blenders fluids. They are quite nice, and FREE.

Grab the latest build from here: http://www.graphicall.org/builds/

[Steven Caron]

http://www.brandonriza.com/3DVisualEffects/HTML/3DVisualEffects.htm

brandon's stuff is almost all fumefx, pflow, and fusion for compositing.

s

ps. i dont work at blur studio any longer

Holger Schönberger

[Steven Caron]

ya, support for field3d would be awesome.

if you support this format then you put the power in the hands of the TD to decide which simulation software to use and remove a lot of excess work in coming up with your own format or supporting any of the listed software directly. as of late last year houdini's SDK has a field3d example, so you take care of houdini users. also i think you might be hard pressed to get anything out of afterworks about their fumefx caching format (.fxd)

then eric mootz and exocortex guys can meet you in the middle by supporting that format, so we can look to softimage for native simulation options.

also remember that pdf i linked in the clouds thread a few weeks ago. nothing in particular about it, just inspiration..

s

On Mon, Mar 7, 2011 at 8:19 AM, Gene Crucean <emailgene...@gmail.com> wrote:

I might also look into http://opensource.imageworks.com/?p=field3d

On Mon, Mar 7, 2011 at 7:43 AM, Schoenberger <X...@digidragon.de> wrote:

Hi

 

I am doing some research for fluid shading.

I know three widely used fluid systems regarding fluid shading (missing one?):

 - Maya

 - Houdini

 - FumeFx

 

I have to learn all of them, but in the meantime I want to ask if some of you have used them (or know someone who has used them).

I am looking for some features that you think are essential for fluid shading, features you need/would like to have.

 

You can also send me some examples (off list if you prefer).

What could help a lot is if you can send me a cache file of a fluid sim you have done (in one of the above apps or others), together with a rendered image and a description what shader features you have used. And then I would have to try to re-create the look.

 

Just spread your ideas, everything is welcome, cause once the outlines for the shader are started, it is hard to change them.

 

Let the brainstorming begin, thanks,

Holger Schönberger
Binary Alchemy - digital materialization

[Schoenberger]

 

I will definately have a loader for that format, but I do not know if I will use that or my own format (already finished with loader/saver) internally.

And my format is compatible with Erics internal format.

The only advantage of using the field3D internally would be to use the sparse grid.

 

As for FumeFX, I heard of a company that has written a loader.

And I do not think that they will implement support for field3D in the next time.

Same for Maya.

Houdini, depends. Afaik the default .bgeo format was not to complicated to read (already have it in my particle loader)

 

 

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: Monday, March 07, 2011 8:01 PM

To: soft...@listproc.autodesk.com
Subject: Re: Fluid shading research

[Carl Callewaert - Fundi3D]

HI

if some of you still have problems exporting Softimage content to Unity let me know what the problems are.
I work now for Unity as their evangelist. During GDC I got to know the team and got to know the fbx import specialist.

Regards;
Carl C

[Steven Caron]

oh ok, thats great.

but i read here houdini has support for field3d through an example in their 'HDK'...  http://goo.gl/xgtme

so i was suggesting that you could support houdini by supporting field3d, and not have to support bgeo.

s

[Eric Turman]

Great! So does this mean that they are seriously interested in helping the Softimage community to get Unity to work better for them?

--




-=T=-

[tak...@earthlink.net]

At least Carl is I think.  :)

-T

-----Original Message-----
From: Eric Turman
Sent: Mar 7, 2011 2:42 PM
To: soft...@listproc.autodesk.com

[jason slabber]

i'd strongly suggest looking at the pyro material/shader in houdini, it has a great amount of control and quite frankly way better than the control you can get with fumeFX.
http://www.sidefx.com/docs/houdini11.0/nodes/shop/pyro
also you easily could dive into the vex and look at the the way it's constructed.

jason

--
.................................
//sim+light+render
  // http://vimeo.com/user3404661/albums // http://vimeo.com/channels/naiad

[Tim Leydecker]

Hey Steve,

thanks for sharing that link, Brandon Riza was indeed whom I meant!

http://www.brandonriza.com/3DVisualEffects/HTML/3DVisualEffects.htm

Cheers

tim

P.S: Have fun with your new job!

>>>> Holger Sch�nberger

[Tim Leydecker]

http://www.sidefx.com/docs/houdini11.0/nodes/shop/pyro

great source/info, jason.

cheers

tim

>>> Holger Sch�nberger

>>> 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:* Monday, March 07, 2011 8:01 PM
>>>
>>> *To:* soft...@listproc.autodesk.com
>>> *Subject:* Re: Fluid shading research

>>>>> Holger Sch�nberger

>>>>> Binary Alchemy - digital materialization
>>>>>
>>>>
>>>>
>>>>
>>>> --

>>>> [Gene Crucean] - [VFX& CG Supervisor/Generalist]

[Schoenberger]

Hmm, after looking into Fume, Houdini, Phoenix and Maya, it alls seems those
shaders are pretty simply.
Thought that there could be a bit more "magic".
Way more easily than a particle shader.

But it seems that they only map a value (temperature, density) via a
gradient to a color.
If you simulatre UVW texture coordinates, you can apply a texture.
Seems to be all...

So that would be what I will do. But split into small nodes that you have
full control.
[Get Value (temperature)] -> [XSI gradient] -> [color input of fluid
shader] -> [volume]
[Get Value (density)] -> [XSI gradient] -> [density input of fluid shader]
-> [volume]

Holger Sch�nberger
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 Tim Leydecker
|> Sent: Tuesday, March 08, 2011 11:08 AM
|> To: soft...@listproc.autodesk.com
|> Subject: Re: Fluid shading research
|>

[Morten Bartholdy]

Holger I can hardly wait. It is the only thing required to make Maya
(almost) obsolete here.

/MB

> Hmm, after looking into Fume, Houdini, Phoenix and Maya, it alls seems
> those
> shaders are pretty simply.
> Thought that there could be a bit more "magic".
> Way more easily than a particle shader.
>
>
> But it seems that they only map a value (temperature, density) via a
> gradient to a color.
> If you simulatre UVW texture coordinates, you can apply a texture.
> Seems to be all...
>
> So that would be what I will do. But split into small nodes that you have
> full control.
> [Get Value (temperature)] -> [XSI gradient] -> [color input of fluid
> shader] -> [volume]
> [Get Value (density)] -> [XSI gradient] -> [density input of fluid
> shader]
> -> [volume]
>
>
>

> Holger Schönberger

> |> >>>> Let the brainstorming begin, thanks, Holger Schönberger Binary
> |> >>>> Alchemy - digital materialization
> |> >>>>
> |> >>>>
> |> >>>
> |> >
>
>
>

--
Best Regards

Morten Bartholdy
3D/VFX Supervisor

[Piotrek Marczak]

Yes this is so simple that we have tons of those shaders available for
softimage ;)
W dniu 2011-03-10 12:00, Morten Bartholdy pisze:

[Schoenberger]

PS: Seems that the first alpha version will support the next emfluid4 and
Maya.
Perhaps Phoenix, they told me they have a pretty complex compression.

Holger Sch�nberger

|> > Holger Sch�nberger

|> > |> >>>> Let the brainstorming begin, thanks, Holger Sch�nberger

[Robert Chapman]

Hi Holger,

sounds great! wish we could have had this sooner if it was so easy :)   I'd like to ask about Light absorbtion / Emmission & Scattering, would there be a setting for number of bounces - is that the right terminology for Scattering?  also would we have an ability to precompute density, temperature and illumination info to a cache to be read by the shader?

regards,

Rob

On 10 March 2011 10:56, Schoenberger <X...@digidragon.de> wrote:

Hmm, after looking into Fume, Houdini, Phoenix and Maya, it alls seems those
shaders are pretty simply.
Thought that there could be a bit more "magic".
Way more easily than a particle shader.


But it seems that they only map a value (temperature, density) via a
gradient to a color.
If you simulatre UVW texture coordinates, you can apply a texture.
Seems to be all...

So that would be what I will do. But split into small nodes that you have
full control.
[Get Value (temperature)]  ->  [XSI gradient] -> [color input of fluid
shader]  -> [volume]
[Get Value (density)]  ->  [XSI gradient] -> [density input of fluid shader]
-> [volume]

Holger Schönberger

 |> >>>> Let the brainstorming begin, thanks, Holger Schönberger Binary
 |> >>>> Alchemy - digital materialization
 |> >>>>
 |> >>>>
 |> >>>
 |> >

[Rob Wuijster]

shhh... don't spook him ;-)

Rob

\/-------------\/----------------\/

-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1204 / Virus Database: 1497/3495 - Release Date: 03/09/11

[Schoenberger]

@Piotrek

|> Yes this is so simple that we have tons of those shaders
|> available for softimage ;

:-)

Getting the data into the render tree is the complex thing as you have to
write a geometry shader.
(But I was able to copy my particle cache loader and had "surprisingly" the
same data format as emFluid4).
But to be true, if I would have thought that it is that easy I would have
started earlier.
No problems, just working straight away.
Took me one,two days to get fluids rendered in Softimage.
Now one-two days to optimize it (that is the harder stuff) and do the UI
stuff.
And then I try to get at least something magic into the shader.
Hmm, perhaps I will release a first version today without any magic.

@Robert

|> I'd like to ask about Light absorbtion / Emmission & Scattering, would
there be

|> setting for number of bounces - is that the right terminology for
Scattering?

The volume shader is the same. (That's also why it did not took that long)
The fluid shader is just a replacement for the particle_density shader.
More than one bounce is usally not visible in a cloud.
Improvements to the volume shader will take months.

|> also would we have an ability to precompute density,
|> temperature and illumination info to a cache to be read by the shader?

The shader can read cache files.
For now Maya and an own format (C++ SDK on request, if someone likes to
create pythin script, would be nice, it is just a float array, written with
gzip compression)

Holger Sch�nberger

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 Piotrek Marczak
|> Sent: Thursday, March 10, 2011 12:03 PM
|> To: soft...@listproc.autodesk.com
|> Subject: Re: Fluid shading research
|>

|> >> Holger Sch�nberger

|> Sch�nberger Binary
|> >> |> >>>> Alchemy - digital materialization
|> >> |> >>>>
|> >> |> >>>>
|> >> |> >>>
|> >> |> >
|> >>
|> >>
|> >>
|> >
|>

[Piotrek Marczak]

That's really cool!
All I dream of is fumefx quality and fair price :)

http://vimeo.com/19315395
or any blur cinematics

W dniu 2011-03-10 12:23, Schoenberger pisze:

> @Piotrek
> |> Yes this is so simple that we have tons of those shaders
> |> available for softimage ;
> :-)
>
> Getting the data into the render tree is the complex thing as you have to
> write a geometry shader.
> (But I was able to copy my particle cache loader and had "surprisingly" the
> same data format as emFluid4).
> But to be true, if I would have thought that it is that easy I would have
> started earlier.
> No problems, just working straight away.
> Took me one,two days to get fluids rendered in Softimage.
> Now one-two days to optimize it (that is the harder stuff) and do the UI
> stuff.
> And then I try to get at least something magic into the shader.
> Hmm, perhaps I will release a first version today without any magic.
>
>
> @Robert

> |> I'd like to ask about Light absorbtion / Emmission& Scattering, would

[Schoenberger]

|> All I dream of is fumefx quality and fair price :)

As I said, the most work/magic is done in the fluid simulator, not the
shader.
At first, no price at all for the alpha (some months).

[Sandy Sutherland]

Mmm not so sure I agree - trying to do smoke and dust right now - and
the rendering/shading side is pretty tricky to get right!!!

S.

[jason slabber]

thats because you supposed to be rigging!

On Thu, Mar 10, 2011 at 1:59 PM, Sandy Sutherland <sa...@triggerfish.co.za> wrote:

Mmm not so sure I agree - trying to do smoke and dust right now  - and the rendering/shading side is pretty tricky to get right!!!

S.

On 3/10/2011 1:38 PM, Schoenberger wrote:

 |>  All I dream of is fumefx quality and fair price :)
As I said, the most work/magic is done in the fluid simulator, not the
shader.
At first, no price at all for the alpha (some months).

Holger Schönberger

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

[adrian wyer]

Served!

 

Adrian Wyer
Fluid Pictures
75-77 Margaret St.
London
W1W 8SY
++44(0) 207 850 0829
adria...@fluid-pictures.com
www.fluid-pictures.com

 

Fluid Pictures Limited is registered in England and Wales.
Company number:5657815
VAT number: 872 6893 71

---

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of jason slabber
Sent: 10 March 2011 12:54
To: soft...@listproc.autodesk.com
Subject: Re: Fluid shading research

 

thats because you supposed to be rigging!

[Schoenberger]

> Mmm not so sure I agree - trying to do smoke and dust right now

> and the rendering/shading side is pretty tricky to get right!!!

Which simulator do you use (Maya, Fume, Phoenix, Houdini)?
And with which parameters do you fight?

Holger Schoenberger

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

[Sandy Sutherland]

Multi Tasking dude - multi tasking............................................  :-P

S.

[jason slabber]

lol, yeah...