Good! Any details about mesh size, type (probably mesh2), integration
algorithms, etc ?

--
Apache
POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
Email: apa### [at] yahoocom
ICQ: 146690431

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This URL's been mentioned before, but there is this ex-weightlifter that did
some very impressing things: http://graphics.stanford.edu/~fedkiw/

Unfortunately his fluids seem to be in vacuum environments instead of
air/gas, that's why there are no bubbles in the glass of water.

--
Apache
POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
Email: apa### [at] yahoocom
ICQ: 146690431

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> Apache" <apa### [at] yahoocom> wrote in message
news:3cf25f07$1@news.povray.org...
> This URL's been mentioned before, but there is this ex-weightlifter that
did
> some very impressing things: http://graphics.stanford.edu/~fedkiw/

Hi Apache, I loved those animations... I didn't know that page. Impressive!

> Unfortunately his fluids seem to be in vacuum environments instead of
> air/gas, that's why there are no bubbles in the glass of water.

I skimmed through one of his papers, and it seems he DOES take into account
the interaction with air. But I may be wrong... However, the model may not
be THAT realistic or maybe it is too coarse to allow the inclusion of
bubbles in its water.

Fernando.

> --
> Apache
> POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
> Email: apa### [at] yahoocom
> ICQ: 146690431
>
>

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Hug,

You are right, the cloth is a mesh2 object, made of 36*36 points.
Description include normal and uv_map.

The simulation is made by and external program I wrote, which generate an
include file for each steps. It tooks about 30mn to simulate 1000 steps.

For rendering I used Pov 3.5, with a texture:

#declare Pigment_IM = pigment{

image_map {

tga "acp.tga"

interpolate 2

}

}

#declare Pigment_CL = pigment{

color rgbt <1,1,1,3>

}


#declare ClothTexture = texture {

pigment {

average

pigment_map {

[10.0 Pigment_IM]

[1.0 Pigment_CL]

}

}

finish {

ambient 0.2

specular 0.6 // shiny

}

}

It took about 9h30mn to render 500 frames (400*300, no AA, default max
trace. And only even frames to speed up rendering and visual effects)

My goal is to use Pov description as input of my program, + specific tag
such as // #Cloth_simu Cloth(.....)

Today the program knows spheres, cylnder, box, torus planes as well as
rotate, translate and scale. but I focus debug on spheres.

I take into acount gravity and air interaction. For the cloth itself I use
elasticity and damping. I do not include yet object reaction (I think that
is the reason why the cloth seems to be glued to the sphere), and there is
not yet cloth/cloth interaction.

The algorithm is very basic step forward, with dots as weight, linked
together by wires (in this case 2 ranks of neighbours that means 1296
vertexs, 14490 wires). the only thing it includes is an adaptative step
calculation, based on maximum strech/contraction of wires allowed between
each steps.

Chaps

"Apache" <apa### [at] yahoocom> wrote in message
news:3cf25e63$1@news.povray.org...
> Good! Any details about mesh size, type (probably mesh2), integration
> algorithms, etc ?
>
> --
> Apache
> POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
> Email: apa### [at] yahoocom
> ICQ: 146690431
>
>

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If you'd use Runge-Kutta algorithm, you'll be able to speed up the
calculations quite a bit. And the cloth will be more stable too: less
jittering movements and less 'cloth explosions'. With RK you can increase
the step size.

--
Apache
POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
Email: apa### [at] yahoocom
ICQ: 146690431

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If he's taking the air into account, how come those bubbles (see
water-in-glass anim) disappearing into nothing? If there are air molecules
(particles?) those bubbles can't disappear like that. But those water and
smoke anims are really cool indeed.

--
Apache
POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
Email: apa### [at] yahoocom
ICQ: 146690431

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dang that's NICE... the image mapping is very realistic to the
deformation.   I'm always a sap for this stuff and always impressed as
hell that you guys do this for fun!  Tres cool!

-peter
-- 
Modeling slave:
"Ballet pour ma fille."
http://www.applesnake.net

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I've read his papers. He doesn't take air into account in
any realistic way. As fas as I've understood the method,
he does use gravity, some particle-interaction of the
water, but doesn't check if there are air-pockets in the
water. In order to do this, he would have to fill the entire
calculation-block with air-particles, which wouldn't
yield in such fast results, and perhaps not even that
good-looking.

Apache wrote:

> If he's taking the air into account, how come those bubbles (see
> water-in-glass anim) disappearing into nothing? If there are air molecules
> (particles?) those bubbles can't disappear like that. But those water and
> smoke anims are really cool indeed.
>
> --
> Apache
> POV-Ray Cloth experiments: http://geitenkaas.dns2go.com/experiments/
> Email: apa### [at] yahoocom
> ICQ: 146690431

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

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wow! You are good.. i like alot..

Felicitation!

-BEn


"chaps" <cha### [at] yahoocom> wrote in message
news:3cf22baf@news.povray.org...
> Sorry for tha french quotation, but I found it funny regarding the energy
I
> spent to produce that animation.
>
> Some months ago I decided to do, as many other ray tracers, cloth
> simulation.
>
> Very soon, I was fighting with cloth unstability. Thanks to the group, I
got
> some tracks to investigate, but I soon become tired to read all this
stuff,
> even more tired to get no results.
>
> After some months playing with other ideas, I had a look this weekend to
> what I have done, and I found a malicious minus which discreetly took the
> place of the correct plus.
>
> Not so good for my ego.
>
> Chaps
>
>
>
>

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