Foam particles to pflow? ...and rendering foam?

[LarsSonparsson]

Is there an option to render foam particles as pflow particles?

Currently foam is rendering really really slowly ...and because I can't assign any actual material to it, I'm not sure what is going wrong.
I just don't understand what is taking so much time. Is it just the forming of the bubbles during the render time or is it the complex shading of them or what?


The setup I'm testing now is really simple. Pouring some coffee to the glass and trying to get some bubbles to form in top surface.
That works actually really well and I get nice formation of bubbles to surface level. Not like a foam in beer, but more like you see in coffee. There is totally 6550 foam particles and I'm rendering only the ones that are above water. So I thought it could be quite easy to render it, but that not the case. No matter what setting I try, the render time is turning to impossible. Without bubbles 1min and with bubbles the render is still going on after 17 minutes of waiting. ???

phoenixFD_adv_21010_max2012_vray_24_x64_23635

[Ivaylo Katev]

could you share some settings and scene details?
the best solution is to send us the scene, and single cache file
6560 particles should be rended in few seconds, actually the fastest foam setup renders 14 millions of particles in less than a minute!

[LarsSonparsson]

There you go.


CoffeeAndBubbles_Frame_19.zip

[Ivaylo Katev]

there is something in the render settings that causes 10 times slower rendering tracing 10 equal rays for each pixel, even with fixed sampler set to 1 ray per pixel
i just switched to scanline and back to vray and the rendering was fixed, but still can't say what is the reason

however, even with fixed rendering, it is still too slow!

[LarsSonparsson]

Hmm... ok.

I'm getting quite okay rendering times at the moment, but without gi or motion blur. Motion blur is totally no go. GI using bf/lc works fine, but with im/lc it just wont render at all.
Maybe I try to recreate that scene from zero and see if that helps. At least I learned how to use foam for the first time.

Thanks again.

[Ivaylo Katev]

for some reason your glass is rendering very slowly, and for the foam i think you will need more particles.

[LarsSonparsson]

Somehow almost all the particles dies really soon... like before frame 19. I might even get 100k particles or more in the beginning, but then they just die and there is only few thousands left.
How could I make them last longer?

[Ivaylo Katev]

this is really strange, your half life is big, no idea why it happens. in some nightlies there was a bug that makes the particles to fly out with big speed, but as i see your bounding box is not bigger than the container.
anyway, try to download latest nightly

[Magnum_design]

Did you come to any conclusion regarding this. If I try to set up a scene with beer and foam with exactly the same settings as the sample scene. ( But didn´t start with that scene ) the render get stuck on the foam. If I render the samplescene it renders flowless...

Btw... I´m wondering how you know how many foam particles you are using ? ? How scale senitive is it ?

[Ivaylo Katev]

you can chest the foam particles in the input panel, it shows the content of the currently shown cache file.
tell us the count of the particles in the scene, or just send us a scene with information which build are you using. the foam birth was modified and we must be sure that our simulation is identical with your

[Magnum_design]

Hm weird. I get 2.8 mil particles ? in the beer scene it´s 28k. ( this is in the middle of the sim )

I need to check everything again. how do I control this ? I started with the same scale?

[Ivaylo Katev]

use the foam birth rate

[Magnum_design]

Yes, I tried that now. 100 times smalle it workes perfect But since I was convinced I was working in the exakt same scale and settings I never wanted to change anything. Must have done something different m the samplscene. Irritating!! haha thanks Ivaylo!!