Active Bodies - How can i link a highres Mesh to a clone?

[georgi.zhekov]

Ah, the form won't let you attach file, but if you scroll down a bit the mail is there as well

[olika]

Will upload the scene next, in the meantime here's a motion sample.
Also noticed another strange thing with the foam.
As you can see it's kind of falling down like raindrops? Looks like falling from 10-20 cm height to the water surface.
Any clue what could cause this? Will it be fine in in the render bercause of the displace etc?

[olika]

georgi.zhekov
Here's the scene, i also uploaded it via mail.
https://we.tl/t-tPNJbx4oRo

[georgi.zhekov]

Check the foam size and the falling speed of the bubbles. It could be the bubbles are way too big.

[olika]

Ah ok, thx! I wasn't aware that the whole size parameter set does influence the foam behavior even when i'm not using bubble mode to render later on.
But that makes sense!

Do we have a questionaire friday?! Thanks for your support georgi.zhekov
May i also take my chance and ask what influence the B2B Interaction has in such a ocean setup?

[olika]

Ahuumm, seems i have general unit issue in that scene.
It is set up with Meters as shown units and 10 cm as internal units (guess i seen it in some tutorial to do it like this...)
When i rebuild the scene with both cm and cm then everything is working as it should.
Foam is behaving properly and the Volume Birth Control is working and there are no more particles created at the borders.

As it is quite a big object i thought it is a good idea to change the units to something bigger but now i'm unsure. What is the benefit of changing units and what else do you have to change accordingly. When i take a look at the active body Boat scene, there is both set up with Meters, Meters. But when i build the scene in Meters, the simulation is totally off. I.e. there are puffs of particle shooting out of the water surface etc.

[georgi.zhekov]

Your scene wasn't working because you had the object used as a birth volume in the Exclude list in the Scene interaction rollout.

As for the scale of the scene you can take a look at this page here - https://docs.chaosgroup.com/display/PHX4MAX/Liquid+Grid

In short - the way you view the units in Max is irrelevant. Phoenix always converts the units to a common world-size length, so the only important thing is the size of the container.

Cheers!

[olika]

georgi.zhekov ! That is the killer tip! priceless! Not in a hundred years i would have thought of!
Thank you so much! Big milestone haha have a nice weekend! well deserved from my side! Greetz to the chaos crew!

[olika]

Wish you all a good start into the week folks!
I spend my weekend simming simming simming aand simming
But it was worth it! The system is actually up and running and it's working yeay
Still learning a lot about splash and foam thresholds and the results are improving bit by bit.
Here's the first rendered snippet of the corkline, working on two-way interaction with tyflow with a lot of debris and actually a stable floating active body boat! double yeah, It's looking good so far.
Subscribe i'f your're interested i will try my best to keep you updated.

Sorry for the crappy gif's, but there''s no direct upload of video files in here, right? Too lazy to upload it first to youtube or vimeo

[olika]

I still dabble a little bit with an unwanted sideeffect, i do not know what could causing it.
When splashes gets created, some shoot downwards quite speedful some distance and creating a little foam trail which then raises.
At first i thought that the splash threshold was so low that underwater velocity caused it, but even when i raise it about over ten, there is still those downward shooting splashes?
If you take a close look to the gif you can also see them coming up on the front of the bouys.
Any suggestion to that? Thanks in advance



Edit: Seems like increasing the sim steps up to two gets rid of like 80% of those high velocity splashes but i'm still wondering what is causing it.
As it happens with tyflow physxfluid on the left ( yellow debris) and the active force boat hull back on the right.
Maybe there are any specialties to this because it's all so new?

[Svetlin.Nikolov]

Hmmm, are you 100% sure this is Splash and not Foam? Asking cause by default the Foam preview color is green.

If it is Foam indeed, then maybe the falling speed is too high and particles slightly above the surface get accelerated quickly and dive underwater...

[olika]

Hi Svetlin.Nikolov ,
thanks for reply. Jep it's just a few splash particles going off with high velocity down. Sorry, have my own color, splash red, foam green.
So the foam is just generated by that single high velocity particle. Turning down falling speed seems to not influence it at all.
Right now, no matter what i try, i only can get rid of with two substeps. Bit of a suspect that maybe the active body is pushing extraordinary. Did you have turn on foam and splash in the active boat example? I will try.

[Svetlin.Nikolov]

Interesting, so in this case do you have Foam on Hit enable for the Splash settings? If so, would it help if you disable it?

[olika]

Jup, only Foam by splash, will do a sim without foa at all.
I'm stuck in units again... Just a question as i'm playing with it right now.
What is the benefit of increasing the Scene Scale parameter beside correcting your incorect scene size as described in the docs.
I mean, when i place my boat into a new max scene and then hit the ocean preset button, the preset ends up with the boat with a scene scale of 3,345?
So boat is in correct size, sim container is too kind of, so why is the preset inceasing the scen scale. What i'm trying to find out right now, does it somehting to dampen forces etc.

[Svetlin.Nikolov]

Oh, all toolbar presets adjust the scene scale so no matter what object you throw at them, they will work roughly the same, in a predictable manner. You wouldn't want to worry about the scene scale for the toolbar preset when you are a rookie, and wouldn't want a large smoke preset for a simulator that is 1cm tall or a tapwater preset for a simulator 1km tall