Helicopter crash - RnD

[Svetlin.Nikolov]

Ah, yes, it could be that the actual liquud particles are sliding over the surface and creating foam. Is your foam rising speed about an order of magnitude lower than the falling speed? If it's too high, then the foam will jump quickly above the surface and could appear to be floating.

[LarsSonparsson]

In that simulation, it was default 1m rising 10m falling.
For a new sim that is currently running, rising is lowered to 0.5m.

[LarsSonparsson]

Nope, it's still creating that foam edge.

I'll build that scene again, so I can check that everything really is in right scale and there isn't any weird keyframes causing extreme velocities etc.
Btw, I have no hurry with this project. If I have a perfect setup before christmas, that's fine. After that I can start to play with the real model and scene.

[LarsSonparsson]

One more workflow question.

If I first create a sim where liquid and splashes looks good, can I then do resim versions for foam and mist without simulating liquid and splashes again?
Liquid and splashes affects each other, but foam and mist are just generated over that. They don't affect the shape of the simulation. Right?

[Svetlin.Nikolov]

You should be able to keep any particle group, check here how: https://docs.chaosgroup.com/display/...ation-Overview

Indeed, foam and (EDITED:mist) should not affect the liquid and splash.

Cheers!

[joconnell]

The stills are looking awesome Lasse!

[LarsSonparsson]

Black dots. Any idea what those are?
I've again tried many things to fix it, but no luck. Foam is now rendered as geometry bubbles and splashes as geometry splashes.

[georgi.zhekov]

Do you have the "Use Light cache" enabled in the Particle shader? Do the black dots appear only in geometry mode?

[LarsSonparsson]

Light cache is on at value 0.5. Dots appear even if the geometry mode is turned off.
I thought that the Light Cache could give some other kind of problems, not black pixels. I'll try to render it with Light Cache turned off.

[Guest]

Hmm... Same spots but white coloured are caused by the sun If the option Invisible is unchecked. Looks like these white spots have transparency in the alpha channel and because jpg doesn't support alpha makes them black. But this is just a speculation. You can check Invisible option and try rendering again

[LarsSonparsson]

No sun in this scene. Only dome with hdr.
Those black pixels have alpha at 1, so no transparent. After Effect shows rgb value nan, which could mean that there is some negative values, right?

https://www.dropbox.com/s/x9rsqgkijt....0149.exr?dl=1

[georgi.zhekov]

Nan values means there is nothing recorded there.

Can you send us the scene with a single cache file so we can take a look where the problem is?

Thanks,

[LarsSonparsson]

Thanks,
You got mail.

[Guest]

Roger that

[Guest]

Hi,

we have found that the option Render As Geometry in particle shader for splashes is causing these artefacts. Disabling this option will avoid the problem. It's a quick workaround until we fix this issue.