Formula for adjusting time time scale when scene scale is increased

[tmbarker531]

Hi,

I'm creating a animation of an object dropping into a fish tank and creating a large splash. From the tests I've done, the splashes looks much better when the scene scale is increased to somewhere between 10 or 15, but of course the speed of the splash then feels very unrealistic. Is there some kind of formula for how much I should increase the time scale so that the water splashes and falls at the correct pace?

I've found that when I simulate the scene at a scene scale of 1 I cannot get enough resolution and steps to make the water look realistic in a reasonable amount of simulation time (12 hours for 150 frames, Intel i9 14900k). But maybe I'm underestimating how much processing time I really need to get a good simulation?

Any advice would be much appreciated, I don't use phoenix very often.

[georgi.zhekov]

Hello,

I'm afraid there is no specific formula on how to adjust the time-scale to compensate for the large scene scale.

How about using a combination of changing the scene scale and adjusting the steps per frame?

When creating fish tank splashes there is a very fast movement and when the scene scale is quite small you will need a lot of steps per frame in order to compensate for the fast liquid movement.

Without references and any screenshots or videos of your results it's a bit difficult to guess, but if Scene scale of 10 or 15 looks good motion wise, but way too slow, how about dialing down the Scene Scale to 5 or something, increasing the steps per frame (depends on how many are you using currently - for very vast movement 10-15 or even 20 steps are needed) and then tweaking the Time-Scale. If you lower the Time-Scale below 1 you can lower the Steps per frame as well. If you use a Time-Scale of 1 and 10 steps per frame for example, when changing the Time-Scale to 0.5 you can drop the Steps per frame to 5 and vice versa.

I've found that when I simulate the scene at a scene scale of 1 I cannot get enough resolution and steps to make the water look realistic in a reasonable amount of simulation time (12 hours for 150 frames, Intel i9 14900k). But maybe I'm underestimating how much processing time I really need to get a good simulation?

Can you show us your settings and the results you're getting?

Cheers!