[SOLVED] Whitewater only on surface, but not below water surface

[sant0s81]

Good morning,

I am trying to implement a fish into real footage.
The animated fish only shows the fin for some frames over the water surface.

I already simulated the water (flip tank).

Now, when I add Whitewater, it appears also below the water surface what looks kinda strange.
What parameter do I have to change, to see whitewater only when the fin goes out of the water?

And how to I get way more whitewater when the fin gets out of the water?

Thank you!

sant0s
 

Edited November 28, 2019 by sant0s81

[JFWfilms]

Hi,

Assuming you're using Houdini 17 or higher. The particles are assigned a different state based on their depth, any particles under the surface will be bubbles, on the surface is foam, and above is spray. If you go into the whitewater solver and turn up the age rate of the bubbles to something like 10,000,000 this will make the bubbles more likely to die, eliminating any particles under the surface. As for whitewater amount you can play around with the settings in the 'Whitewatersource' node under curvature, acceleration, and vorticity. Also up the emission amount in the whitewater solver node under the emission tab.

Hope this helps

Josh

[jimeng20]

And also you could kill all the particles inside of the ocean sdf. If you use a geowrangle and first input is self, second input is the sdf, you can do something like:

 

float sdf = volumesample(1,"surface",@P);

if(sdf < 0){
            removepoint(0,@ptnum)
            }

But this is a hard condition that kill all the particles inside the sdf in the sim, you could also fit the sdf value into a pscale after the whitewater sim.

Something like:

float sdf = volumesample(1,"surface",@P);
float mult = fit(sdf,-0.1, 0, 0, 1);

f@pscale *= mult;

 

Hope this could help.

 

[sant0s81]

Hey @JFWfilms and @jimeng20,

than you for helping, that helped!