spherical droplets

[3dartvision]

Is there a setting which adds some random noise to the large, currently perfectly spherical, mesh droplets seen as splashes here in my simulation ?

[georgi.zhekov]

Hey,

In Phoenix the liquid particles are rendered as mesh while the foam, mist and splashes are separate particle systems and their rendering is controlled by a Particle Shader.
The Particle Shader has a few modes bubbles/cellular, splashes, points and fog. And these define how your splashes will be rendered.

You can find more about the foam and splashes here - https://docs.chaosgroup.com/pages/vi...ageId=47536229
And on the splash page here - https://docs.chaosgroup.com/display/...plash+%7C+Mist

And here we have some info on the life cycle of the particles - https://docs.chaosgroup.com/display/...les+Life+Cycle

More info on the Particle Shader options can be found here - https://docs.chaosgroup.com/display/...er+%7C+PHXFoam

In your scene your grid resolution is quite low and this is why the splash particles are rendering so big.

If you increase your grid resolution and run the simulation again, the liquid will react much better to the ship shape and your splash particles will be smaller.
I would suggest also to check our ship tutorial here - https://docs.chaosgroup.com/display/...p+in+the+Ocean

Cheers!

[3dartvision]

Hey,

In Phoenix the liquid particles are rendered as mesh while the foam, mist and splashes are separate particle systems and their rendering is controlled by a Particle Shader.
The Particle Shader has a few modes bubbles/cellular, splashes, points and fog. And these define how your splashes will be rendered.

You can find more about the foam and splashes here - https://docs.chaosgroup.com/pages/vi...ageId=47536229
And on the splash page here - https://docs.chaosgroup.com/display/...plash+%7C+Mist

And here we have some info on the life cycle of the particles - https://docs.chaosgroup.com/display/...les+Life+Cycle

More info on the Particle Shader options can be found here - https://docs.chaosgroup.com/display/...er+%7C+PHXFoam

In your scene your grid resolution is quite low and this is why the splash particles are rendering so big.

If you increase your grid resolution and run the simulation again, the liquid will react much better to the ship shape and your splash particles will be smaller.
I would suggest also to check our ship tutorial here - https://docs.chaosgroup.com/display/...p+in+the+Ocean

Cheers!

This is really helpful. Thanks

[3dartvision]

So i'm not sure i fully understand the particle age parameters. i wonder if you might be able to help ?
so as i understand it ... to make a splash reduce in size to nothing over a time period i first enable the PA switch in the particle systems rollout to allow individual particles to dissappear over time from their birth. Then i add a value next to this in the size multiplier. This value represents the number of frames it takes the particle to reduce from 1 to 0. So if i add a value of 25, each splash particle will reduce and fully dissappear over 25 frames of animation.
To control the actual size of the particle i go to 'size addend' and add a value in here which is a physical measurement (+ or -). The 'size variation' value adds randomness to the sizes however its not clear to me how much to add in here as it is not a percentage value.

could you guide me where i might have got this right or wrong please ?

[georgi.zhekov]

Ah I think you confused this a bit.

If you wish to scale down the particles from the Particle Shader you need to keyframe the Size multiplier to go from 1 (or any other value you like) to 0. So let's say that you wish to scale down the particles from 1 to 0 in 1 second - you will need to add a keyframe for the Size multiplier to be 1 at frame 0 and a keyframe with a value of 0 at frame 30 (by default Max uses 30fps). This will scale down the particles regardless of their age.

Then if you turn on the PA button - Phoenix will use the age of the particles and will use the keyframes over the age of the particles. This way when a particle is born it will have a size of 1 and after 30 frames it will be scaled to 0.

If both Size Multiplier and Size Addend are used, the Size Multiplier scales the sizes first, and then the Size Addend is added. This means that even if you scale the particles to 0 with the size multiplier the Size addend will make them big again if you use a positive value. So if you wish the particles to be scaled to zero leave the Size Addend at 0.

[3dartvision]

Ah I think you confused this a bit.

If you wish to scale down the particles from the Particle Shader you need to keyframe the Size multiplier to go from 1 (or any other value you like) to 0. So let's say that you wish to scale down the particles from 1 to 0 in 1 second - you will need to add a keyframe for the Size multiplier to be 1 at frame 0 and a keyframe with a value of 0 at frame 30 (by default Max uses 30fps). This will scale down the particles regardless of their age.

Then if you turn on the PA button - Phoenix will use the age of the particles and will use the keyframes over the age of the particles. This way when a particle is born it will have a size of 1 and after 30 frames it will be scaled to 0.

If both Size Multiplier and Size Addend are used, the Size Multiplier scales the sizes first, and then the Size Addend is added. This means that even if you scale the particles to 0 with the size multiplier the Size addend will make them big again if you use a positive value. So if you wish the particles to be scaled to zero leave the Size Addend at 0.

Ah .. ok, so i only have to put in the two key frames along the time line (one at frame '0' and another at '30') and select the PA button. Then all particles will be affected and reduce down to 0 after 30 frames regardless of when along the time line they are born ?
does that also follow when my timeline begins at -100 frames ?
The other thing which confuses me is the size multiplier values, How do i know what the physical size of the splash particle is that these values are multiplying against ?

[georgi.zhekov]

When the PA button is OFF the particles will be scaled to 0 after 30 frames no matter their age. If the PA is ON, the particles will be scaled to 0, 30 frames after they are born.

If your timeline begins at -100 and you want to use the PA button to scale the particles by age your keyframes need to start from frame 0.

[3dartvision]

When the PA button is OFF the particles will be scaled to 0 after 30 frames no matter their age. If the PA is ON, the particles will be scaled to 0, 30 frames after they are born.

If your timeline begins at -100 and you want to use the PA button to scale the particles by age your keyframes need to start from frame 0.

Thanks for all your help on this. There are a lot of variables and i find it quite tricky to get my around. I really appreciate it.