Whitewater spray- pop replicate on velocity

[mentalgutiar]

Hey guys, 
Im having trouble using the popreplicate on an extra whitewater spray cache. I want to replicate based on v but It will not generate any points even if I crank it. The particles are cached and I have all the attributes in there including velocity but still cannot get it to replicate any particles based on their velocity?

 

Cheers

[markinglevfx]

Something like the file attached?

You can do 'emit from attribute' in the point replicate. So all you would need is to define a 0 to 1 float attribute to drive that dop. I called that attribute 'birth_chance'.

Your speed would be calculated by taking the length of you velocity vector:

length(@v)

 And you can refit that speed value to isolate the faster points for replication:

f@birth_chance = fit(@speed, 1, 6, 0, 1)

You can also multiply this by a refit of the spray attribute to narrow it down further to just spray particles within a certain threshold.

f@birth_chance = fit(@speed, 1, 6, 0, 1)
            *
            fit(@spray, .3, .5, 0, 1);

I also isolated these new replicated spray particles in a pop group, so that they can be ignored by the pop replicate - otherwise you have cloned points creating cloned points which gets messy quick.

 

If you need additional help, upload your .hip workfile so we can get a better sense of how you're working

flip_whitewater_from_v.hipnc

[mentalgutiar]

Oh I see, thank you!

I should have specified before im looking not to resim my particles so am trying to replicate these after my whitewater cache in SOPs?

 

Thanks!