I'm spawning particles only at the first $SF and I'd like to control when they begin incrementing age, preferably by when they're added to a group does that make sense? Any tips?

Greetings.
You can use SOP solver in order to control age attribute for each individual particle dynamically during the sim.

Great tip, digging into that. If anyone has an example that would be much preesh!

Ok looks like I've got something working. Many thanks to Francisco Rodriguez for the idea of using pop groups and wrangles to trigger an active state and an active frame in the initial .hip file he posted. All I've done is add another pop wrangle that checks for the active state, if on it sets the current age based on the current frame minus the frame it became active, basically starting the age counter from the time a particle is added to the group.

This is something I'll use all the time so I'm enclosing the .hip file in case anyone else finds it helpful. I'm very new to VEX so any comments or improvements from the experts out there would be great.

This is a small modification to the file to make it even more simple, but not simpler!

Cheers!

VEX so fresh and so clean clean, thanks for the edits!

to not overcomplicate things, you need just 1 line of code

POP Wrangle acting only on in_sphere group

then 2 adjustments:
1. source Jitter Born Time set to None, so that age starts as 0
2. popsolver uncheck Age Particles, since now you are doing it yourself

tamte
to not overcomplicate things, you need just 1 line of code

POP Wrangle acting only on in_sphere group

@age += @TimeInc;

then 2 adjustments:
1. source Jitter Born Time set to None, so that age starts as 0
2. popsolver uncheck Age Particles, since now you are doing it yourself

Ohhh That's not fair Tomas!!

Cheers!!