Re: One step away from turning Particle Playground into RG's Particular. Ok, sorta...

If what you want to do is to create particles that are smaller/bigger than what was created previously then a Full-on white Property Mapper is what you need. Ensure that this Property Mapper is pre-comped and is larger than the final comp's rez (this last step prevents strange happenings along the edges of the Final Comp.

Once you have the Property Mapper in place and set it to affect Scale, keyframe the max value up/down to suit your needs. You'll likely have to finesse the values with more than 2 keyframes - depending on how you're flying through the particle space.

You should note that any change within the Property Mapper affects new as well as old particles. Hopefully, your fly-through routine doesn't make this obvious, in a bad way.

If you want to control the particle sizes for both old and new particles, then the Layer Map property will provide a more robust solution but it'll require that you animate your particle size correctly as well as the values for Older/Younger & Age Feather properties.

HTH
RoRK

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