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Point Age/Frame Born in SOPs


GeoGem

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Ive followed Entagma's tutorial to make a the custom snowflake growth solver, everything is working great.  Ive added an ID point attrib to keep a constant point id. 

What I am now trying to do is to create an emitter from the latest points 'created' in the past 3 or so frames.
I fully understand that I can import into a popnet and use all the age/life/birth/jitter options to get the effect im thinking of....
the problem here is that all points from the start of the snowflake growth sim, exists on every frame, which reads into the POPsource, not giving me the effect of NEW points making a trailing emitter.

so ive been trying to do something as simple as using a SOPsolver IN SOPs(not dops/pops), to fade @Cd.r=1 every frame to black, then just using a blast or removepoint in wrangle to delete a threshold of points below a certain chf('threshold').....but i cant get it to act on the newly created points of the snowflake solver....

my second attempt has been: 

int prev = pointattrib(1, 'id', @ptnum, 1);

if(@Frame > 1){
	if (@id == prev){
    @Cd.r=1;
    }
	else{
	@Cd.r=0;
    }
}

[ NOTE: Im using colour to just automatically visualize this before swapping to removepoint or using a blast node w/ threshold ]
So, wiring the stream from the snowflake sim, into a timeshift( $F-1 ), then into opinput1 of my pointwrangle, so i can read the id point attribute from the previous frame, compare it to opinput0, in which....logically in my head, should colour the current frame points to be RED, and the PREV frame points matching CURRENT frame points to be BLACK....
even if this worked, id be slightly lost on how to blend it with the past few/N # of frames....

to dumb my question down to the most basic, im needing to add an manual AGE attrib based on the per point creation frame or even just a time/seconds float.... keep in mind, this is not set up in dops/POPnet as of right now.
im probably missing something fairly simple, unfortunately a search of odforce, cgwiki and sidefx forums havent provided me with a solution.

THANK YOU!

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11 hours ago, Librarian said:

You have Nice ex with files regarding Solver HERE

 

And here

much appreciated, thank you

I ended up figuring out a cheat by using good old AttribTransfer with a timeShift.
Though im not sure of any downsides of doing it this way, id still like to learn how to implement an @age without using dops.
ill look thru the links you shared.

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