Niagara secondary emitter Spawn count per particle ID or Index from first emitter?

I am currently trying to create particles with links per each particles. I am approaching this by spawning a particles on a sphere, where the particle count is being read by a user integer custom attribute. The custom count is being read from a jason file via blueprint.

Now regarding the links related to the particles. I am spawning a secondary particles for the links based on the first particles. That said I am having Particles A (Nodes) and Particles B (the links). Particles B count per particle need to be set via array custom attribute to set the secondary particle count per particle. I am not clear on how to handle per particle attribute by custom array.

So lets say Particle A ID number 134 has 4 links (Spawned count for particle B), how can I map that attribute via Array Int32 input per particle?

If any article or link that could help on this as well would be super appreciated!
I have found almost no documentation on advanced features of Niagara.
Also I was looking at this video, no project files and no responses on the requests for the files:
Diving Into Niagara: Intelligent Particle Effects | Unreal Fest Online 2020

Please help, thank you.

since you seem to have a fixed number of particles you can spawn X particles in emitter A on the mesh via SpawnBurstInstantaneous module script in emitter update of A. then you do the same in emitter B but with X * 4 if you have 4 links per particle. Then you need to write a scratchpad in B to sample values of particles in emitter A. therefor you use the index. the index you want to access is the ExecutionIndex of B divided by 4 (number of links) then you get the source particle and can read all values from it. you might need to check “Requires Persisten IDs” in the emitter properties of A

hope that helps :slight_smile: