POP Questions

[catchyid]

Hi,

I am looking at POP Fireworks node and I am not sure how it works, particularly the meaning of merge, split, how streams work. Please see attached image, it has 4 questions. 

Thanks

[anim]

sorry, just very quick reply with some pointers, but I advise you to watch Jeff's masterclass:https://www.sidefx.com/tutorials/h13-masterclass-particles/

- DOP graphs are not like SOPs, they don't pass geometry directly, rather all POPs are solvers, just instructions of what to do to geometry data

- merge DOP is not merging geometry, just making sure all connected (merged) streams are executed

- then notice the dashed line going to trails and starburst, it is supposed to be the indicator that the input stream particles are used as a template to create new particles, so that streams trails and starburst just create and affect those particles, so you still need to merge it with original to get that executed as well (dashed line is not so necessary, as it really depends on what the operator is doing inside, but in case of point replicate POP it works this way)

- streams are just visual representation of stream groups, so overall all particles are part of one geometry per dop object, but every stream just acts on part of them, then after merge all operators affect all merged streams (groups)

- build_your_own_stream can create stream on the subset of the geo as well, depending on the rule vexpression, so the left stream of merge3 can still hold operators that affect all particles and probably that's why it's there, to hint you how to extend the setup a bit

[catchyid]

Hi Tomas, I really really appreciate your help  I am watching the video you've shared and it's very informative. Will read your comments after, then look again at the fireworks example and hope things will be clear then...

Once more, thanks for your help :