Wake Up a Deleted Pop!

POPs
1

So good to play with Pops Thx !
I want draw Pops, so i create the classic technique with the feedback, at the end of their life i Pop delete them.
How i can undelete or wake up the pop One by One ?
i dont want create other i want reuse the same pop used. (0/100)
TouchDesigner_wosX0Mg5E5
Thx for the cues !

2

Hi Fred,

If I understand correctly, you mean you want to reuse deleted points in the feedback loop?

So there is no mechanism for that currently, a couple ways to work around it:

  • not delete the points right away, but delete them outside of the feedback loop (with a condition on their life to either reuse them in the loop on delete them outside the loop)
  • there’s also a toggle on the feedback POP “use memory limit” so if “on” and you create and merge new points in the feedback loop it won’t allocate more memory that what you had pre-feedback at the start of the feedback loop, so you can pre-allocate in a way.

We’re planning on making this easier, with a dedicated feedback loop for particle systems, and also in the future allow more control on memory allocation.

Also if that’s not the case we should add more doc on the concept of “indirect” POPs :
In a few words, for some POPs like the delete POP, the resulting amount of geometry (how many points/triangles… ) is only known on the GPU, except reading it back which is an expensive operation, so all POPs downstream allocate the max/last known amount of geometry.

“Indirect” lingo comes from the fact that for these POPs the compute shaders dispatches are “indirect” meaning the amount of threads to launch is read from the GPU directly

3

Have you looked at the examples of Peter Sistrom and Roy/Tim re feedback loops and particles?

4

Yeah Thank you Vince i figure it out !
Yes Greg i have looked at the crazy exemples, so good inspirations.

Finally it works.
i just merge a point generator inside the feedback Pop loop, i even keep my Pop delete inside the loop, and it reuse the points. it increment and keep the maximum number of Pop i had create. So now i undertood the Use memory limit of the Feedback .
Yeah Pop Style