"Spawn Emitter at Location" vanishes after a duration

Development Rendering
, , , , ,
1

I am having an issue closely related to THIS answers thread.

I have an actor that when overlapping a volume spawns an emitter and sets its location on tick to follow an animation. When the actor leaves the volume, the location is no longer updated so the emitter no longer moves. Think of this as a drawing where a pen contacts the paper to draw and stops as its lifted up. Every time I drop down to the paper I’m creating a new ribbon emitter until i leave the volume. This works great! Until about 60 seconds in when everything but the currently active emitter vanishes. This cycle continues every 60 seconds. If i speed up my animation I can get through without anything disappearing but its not the desired timing.

Since the ribbon is generated using spawn per unit, my particle counts and total number of emitters is the same if played slow or fast, so it’s not a limitation of either of those.

I’ve also tried spawning the emitters in an actor blueprint and level blueprint but the results are the same. In the previously mentioned answers thread there was talk of garbage collection that the engine runs. Could this be the issue? If so how do I adjust those parameters, or can I even?

Also, I tried using the test project provided in the other answers thread, The emitters disappear in that project as well. I even used the existing particles. I made a slight change to the blueprint to continue the spawning of emitters once every second. Once you get to 60 seconds all but the first emitter vanish. I even made it spawn once every 0.5 seconds and even with double the count they still vanish after this ethereal 60 second limit.

Thanks in advance!

2

Hi dragonfly1 -

Can you take a look at the attached sample project from 4.7.6 and see if you can identify the differences between your setup which is causing the 60 sec duration and the one in the sample project? Just PIE on opening the project and you can see a particle system spawning in at location with a Game Clock running in the logs.

Thank You

Ketchum

Test Project_4.7.6

3

Hey ,

Thanks for getting back to me. The difference is that I’m spawning i decent amount of emitters constantly. Between 1-3 per second. One emitter doesn’t disappear but when there’s a bunch of emitters it dumps them at 60 seconds. Even when there are plenty of resources.

4

53589-spawnemitterbp_test1.jpg
53589-spawnemitterbp_test1.jpg2385×984 369 KB

Here is my BP changes to your project to spawn an emitter grid. When the seconds on screen reach 60 ish you’ll see them vanish. I also disabled the GPU particle emitter in the particle system for testing.

5

Hi dragonfly1 -

This issue was resolved and corrected in the 4.8 version of the editor.

Thank You

Ketchum

6

Nice! I tested it and it works in 4.8.

However my project restricts me to 4.7.6. What was the fix? Can we implement it on our end?

Thanks again for your help!

7

Hello -

Assuming you are not on the Binary but a compiled Engine, you can use GitHub to find and implement the changelist(s) for the fix. You will probably need to setup a separate test project for regression testing to determine the exact changelist.

Thank You

Ketchum