Bug in particle system - collisions randomly stop

Hello,

we are running into following bug, which is best described by a video, so I made one:

What happens here is that we have a particle system, which is combined from two emitters. The second spawns a particle as soon as a particle from system one dies.

As you can see from the video, this works nicely in editor (in runtime simulation mode) and it also works in game. As soon as I press F11 (maximize view) the particles stop colliding. If I then press F11 again, it won’t collide anymore.

My problem though is that this is actually a random behavior, since sometimes they do collide in game and sometimes not. My example is just a deterministic way how to display this behavior always.

Is there any workaround or are we doing something wrong?

a lot!
Jan

Hi metamorphium,

I was unable to reproduce your issue. Could you narrow down a few things for me? Are you using two separate particle systems or one system with two emitters, I was a little confused by your wording. Also, how are you spawning the second effect, the assumed method is the use of the event generator inside the particle system (see screenshot).

112279-collision+event.jpg

Also, try to reproduce this in a blank project with only the assets needed and let me know how that goes.

,

Ed

Hi Ed,

thank you for taking time to look into my issue. Sadly it still doesn’t work. Here is my setting:

112303-p1.jpg

112304-p2.jpg

Please note, that it always works correctly in the editor, sometimes works in the game but always stops working when I press F11. Any idea what else should I check?

Alright, I’ve created a reproduction project using a default level, simple terrain and the particle system.

Steps to always reproduce faulty behavior:

  1. Download https://dl.dropboxusercontent.com/u/35645646/unreal/Test.zip
  2. Run the game in PIE - small window
  3. Press F11 to put it full screen
  4. Press F8 and move around a bit - particles stop colliding.

I also tried with 4.13.1, but the result is the same.

Hope this helps,
Jan