Cpu particle collision on mobile issue?

When play in editor or in mobile preview,everything works ok.But on actual devices such as iphone6 plus(es2) or android(atc),the collision does not work properly so that the eventgenerator and the eventreceivespawn does not work,in my case ,the ripple does not spawn when the rain hits the water plane(static):here are the screenshots of the issue:the first one is taken from PIE and the second one is taken from the iphone6 plus(ios9):

And here’s the particle collision module settings:

and the event generator settings:

59008-particle+eventgenerator.png

and the eventreceivespawn module settings:

59009-particle+eventreceivespawn.png

All my settings should be working but actually not…Why that happens on mobile?Thanks very much!

Hello his333555,

From your screenshots and your description you are attempting to create mesh distance particles inside of your mobile game.

I have researched this issue and found that this :

A little closer screenshot for clarification.

This is why whenever you package your project to your device that you cannot see the ripples. Mobile devices run on Open GLES2 and not Directx11. I am sorry but at this time this feature is not supported on mobile devices.

Thanks very much!But actually I’m using cpu particles not gpu particles so it should have worked on mobile.And strange thing is that if I create a clean project this issue doesn’t show…I really don’t know where I am missing…Thanks again!

I‘m not using GPU particle actually,so that’s not the distance field particle collision…

Hello his333555,

That is interesting. You said that you can open a clean project and it work as expected. I can try to test this on my end with a copy of your project.

You can send me a private message on the forums by going to the forums and going to the advance options. After that you can type in my name and send me a private link.

Hell his333555,

I haven’t heard from you yet. I was wondering if you were willing to send me a copy of your project to allow me to test it?

Thank you,

Thanks very much!But my project is so large and my network upload speed is too slow,I don’t think it can be uploaded successfully.Sorry for that…

Hey,

So I was able to throw together a project and tested it for iOS and Android. I have verified that the collision issue is only occurring on the iOS device. With or without the ‘drop detail’ box checked off, or the collision distance set at a high number, it did not matter on the iOS device, the particles simply fell through the ground. With that being said, I have submitted a report (UE-21422). Please check on this in a couple of weeks to see the progress.

Thank you for reporting this, have a great day! :slight_smile:

Hi,

Could you switch off “Drop Detail” option in ParticleCollision module? If this fixes issue then there must be wrong project settings related to Framerate.

  1. Open Project Settings → General settings and find Framerate category there.
  2. Make sure that “Min Desired Frame Rate” is set to a smaller number than 30.

When game framerate falls bellow “Min Desired Frame Rate” engine disables collision check for particles if they have “Drop Detail” option on. By default IOS projects has fixed 30 fps target. So you need to make sure that “Min Desired Frame Rate” is smaller than IOS target fps.

Thanks very much!That works!