Particle Collision wont work in game

Hi there

As the title of this question says, Particle Collision wont work in game, and only when i drag and drop the particle effect on the map. Its basically a bullet hit with sparks that i want to collide against surfaces.

My particle coding seems to work fine, yet i dont understand why it wont work when i press play in my map and then i start shooting against surfaces. the sparks just go through objects and surfaces.

I really want particle collision in my game.

Any idea why is this not working in game?

Thanks!

Hey Bruno_G -

Are you setting up the particle with a collision module in Cascade, and what is the min and Max number of collisions set to as well?

Yes Cascade of course,

And yes i do have a high number in number of collisions, yet how come it works by drag dropping the particle template on the map and not in game when i shoot at surface?

Thanks for the reply.

Hope we could find a solution

Hey Bruno_G -

If you are using the P_Sparks which is a GPU Particle system, the Scene Depth Collision will not work with a depth reading of anything besides height, in other words, they will collide with floor but not with a wall.

Try using a CPU,. “Default” particle systems and see if that collision modular offers you the functionality you are looking for. If you already are using a CPU system, please let me know and I will continue my investigation.

Thank You -

Eric Ketchum

Yeah i’m using CPU emitters.

A good example of what i need to achieve would be for example, a bullet hit effect. Picture like a big calibre like a 50 cal. gun.

I need:

1- to churn out little particles with collision to simulate debris flying around realistically. Yet this need to be in game also, not just while drag dropping the effect template on the map. At the moment when I go in game, the effect is assigned to my gun projectile against physical materials, it plays the effect when i shoot at surfaces yet collision wont work for some reason. Its a CPU effect in general, not messing with GPU just yet.

2- I need the dust it will produce (which will be another emitter) to have volumetric normal lighting as in illuminated by the sun light and colour of the map, like in this example:

I suppose this is within the normals of the material of my sprite, is there any good tutorial on this? really new into materials and blueprints.

3 - to be able to, have the dust receive lighting information from the environment. I don’t know if this is gonna be too expensive for performance but I would like to see the dust from the bullet hit become blueish if I shot next to a blue light. Am I making sense? Would this be possible?

Thank you for your responses. I just wanna make sure particle collision and lighting (producing or receiving) works in game to within effects that are once of like explosions and bullet hits.

There is a bug with CPU particle collisions we are currently looking into. Please stay tuned for an update. Sorry for the issue, I am seeing the same thing here.

any eta of when this might be fixed? i’m having the same problem - cpu particles work in game fine but not when the emitter is spawned from within a blueprint…

more than six months later and with 4.8.3 this issue is still not fixed.

Hello -

Particle Collision is working as intended now. If you are still seeing issues with you Particle Collision then chances are you need to adjust the Max Collision Distance in the Performance Subsection of the Collision Module.

This setting is in the Collision Module for Mesh and Sprite type emitters and its default value is only 1000 units for performance reasons as collision is quite expensive for particles. You can adjust that value upwards as is necessary for your project and particle system.

To clear up any confusion about this I setup an example project for everyone to have a look. It is a 4.8.3 project.

Thank You

Eric Ketchum

[Test_Project 4.8.3][2]

For me, the answer was unchecking “Drop Detail” under Performance under Collision Module