Rain effect in PopcornFX

Hey there,

I’m currently making a rain effect on a windshield in popcornFX, I want to keep on working on it but i don’t know how to go further.
Another problem I’ve got is that I cant get a animated collision mesh to work. I have a collision mesh but it’s static at this moment in time.

Link to gif effect

Can anyone give any pointers / feedback, this would be much appreciated!

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Hello !

With which engine are you working with?
You can also join the popcornfx channel on the discord !


Sorry that I haven’t gotten back to you.
I can’t disclose the engine because I’m under NDA.

I’ll join the discord to further up my FX.

Thanks for your awnser!

First of all, I propose not to use collision mesh, but some procedure to define where windshield wiper is. (You will save a lot of performance with that). Just make some attribute for effect, that defines wiper angle, size, etc.

Then you will be able to control with the same attributes geometry in engine and data in effect. Also with attributes like wiper length, etc. you will be able to make customization of effect for different car models.

Then you can kill (or, what I prefer, change LifeRatio to point, where particle starts changing transparency to 0.0, but only if it’s fast enough) raindrop particles based on theirs position if it intersects with wiper. Also as you have actual wiper position, angle and size, then you will be able to spawn some particles to imitate water accumulation, on the side of wiper movement direction.

Also good to have some ribbons on back side to imitate thin layer of water that dries out.

That’s just my 5 cents. Good luck with the effect.

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Hello guys,
I have a new iteration on the effect. I’ve kind of used the logic of Dmytro. I’ve looked at the effects that you could install with popcorn and then I saw my solution.

I’ve used the animation mesh to still be a base for my collision detection but then spawned particles on it and with the use of those particles combined with spatial layers i had my collision detection.

Now i’m wondering how I would do the cohesion of the water / rain. I’ve looked at metaballs but I’ve heard that this is not possible within the PK shader.

If anyone has a clue on how to achieve this please let me know or if you have further improvements.

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Hey, in case you will need the script solution, there are some thoughts:

You can download sample effect trough:
GDrive Link to PKFX file


Other solutions are always welcome, thanks !