Any ideas on how to make a laser beam that lags behind?

Hi all!
I’m trying to create a laser sight that ‘lags’ behind, fanning out as the player rotates, kind of like this:

I currently have a beam particle emitter where a blueprint sets the source and target every frame and it works great, but I can’t figure out how to make it drag behind if it moves too fast.

I tried enabling motion blur but as expected that blurs the whole screen, I’d like this to be an effect only applied to the particle. I also looked into the smear material effect but it didn’t do the trick for me, possibly that only works on meshes/mesh particles.

Thanks everyone! :slight_smile:

Just wanted to add since posting this I tried faking it by manually scaling the beam particle as the player rotates - which is sorta working, but I’d love a more “correct” solution. :crossed_fingers:

Hello Blondielass,

There is a ‘SpringArm Component’ that has some tweakable lag variables. (It’s called camera lag, but should work with any actor attached to it.)

If you try this - Let us know how it goes!

I forget the proper term, but he’s referring to the bit of smear at the end of the beam.

Below is my suggestion for adding smear, but what they're doing is exactly what you're doing. They're just scaling up based on rotation speed and distance from the player. It looks good thanks to the noise in the brightness, but it's fundamentally similar.

Spawn more particles on update rather than spawning one beam at the start- the ribbon will take care of the rest.
Though not directly an answer, this video has some useful info:

Thanks rokenrock :+1: I’ll give that video a watch - sounds like I’m maybe on the right track just need to improve it a bit.

I love that guy’s videos too, totally missed this one!

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