Getting a Beam Particle to Follow a Spline

I’d like to mirror a thread I have going on at the forums, as I think I’ve done everything correctly.

I’m trying to get a Beam particle to emulate a spline (I want the spline to update it’s positions in realtime, and there are a total of 16 splines each with 64 points in our game, so spline meshes are too performance intensive). I think I’ve set everything up correctly, but for some reason my beam is taking the longest possible route to the spline. Inverting the Tangent Vectors doesn’t give me the correct result either.

Is this a bug or an error on my part? Images in the thread!

Hi TheJamsh -

I think you were there, I have a tendency however to use the Particle Vector Parameters in my setup.

Here is the Cascade:

Here is the BP:

Here is the Results:

Thank You

Eric Ketchum

Hi Eric,

Thanks for taking a look. I still can’t get the results you have above, my splines just seem to fire off in a random direction even with the same set-up as yours.

I don’t suppose you’d be able to upload the files you used to create the spline above would you?

(I’m in 4.5.1 btw).

Hi -

Sorry one of the important things and I forgot to mention it, try this first, change the Source Strength and Target Strength both to 1. I’ve also attached the zip of the project for you to dig through.link text

Eric Ketchum

Awesome thanks Eric, I got it working, using a combination of my method and yours I can get a single emitter with beams to follow any length of spline, very happy!

I still can’t quite work out why you subtract 2 from the initial count, I think that’s where I was going wrong before.

Hey Eric , I too needed something just like this. I had one problem if you could help me out here.
I want the beam to be in XY plane but when I draw the spline dynamically the beam changes its plane and it looks really weird.
Thanks a lot…

Thanks for the screenshots! Finally get it working.

BTW, for whoever still figuring out, remember to set the Param Mode “DPM Direct”. This is important to make it work for blueprint editable particle system parameters. :slight_smile: