Controlling a scrolling texture's U value within a blueprint function without timeline

[Soaron]

I’ve created a Material Parameter Collection with a Scalar Parameter that controls the U scroll speed of my material - When I Set the Scalar Parameter within my blueprint’s function, the set value works perfectly well except for the fact that I can’t control when the scrolling starts.

So every time I spawn the object that uses the scrolling material, it appears scrolling at a different point. I want the scrolling happen 0 to 1 every time.

I’ve seen people solve this issue using a Timeline, but apparently Unreal does not support adding Timelines within Functions? There even seems to be a plugin for this:

https://www.unrealengine.com/marketplace/en-US/product/component-timeline/reviews?sessionInvalidated=true

Is this really the only solution here? Is there no other way except for a timeline to control the precise point of a scrolling texture’s starting point?

Thank you!

[Arodi007 (Pixiebell Games 💼)]

Am not sure if i understand correctly, you are using panner or function timer to move material up down ?

Blueprint function doesnt allow latent node(any node with the clock icon) inside, which mean there no waiting in a function. (that is no async node like save async)

Any waiting function should be done in the event graph.

[Soaron]

Yes, it’s using a panner
Here’s the section in the function that sets the scalar value

Before that you can see I’m spawning the projectile, which uses the scrolling texture

This is how it’s set up in the material

[Soaron]

In case anyone bumps into the same thing, this other forum post had the anser:

Timeline in a function?

Functions can only contain calls that finish instantly, and things like timelines and delays do not. If you need a function to execute a timeline, you can for example place a custom event (that triggers a timeline) in the main event graph, and then have your function raise such an event to start the timeline.

Confirmed it works!