Decal Lifetime Opacity not working?

Development Rendering
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So, I am trying to fade decals out after a short dealy (this feels like it should be extremely simple to do). So at first I tried the “set fade out” node which didn’t work. After some googling and reading the documentation I found out that I had to add a “decal lifetime opacity” node to my decal material". So I did, but still no fade, they all just disappear instantly after the delay. I know I could just do a dynamic material, but that feels stupid when there is a built in function for it. Also i am trying to apply the effect to around 20 decals at the same time. I also found this twitter post https://twitter.com/highlys.../status/1265096709622775809… that also mentions the lifetime opacity. Am i plugging it in the wrong way in the material editor? Anybody know what i am missing here? feels stupid on getting stuck on something that should be so simple to do. Appreciate any help

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Hi, posting this answer here since I found this while looking for an answer, you simply have to call SetFadeOut on your decal component

Blueprint Doc link : Set Fade Out | Unreal Engine Documentation

C++ Doc link : UDecalComponent::SetFadeOut | Unreal Engine Documentation

Only after setting the Fade Out will the Decal Lifetime Opacity work properly, you can also use SetFadeIn to have a fade in effect

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I’m at UE5.6
My decal can’t fade out even if I call SetFadeOut() on my decal component and plug in the DecalLifeTimeOpacity node in my decal material.

Any ideas?

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Hi! Have you found a solution to this problem?

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I was able to solve this problem in my project in UE 5.6!

  1. Make sure that in the decal material the “Decal Lifetime Opacity” is connected to the “Opacity” input.

  2. If you spawn a ready-made BP Actor, then add it to the Event Graph: EventBeginPlay → CreateDynamicMaterialInstance → Delay → Set Fade Out.
    Don’t forget to connect your Decal to the “Target” input.

  3. Change the “Duration” values in “Delay” (its lifetime decal).

  4. Change the “Duration” values in “Set Fade Out” at your discretion (its Fading time). Inportant! The “Start Delay” must be zero!

For Example:

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