Trail Behavior Changed?

I am not sure if this is the correct category but I could not think of where else to put this.

I went into a game that I have to test out some new features on when I noticed something strange:
There is a trail that I have that circles around a fixed point and changes in height. Previously, it would make one complete rotation before disappearing, but now it disappears only a quarter of the way through its revolution. I went into a game that I know did something similar with trails and found that they had the same issue. Did Roblox change the way that trail lifetime behaves?

This should go all the way around in a loop.
strange trail behavior


Could you add a picture or a GIF/Video so we could see this happening?

Sorry, forgot to do that, its added now.

It might be because it’s being drawn to a different song. The trails vertical movement also counts toward its length, so maybe a different song with higher peaks will use up that length a lot quicker.

Are you sure your graphic level is set to maximum? If that doesn’t fix the issue, maybe just attempt increasing the lifetime as you done before?

Its maximum is set to 0, so that is not the issue.

My graphics level is set at 10, I have just changed its revolution speed for now.

This new behavior seems to have been caused by a recent Roblox update and has affected my custom effects negatively.

Is this a bug that will be reverted, or should I start multiplying the lifetime of all my Trail objects by 4?


I’ve noticed this happening as well, it’s bad enough that I wish I had a before and after image.

Could we at least get confirmation on whether or not this new behaviour is intended?

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Yeah something has definitely changed. Here are some before and after shots of rain particles in my game.


These photos are from 4ish months ago and we can clearly see the raindrops and their stretched diamond shape.


Yes it is raining in this picture. The trails have shrunk sideways and longways and their shape has turned into a rectangle without me changing anything.


I’ve also noticed that the length varies in length depending on your FPS too.
The higher your FPS, the shorter the trail.

30 FPS

60 FPS

144 FPS

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Oh wow, I noticed that too but I didn’t make the connection that it was based on FPS. I thought that maybe my raindrop animation code was being slowed down by low FPS but that wouldn’t make any sense since it’s not tied to FPS.

@UltChowsk this thread should be moved to #platform-feedback:engine-bugs

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I have a suspicion that the unannounced trail behaviour change is because of a change in how trails are handled.
My trails look identical when I cap my FPS to 30 to as before the unannounced change around 2020-06-02T22:00:00Z.

So knowing that, I can only theorize that Trails were likely moved from being handled by LuaStep to RenderStepped, as LuaStep also works on 30 ticks.
Next to that, I also do not recall trail behaviour changing so drastically (or changing at all) when uncapping your FPS above 60.

Why do players on laggier hardware want longer trails?

Put your complaints here: