UIListLayout lags when scale is included in a child component

Bug Reports Engine Bugs
#1

This bug happens when you have a UIListLayout with Scale and negative offset as properties. This is especially messy because it breaks animations on UIListLayout.

It appears as if recalculation sometimes delays 1 frame.

Reproduction

Open up the place and resize it vertically.

UIListLayoutLag.rbxl (17.0 KB)

Gif:

ResizingBug

This happens in studio in the latest version. It also happens online (not confirmed recently). As far as I know, this bug has always existed.

Stats Windows 10, Studio 0.327.0.184115

Does not happen when tweening

So this doesn’t happen when you’re animating it with a tween. Updated repo that shows this isn’t the case

UIListLayoutLag.rbxl (17.9 KB)

Still happens when resizing studio.

Does happen on tweening if you listen to AbsoluteContentSize

So this actually does happen when tweening if you listen to AbsoluteContentSize changing and base resizing off of this.

UIListLayoutLag.rbxl (17.9 KB)

In this case

#2

I’ve added this to our backlog. It’ll be fixed by my upcoming changes to the GUI system. However, I would like to explicitly support this usecase of having an object in a list that soaks up the remaining space in a list layout.

3 Likes
#3

Upcoming changes to the GUI system? Care to elaborate? Is it just internal changes?

1 Like
#4

I am redoing the backend code responsible for sizing and positioning UI objects and fixing a lot of bugs in the process.

5 Likes