Shapes sometimes disappear when animated

[DaanLubbers]

Hey everyone,

I am animating (resizing + moving) some rectangles and primitive_text objects to visualize some data in a stacking bar graph. It works properly, but I am facing a peculiar issue which I believe could be a bug. Sometimes some of the animated shapes disappear. They will sometimes reappear on a subsequent animation call, but they always reappear if the screen is forced to redraw (by resizing the window for example). Given consistent input it seems that the same objects disappear and reappear at the same time every time.

I have attached a minimal example panel and gif which illustrate the issue. When I press the button for the 5th time the issue happens and the rectangle disappears until the panel redraws.

I also found an older thread which apparently describes the same problem which was supposedly fixed before here: viewtopic.php?f=15&t=8492&p=963608&hilit=redraw#p963608

I am running version 3.16P015 64 bit.
I also verified it on another machine running version 3.16P014 64 bit.

Can anyone confirm this behaviour and/or whether this is indeed a bug or not? Any workaround suggestions are also appreciated.

[leoknipp]

I have tested and I could reproduce the problem.
I did not find a work around for it, e.g. it tried to set the rectangle invisible and visible.
The problem was reported to our development department.

Best Regards
Leopold Knipp
Senior Support Specialist