flickering of scrollbar and player controller in El Capitan

[Martin Koob]

I have a LiveCode application that uses a few player objects, some controlled by their own controller and one controlled by a Livecode Scrollbar. I was testing it on El Capitan and noticed that as a movie plays or the thumb on a scrollbar is advanced by script the background of the player controller or scrollbar flickers between black and white. Another thing I noticed is that when the mouse is over buttons with a black background the background changes to white then back to black. I have not noticed this before on previous OS's I am using LC 6.7.3. Has anyone seen this or has reported this as a bug?

Martin

[Martin Koob]

I posted bug reports and have uploaded videos demonstrating the issue.

http://quality.livecode.com/show_bug.cgi?id=16834

http://quality.livecode.com/show_bug.cgi?id=16836

One other bit of info. This is on a iMac 27" 5K retina. Could that be causing issues with redrawing the controller or scrollbar?

Martin

[Martin Koob]

The bug has been confirmed. It is an issue with Mac OS X 10.11 'El Capitan' pushing changes to the screen more frequently than LiveCode wants.

While resolving this bug is being worked on do people have any ideas of how to mitigate this? Would locking or not locking the screen have an effect on this?

Martin

[okk]

Hi Martin,
this flicker indeed looks horrible. I noticed a similar flicker in some teststacks during videoplayback - not in the controller but in the videos themselves - (MacbookPro / MacOS 10.10.5 / LC 7.1 / 8 DP14) , but more rarely, perhaps every 25 frames or so.

As a workaround a movie controller that is basically a simple line might be worth trying. A bit like the YouTube controller... I once used it for a video installation, so I wanted a very minimalistic progressbar; I am sure this could be modified into a fully functional movie controller. The player was stretched over the whole stack, the script was located in the player object itself.

Code: Select all

on updateprogress 
  global stackwidth -- contains the width of the stack
  put the duration of me into movielength
   put the currenttime of me into movieprogress
   set the points of graphic "movieprogress" of card "player" to 0, the bottom of me+1, (round(movieprogress/movielength*stackwidth)),  the bottom of me+1
   if movielength > (movieprogress +5) then
      send updateprogress to me in 20 milliseconds
   else
     -- stop player etc.
   end if
end updateprogress 

Best
Oliver