I’m posting this in hopes there’s an obvious fix. My efforts so far to get a minimal reproducible example have been unsuccessful, though we can reproduce the error in its original context. We’re on Ubuntu 16.04 on a Dell Laptop using onboard Intel graphics.
My lab is running an experiment in which we draw a “ball” (red circle) onscreen that’s controlled by joystick. We also have a function that marks events for a photodiode by drawing a white circle in a corner of the screen to “spell out” a bit pattern.
Here’s the issue: I found that we were having flickering problems with the other onscreen stimuli while calling our function to mark events. Normally, this would be because we were flipping the screen without having a copy of the stimuli on both buffers (front and back), but we were also having to call
flip one more time than necessary to clear buffers at the end of all this.
So I ended up simply running the following code at the same point in my script where the flicker problems arose:
for i in range(10): win.flip(clearBuffer=False) core.wait(1)
What I expected was that the screen would then toggle between the contents of the two buffers, exchanging front and back. Instead, I got a cycle through the last four positions of the red circle.
I realize this is short on lots of details, my confusion arises from the fact that simply flipping the screen seems to get me four distinct sets of visual information.
Is there something simple we’re missing?