Buggy performance if "trailing" a moving object

I wrote up a simple app that uses the accelerometer to move a ball around the confines of the screen. It’s works great, but I noticed that if I want to leave the trail there behind the ball - accomplished by not calling background at the beginning of the main draw() method - then things will start to flicker on the screen during execution, and the reset button doesn’t seem to actually reset.

I noticed on the FAQ that background shoud be called in draw() all the time, is this the expected behavior if that’s not done? Any best practices / recommendations on drawing a trail in a different way?

For now you might want to try calling background() in the draw method once at the start to clear the framebuffer of whatever was drawn last run.

The flickering is a known issue and is due to the way the rendering works. We are looking into improving this in a future release.

If you look at the way the “Handling Touches” example does trails - it draws a transparent rectangle over the whole screen every frame. There is some flickering at the start but it will go away after several seconds.

In the “Handling Touches” example, those trails are exhibiting the same issue I was noticing in my code (if you move your finger to fast, it gets very flickery). However, I take it from Dylan’s reply that it’s going to be resolved in a later fix.

Thanks guys.

Jamatz - this seems to be an issue with the way iPad does its triple buffering. It will continue to happen on the handling touches example, however we are changing the default behaviour of new projects to clear the frame buffer before drawing.