[Matplotlib-users] moving line

[Michael M. <mic...@gm...>]

I'm creating a simple little sound file editor, which includes the ability
to play a sound file as a vertical line (a "cursor") moves across the plot
of the waveform in sync with the sound. So the trick is, how to create this
moving line. First I tried FuncAnimation, but I had problems with the
synchronization with the sound. I'm guessing that the animation
capabilities of matplotlib weren't really designed to be synchronized with
outside activities. So then I tried using QTimer's and modifying the Line2D
instance that is the vertical bar. This didn't work unless I called draw()
on the figure canvas every time I modified the Line2D, which caused
slowdown (probably because my audio data consists of 1000's of points).

So is there a way to animate a vertical line moving across the plot with
good control over exact timing, in the presence of other plots with
thousands of points?

Mike