Re: [Matplotlib-users] Animation Broken WXAgg OS X

[Ken M. <mc...@ii...>]

On Mar 10, 2006, at 2:56 PM, Christopher Barker wrote:
> This might have something to do with the fact that OS-X double  
> buffers it's windows, so you need to force and update event  
> somehow. A call to wx.Window.Refresh() and/or wx.Window.Update()  
> might do it.

For `examples/anim.py', calling line.axes.figure.canvas.Update()  
after each call to pylab.draw() appears to do the trick.

> Maybe OS-X waits for a Idle event to update the screen.

The wxWidgets documentation for wxWindow::Refresh() and  
wxWindow::Update() indicates that the event loop is the default  
method for driving screen repaints.

> What kind of app would you have running without an event loop anyway?

Apparently, pylab scripts that try to animate plots by redrawing them  
run without an event loop.  I could be mistaken, but I don't think  
the loop is started until you call pylab.show().  See `examples/ 
anim.py' for an example of what I'm talking about.

> Id didn't think you could do much at all without one in wx.

I didn't think so either but I hadn't considered pylab.  Since a  
matplotlib example was the initial source of the problem, I think we  
should probably change things so that Update() gets called when  
necessary.  My proposal is to tack the following (untested) lines to  
the end of backend_wx.FigureCanvasWx.gui_repaint():

	# force a repaint if we think we're a pylab figure
	if isinstance(self.GetParent(), FigureFrameWx):
		self.Update()

Ken