[wxPython-users] Not quite understanding buffered DCs

[Christopher Barker]

Robin Dunn wrote:
> It is all for convenience.  That one line in the example replaces about 
> 4 lines it would take to do it without a wx.BufferedPaintDC.  In fact, 
> all of the buffered dc classes are entirely for convenience.  You can do 
> everything they do yourself with just a bitmap, a MemoryDC and a 
> ClientDC or PaintDC.

see:
http://wiki.wxpython.org/index.cgi/DoubleBufferedDrawing

for more detail

> [1] Although it is becoming a better practice to avoid using wx.ClientDC 
> and just call Refresh instead, and do all your painting from the 
> EVT_PAINT handler.  This is because with the newer CoreGraphics API on 
> OS X "out of order repaints" is much more expensive of an operation. 
> It's possible that other platforms may move in this direction as well.

I had a pretty good discussion with Stephan about this a while back, and 
  at the time, I think you pretty much needed to call Update() after the 
Refresh(), to make sure it got to the screen sooner than later. In this 
case, doesn't it do "out of order repaints" anyway?

-Chris


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