[plt-scheme] scrolling and painting

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Tue Sep 6 10:48:12 EDT 2005

At Mon, 5 Sep 2005 12:19:04 -0400, pedro pinto wrote:
>  I have a large image which I want to show in a canvas. I have used double 
> buffering, i.e. I draw the entire thing onto a bitmap and copy the bitmap to 
> screen on the paint callback. Unfortunately I still some flickering when I 
> scroll the canvas. 

Create the canvas with the 'no-autoclear style.

>  Additionally, when using init-auto-scrollbars how can I tell what the 
> scroll position is?

The `get-view-start' method reports the offset in drawing coordinates.


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