Re: Dirty rects getting merged together makes for inefficient drawing
Re: Dirty rects getting merged together makes for inefficient drawing
- Subject: Re: Dirty rects getting merged together makes for inefficient drawing
- From: Uli Kusterer <email@hidden>
- Date: Tue, 20 Oct 2009 12:54:54 +0200
On 19.10.2009, at 23:58, Ben Haller wrote:
On 19-Oct-09, at 5:27 PM, Dave Keck wrote:
Would NSView's -getRectsBeingDrawn:count: help?
Well, I'm already using it in my own code where appropriate. (Or
actually I'm using -needsToDrawRect:). But the problem is that a
whole bunch of NSTableView cells are getting drawn that never got
invalidated.
That's like saying: "I'm using the setter, why would I need to use
the getter?"
The dirtyRect parameter passed to drawRect: is the union of all
redraw rectangles. So, it's the smallest rect that encloses all the
dirty rects. drawRect: does not get called for each redraw rect. If
you want the individual sub-rects, use getRectsBeingDrawn:count: and
loop over all those rects and draw the individual parts.
Cheers,
-- Uli Kusterer
"The witnesses of TeachText are everywhere..."
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden