Nick, I'm using [NSView setNeedsDisplayInRect: r] and [NSView drawRect: r], so I'm not explicitly flushing and that's not goofing things up. Beam-sync is related to flushing, I think. I don't know how to turn it on or off programmatically and it does not appear in QuartzDebug -- I think it was removed in Snow Leopard or the newest XCode. It might be renamed to AutoFlush drawing.
However, I've found that I was not using the right CG function: I was using CGContextDrawTiledImage() and should have been using CGContextDrawImage(). In my early testing I came to the mis-conclusion that CGContextDrawTiledImage() was faster. It is actually about twice as slow. I was jumping between machines and not being methodical about my testing. I've redone speed tests and now if I don't stretch the window, the screen update is fine on my new iMac. If I do stretch to full screen, CGContextDrawImage() takes about 80 ms and CGContextDrawTiledImage() takes about 140ms. Then I turned on QuartzGL (which I had never heard of until your email, thanks) with HIWindowSetBackingLocation(windowRef, kHIWindowBackingLocationVideoMemory). Now, CGContextDrawImage() takes 4ms or less to update the entire screen. This is beautiful. I still need to test on my Tiger, PPC mac. I'm thinking screen updates with Quartz will be a problem there, but I don't know yet. I might have to use a separate executable with QuickDraw. I use copybits in my own dirty rectangle handling in Carbon code. [NSView drawRect: r] seems to coalesce all the dirty rectangles into one big rectangle that also contains a lot of area that is not dirty. My old code has smaller, non-overlapping dirty rectangles updated with copybits which should be more efficient. Conclusion: * Quartz is actually sufficiently speedy to update the screen, at least on a new mac. * QuartzGL is great, esp when stretching the image. * Not sure about Tiger (no QuartzGL) or older machines yet. Might need to stay with QuickDraw/copybits. Thanks for your help. I would have wasted a lot of time with CoreAnimation, which I don't need for this project. Joel On Feb 23, 2010, at 5:50 PM, Nick Zitzmann wrote: > > On Feb 23, 2010, at 4:35 PM, Joel May wrote: > >> Thanks for the info about drawing in a different thread. I won't waste my >> time and sanity. I guess I need to figure out how to speed up the drawing >> instead and keep it in the main thread. > > How often does your app flush its changes? If it's more than 30 f/s, then > you're wasting redraws, and either need to disable beam sync, or cut back on > the animation. You can use Quartz Debug to find out, and control the beam > sync feature. > > Did you also try QuartzGL? It didn't work correctly in Tiger, and it's off by > default in Leopard & Snow Leopard, but it ought to work on most Macs. Again, > you can experiment with this using Quartz Debug. > > Nick Zitzmann > <http://www.chronosnet.com/> > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) 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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
