Am 27.09.2009 um 08:50 schrieb Graham Cox:
I have used this approach to simulate an oscilloscope display and it works well in terms of realism, but performance can be an issue. You'll probably need to store at least 3 or 4 "previous" frames to get the effect you want - there's no really good way to do it in one pass and get realism.
One way to improve performance would be to use CALayers or CGLayers. Have a pool of five previous layers, and reuse the oldest of those for the new image. By using layers, you can let the graphics card do the merging of the six frames, and the expensive drawing only happens once. Play with the layer alpha to have them fade out.
Haven't tried this, but it's something I'd attempt if I was pressed for performance.
Cheers, -- Uli Kusterer "The Witnesses of TeachText are everywhere..." http://groups.yahoo.com/group/mac-gui-dev/ _______________________________________________ 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
