On May 5, 2012, at 4:46 PM, Jens Alfke <j...@mooseyard.com> wrote: > > It does that, but the results may not always be exactly what you want. :) The > default behavior is to antialias, so if you stroke a one-point-wide black > rectangle on integer point boundaries (assuming the usual 1pt==1px scaling) > you will in fact get a two-pixel wide gray rectangle. Which is probably not > what you wanted. This is because the edges are on pixel boundaries so the > strokes are going halfway through the pixels on either side. The solution as > I said is to add 0.5 to the coordinates so that the stroke edges fall on > pixel boundaries. > > (IIRC there are some AppKit geometry utility functions that will adjust > coordinate values to fit pixel boundaries in a resolution-independent way. I > don’t remember their names offhand.)
-centerScanRect:, -convertRectToBacking: and friends. Which if I understand correctly you should now *always* use instead of adding half pixels because of HiDPI. > > Someday every device will have retina-quality graphics and these details > won’t matter It still matters because coordinates in Quartz always refer to the infinitely thin space between device pixels. --Kyle Sluder _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
