On 08/06/2012, at 12:30 PM, gweston wrote: > On Jun 07, 2012, at 10:22 PM, Graham Cox <graham....@bigpond.com> wrote: > >> >> On 07/06/2012, at 9:23 PM, Gregory Weston wrote: >> >> > Does anyone know of existing code or a trivial technique to get a CGPath >> > or NSBezierPath that describes the shape of the desktop? I'll write and >> > share it if it's not out there, but I'd rather not reinvent any wheels. My >> > interests are: >> > >> > 1. It should be the actual perimeter of the desktop, not just the bounding >> > box. >> > 2. It should be a single polygon, rather than a collection of rectangles. >> > 3. It should behave properly in the presence of mirrored displays. >> >> >> Just iterate over the list of NSScreens and append each screen rect to a >> bezier path. > > First thing I tried. It fails requirement #2.
OK, so you'll need to get smart, and determine where the edges connect. With a few simple rectangles, calculating this union is a very easy problem, unlike, say, the general case of a union of arbitrary vector paths. But that can be solved, so this case is a very degenerate subset of that problem, since you know there is no overlap, nor any gaps. I don't believe there is a built-in solution for union (or other set ops) on bezier paths, much as I'd love there to be, and have had in as a bug report for a requested feature since about 2004. The old MacOS could do this with regions (though that was a bitmap operation, so definitely simpler), but OS X has never had a public API, even though one must exist internally to calculate clipping paths and so on. --Graham _______________________________________________ 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
