> On Jun 9, 2016, at 4:20 AM, Graham Cox <graham....@bigpond.com > <mailto:graham....@bigpond.com>> wrote: > > Why do you draw into a CGLayer rather than a CGImage? For a couple reasons: • Because I draw my shapes into a CGLayer with Quartz2D. I’m not working with images on disk or from streams. • As recommends in the Quartz2D docs, use GCLayers for repeated drawing of the same image. • CGLayers seems far simpler to work with than bitmaps.
I could use CIImage if I could use the CGContextPaths as inputs to the CIImage directly, but I can’t see how to do that. And CIContexts seem to be orthogonal to CGContexts. In my scenario, I have 4 layers that have a non-trivial shape drawn into them. The drawing for them is only done once, ever. Then they are drawn into a 5th layer with some offset depending upon the desired angle of the final image. This drawing is done each time the angle for the shape changes (like a clock hand). I rely on the “painters model” of overlaying the layers to get the effect I want. I couldn’t figure out any other way to do it. Here it is (reduced) — highlights/shadows with no color. Actual size is 512x512. Full-size image is here <http://www.quartertiltwo.com/image/IndentEffect_noColor.png>. Full-size image with color is here: <http://www.quartertiltwo.com/image/IndentEffect_blue.png>. _______________________________________________ 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
