We have a CoreGraphics implementation written on top of Cairo (Opal). This would make sense for implementing UIKit, since custom views in UIKit will all use CoreGraphics.
Cairo supports rendering to an OpenGL texture. Banlu did some work to render AppKit views to textures - this sort of thing would be a good base for the CoreAnimation stuff.
Sounds like something I *really* need to dig into.
> Targeting SDL and GL or SDL and Cairo might make things more universally portable.
>
> Any thoughts?
OpenGL doesn't make sense for 2D drawing - it lacks things like antialiased beziers, for example, which are the fundamental drawing primitive of all Cocoa stuff. This needs to be layered on at a higher level, which is what Cairo does.
SDL makes some sense. Gregory and I discussed this a while ago. It's on the list of 'things that would be good if someone had time to work on them'. I think Android has an SDL implementation, so if we could use SDL for events and window management, Cairo for drawing layers and OpenGL for compositing layers, then this would give us a back end that was fairly universally portable.
That sounds awesome.
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