What's the difference between Quartz Core, Core Graphics and Quartz 2D?
Quartz frameworks and their APIs
CoreGraphics.framework
- Quartz 2D API manages the graphic context and implements drawing.
- Quartz Services API provides low level access to the window server. This includes display hardware, resolution, refresh rate, and others.
QuartzCore.framework
- Core Animation: Objective-C API to do 2D animation.
- Core Image: image and video processing (filters, warp, transitions).iOS 5
Quartz.frameworkOS X only
- Image Kit: display and edit images.
- PDF Kit: display and edit PDFs.
- Quartz Composer: display Quartz Composer compositions.
- QuickLookUI: preview media elements.
All three frameworks use OpenGL underneath because all drawing in iOS or OS X goes through OpenGL at some point. See the section Media Layer Frameworks of the Mac OS X Technology Overview for details.
Other "Quartz" technologies you may have heard of:
- Quartz Extreme: GPU acceleration for Quartz Composer.
- QuartzGL (aka "Quartz 2D Extreme"): GPU acceleration for Quartz 2D.
These are internal implementations of GPU rendering, not APIs. They decide whether to create the window buffer in the CPU and only use OpenGL to upload as a texture (the default) or to do the whole rendering using OpenGL, which not always improves performance. You can alternate between the two using the QuartzGLEnable Info.plist setting. For an explanation see John Siracusa review of Mac OS X 10.4 Tiger, pages 13 and 14.
“Quartz” and “Core” are marketing names sprinkled over frameworks and APIs in a random manner. If they wanted to create a confusing naming mess, they succeeded.