Quartz (graphics Layer) - Quartz 2D & Quartz Compositor

Quartz 2D & Quartz Compositor

Quartz 2D is the primary two-dimensional (2D) text and graphics rendering library: It directly supports Aqua by displaying two-dimensional graphics to create the user interface, including on-the-fly rendering and anti-aliasing. Quartz can render text with sub-pixel precision; graphics are limited to more traditional anti-aliasing, which is the default mode of operation but can be turned off. In Mac OS X v10.4, Apple introduced Quartz 2D Extreme, which allows Quartz 2D to use supported GPUs for rendering. In Mac OS X 10.4, Quartz 2D Extreme is not enabled by default, because it may lead to video redraw issues or kernel panics. As of Mac OS X v10.5 Quartz 2D Extreme has been renamed to QuartzGL. However, it still remains disabled by default, as there are some situations where it can degrade performance, or experience visual glitches; it is a per-application setting which can be turned on if the developer wishes.

Quartz Compositor is the compositing engine used by Quartz 2D and other renderers, such as OpenGL, Core Image, and QuickTime. In Mac OS X 10.2 and later, Quartz Compositor uses the processors (GPUs) on supported graphics cards to vastly improve composition performance. This technology is known as Quartz Extreme, and is enabled automatically on systems with supported graphics cards.