Quartz (Macintosh): Meaning (information, definition, explanation, facts)

Quartz is the graphics layer that sits on top of the Darwin core of Mac OS X, sometimes also referred to as CoreGraphics. Quartz directly supports Aqua by displaying two-dimensional graphics to create the user interface, including on-the-fly rendering and anti-aliasing with sub-pixel precision.

Quartz supersedes Quickdraw which was used in earlier versions of the Mac OS, known as "Classic".

Quartz is based on version 1.4 of the Adobe Portable Document Format (PDF — a universal file format that preserves all of the fonts, formatting, colors and graphics of any source document, regardless of the platform used to create it.)

It is descended from NeXT's Display PostScript.

Quartz differs from QuickDraw in a number of key areas. QuickDraw is inherently based on raster graphics, where the fundamental graphical entity is the pixel. Everything is defined in terms of pixels laid out on a 2-dimensional integer grid. Quartz instead takes a more mathematical approach, where the coordinate space is an abstract concept defined by real values in 2 dimensions. Points in this space can be connected to form paths, such as straight lines, bezier curves, and so on. To create actual graphics on the display, the paths are rasterised as needed to generate the pixels at the display device's resolution. This permits the same graphics commands to yield the same output on any device using the best resolution available. As in PostScript, paths can be "stroked" to give outlines, lines and so forth, and closed paths can be filled to create solid shapes. Text is generated simply by paths formed into the shapes of the text glyphs.

Quartz Extreme

Starting with Mac OS X 10.2, Quartz was extended by Quartz Extreme, which leverages OpenGL in order to render screen displays faster by presenting them as textures within a 3D OpenGL context. This permits faster compositing of screen images using 3D hardware acceleration.

To use Quartz Extreme, the Macintosh must have an AGP video card installed with a minimum of 16 MB of VRAM.