Quartz Compositor
Encyclopedia
Quartz Compositor is the windowing system
in Mac OS X. It is responsible for presenting and maintaining rasterized, rendered graphics from the rest of the Core Graphics framework and other renderers in the Quartz technologies
family. Internally, it is also known as WindowServer.
, OpenGL
, Core Image
, QuickTime
, or other process is written to a specific memory location, or backing store. The Compositor then reads the data from the backing stores and assembles each into one image for the display, writing that image to the frame buffer memory of the graphics card. Quartz Compositor only accepts raster data, and is the only process that can directly access the graphics frame buffer.
In managing individual windows, Quartz Compositor accepts a bitmap
image of the window's contents from its renderer, along with its position. The choice of the renderer is up to the individual application, although most use Quartz 2D. Quartz Compositor then acts as a "visual mixing board," by adding the given window to the whole scene for the display.
In its role as window manager, Quartz Compositor also has an event queue which receives events, such as key strokes and mouse clicks. The Quartz Compositor takes the events from the queue, determines which process owns the window where the event occurred, and passes the event on to the process.
introduced Quartz Extreme: graphics processor (GPU) acceleration for the Quartz Compositor. With Quartz Extreme, no central processor (CPU) cycles are utilized for scene composition. Quartz Compositor runs using the graphics processor (GPU) by encapsulating each rendered backing store in an OpenGL texture map or surface. The GPU then composes the surfaces and maps to provide the final image, which is delivered to its frame buffer.
Quartz Extreme only uses OpenGL commands, and requires a graphics card connected to an AGP
2X or faster bus (including AGP 4X, 8X, and PCI Express
), supporting textures and maps of arbitrary size, since many of the renderers have no size limitation (Quartz 2D for example). It is automatically enabled on Mac systems with one of the following types of graphics cards:
. QuartzGL will be disabled once again upon quitting the Quartz Debug utility. A workaround is to force quit the Quartz Debug application, which will leave QuartzGL enabled system-wide.
All graphics cards capable of supporting Core Image
also support QuartzGL.
As of August 2011, no non Apple web browser fully support GPU hardware acceleration based QuartzGL for rendering contents. Mac OS X 10.7, however, includes an edition of the Safari browser with full hardware acceleration support.
Windowing system
A windowing system is a component of a graphical user interface , and more specifically of a desktop environment, which supports the implementation of window managers, and provides basic support for graphics hardware, pointing devices such as mice, and keyboards...
in Mac OS X. It is responsible for presenting and maintaining rasterized, rendered graphics from the rest of the Core Graphics framework and other renderers in the Quartz technologies
Quartz (graphics layer)
Quartz specifically refers to a pair of Mac OS X technologies, each part of the Core Graphics framework: Quartz 2D and Quartz Compositor. It includes both a 2D renderer in Core Graphics and the composition engine that sends instructions to the graphics card...
family. Internally, it is also known as WindowServer.
Overview
Quartz Compositor is the sole facilitator for the placement of rendered bitmaps into the memory of the graphics card. The bitmap output from Quartz 2DQuartz 2D
Quartz 2D is the primary two-dimensional graphics rendering API for Mac OS X, part of the Core Graphics framework.-Overview:Quartz 2D is available to all Mac OS X application environments, and provides resolution-independent and device-independent rendering of bitmap graphics, text, and vectors...
, OpenGL
OpenGL
OpenGL is a standard specification defining a cross-language, cross-platform API for writing applications that produce 2D and 3D computer graphics. The interface consists of over 250 different function calls which can be used to draw complex three-dimensional scenes from simple primitives. OpenGL...
, Core Image
Core Image
Core Image is a pixel-accurate, near-realtime, non-destructive image processing technology in Mac OS X. Implemented as part of the QuartzCore framework of Mac OS X 10.4 and later, Core Image provides a plugin-based architecture for applying filters and effects within the Quartz graphics rendering...
, QuickTime
QuickTime
QuickTime is an extensible proprietary multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. The classic version of QuickTime is available for Windows XP and later, as well as Mac OS X Leopard and...
, or other process is written to a specific memory location, or backing store. The Compositor then reads the data from the backing stores and assembles each into one image for the display, writing that image to the frame buffer memory of the graphics card. Quartz Compositor only accepts raster data, and is the only process that can directly access the graphics frame buffer.
In managing individual windows, Quartz Compositor accepts a bitmap
Raster graphics
In computer graphics, a raster graphics image, or bitmap, is a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium...
image of the window's contents from its renderer, along with its position. The choice of the renderer is up to the individual application, although most use Quartz 2D. Quartz Compositor then acts as a "visual mixing board," by adding the given window to the whole scene for the display.
In its role as window manager, Quartz Compositor also has an event queue which receives events, such as key strokes and mouse clicks. The Quartz Compositor takes the events from the queue, determines which process owns the window where the event occurred, and passes the event on to the process.
Quartz Extreme
Mac OS X v10.2Mac OS X v10.2
Mac OS X version 10.2 "Jaguar" is the third major release of Mac OS X, Apple's desktop and server operating system. It superseded Mac OS X v10.1 code name Puma and preceded Mac OS X Panther...
introduced Quartz Extreme: graphics processor (GPU) acceleration for the Quartz Compositor. With Quartz Extreme, no central processor (CPU) cycles are utilized for scene composition. Quartz Compositor runs using the graphics processor (GPU) by encapsulating each rendered backing store in an OpenGL texture map or surface. The GPU then composes the surfaces and maps to provide the final image, which is delivered to its frame buffer.
Quartz Extreme only uses OpenGL commands, and requires a graphics card connected to an AGP
Accelerated Graphics Port
The Accelerated Graphics Port is a high-speed point-to-point channel for attaching a video card to a computer's motherboard, primarily to assist in the acceleration of 3D computer graphics. Since 2004 AGP has been progressively phased out in favor of PCI Express...
2X or faster bus (including AGP 4X, 8X, and PCI Express
PCI Express
PCI Express , officially abbreviated as PCIe, is a computer expansion card standard designed to replace the older PCI, PCI-X, and AGP bus standards...
), supporting textures and maps of arbitrary size, since many of the renderers have no size limitation (Quartz 2D for example). It is automatically enabled on Mac systems with one of the following types of graphics cards:
- AMD (ATI) RadeonRadeonRadeon is a brand of graphics processing units and random access memory produced by Advanced Micro Devices , first launched in 2000 by ATI Technologies, which was acquired by AMD in 2006. Radeon is the successor to the Rage line. There are four different groups, which can be differentiated by...
, AGP-based, 16MB VRAM minimum, or better - NVIDIA GeForce2 MX, 16MB VRAM minimum, or better
QuartzGL
QuartzGL (called Quartz 2D Extreme when it was introduced in Mac OS X Tiger) is GPU acceleration for the Quartz 2D API. As of Mac OS X Snow Leopard, it is still not enabled by default. However, it has been possible to enable it, using the Quartz Debug application included in the Apple Developer ToolsApple Developer Tools
The Apple Developer Tools are a suite of software tools from Apple to aid in making software titles for the Mac OS X platform. They come on the Snow Leopard installation CD as part of the Xcode suite, but aren't installed by default.- AppleScript Editor :...
. QuartzGL will be disabled once again upon quitting the Quartz Debug utility. A workaround is to force quit the Quartz Debug application, which will leave QuartzGL enabled system-wide.
All graphics cards capable of supporting Core Image
Core Image
Core Image is a pixel-accurate, near-realtime, non-destructive image processing technology in Mac OS X. Implemented as part of the QuartzCore framework of Mac OS X 10.4 and later, Core Image provides a plugin-based architecture for applying filters and effects within the Quartz graphics rendering...
also support QuartzGL.
As of August 2011, no non Apple web browser fully support GPU hardware acceleration based QuartzGL for rendering contents. Mac OS X 10.7, however, includes an edition of the Safari browser with full hardware acceleration support.
See also
- QuartzQuartz (graphics layer)Quartz specifically refers to a pair of Mac OS X technologies, each part of the Core Graphics framework: Quartz 2D and Quartz Compositor. It includes both a 2D renderer in Core Graphics and the composition engine that sends instructions to the graphics card...
- Quartz ComposerQuartz ComposerQuartz Composer is a node-based visual programming language provided as part of the Xcode development environment in Mac OS X for processing and rendering graphical data....
- Compositing window managerCompositing window managerA compositing window manager is a type of window manager. A window manager is software that draws a graphical user interface on a computer display – it positions windows, draws additional elements on windows , and controls how windows interact with each other, and with the rest of the desktop...
- X11
External links
- The Graphics and Windowing Environment - from Apple's Mac OS X Documentation
- Quartz Services Reference