Quartz is a powerful graphics system which forms the foundation of the imaging model for Mac OS X. Quartz offers a sophisticated two-dimensional drawing engine and an advanced windowing environment. Quartz's feature-rich drawing engine leverages the Portable Document Format (PDF) drawing model and offers Mac OS X applications professional-strength drawing functionality. Quartz's windowing services provide low-level functionality like window buffering, event handling/dispatch as well as dynamically creating the translucency and drop shadow effects found in the Aqua user interface.

Quartz Composer is a development tool provided with, and is the real star of, Mac OS X v10.4 Tiger (http://www.apple.com/macosx/overview/) for processing and rendering graphical data.

Quartz Composer is a OS level technology for motion graphics designed around OpenGL for real-time performances and high visual quality. It includes support for MIDI, QuickTime playback through Core Video, real-time Core Image filters, audio & video capture, external data sources like RSS feeds or Spotlight, simple JavaScripts and much more... It comes complete with a full-featured graphical editor:

QuartzComposer integrates OpenGL, CoreImage, CoreVideo, and other technologies into an API and a developer tool built around a simple visual programming paradigm for creating autonomous or interactive visual animations and explore the power of Tiger's graphic APIs without having to write a single line of code. 

I looked earlier this week at Quartz Composer, an interactive eye candy development tool that not only creates slick RSS newsfeed screensavers, but even allows audio and MIDI input and outputs MIDI control, perfect for live performance and VJing.

Developer Pierre-Olivier Latour has posted an extensive description of Quartz Composer at VJCentral. Quartz Composer is  a descendent of the now-defunct PixelShox, a free tool with a cult online following that is now unsupported. But there's no need to shed tears for PixelShox: Quartz Composer is a completely different product, a major leap forward taking advantage of OS X Tiger's new Core Image features.

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