Copyright © 2007-2009 by Apple Inc.  All Rights Reserved.
Quartz Composer Application
OverlayComposition              A background only application that renders a Quartz 
                        Composition in a floating transparent window on top 
                        of the desktop, and which only updates at a specified 
Sample Requirements             The project was created using the Xcode running under 
                        Mac OS X 10.6.x or later. The supplied Quartz Composer 
                        compositions were created using the Quartz Composer 
                        editor running under Mac OS X 10.6.x or later.
About the sample                This sample shows how to render a composition with 
                        QCRenderer in a QCView. At the beginning, the sample 
                        renders a default composition. Ctl-click on the 
                        window, a pop menu will show, the user can change the 
                        composition name, parameters of the composition or the 
                        rendering dimensions. The rendering window is a QCView, 
                        it receives the mouse events and passes them to the 
                        application. The application handles the menu. When the 
                        use selects an item from the menu, the application 
                        responds accordingly.
Using the Sample                Open the project using the Xcode editor which can be 
                        found in /Developer/Applications. Build the project and 
                        run. Ctl-click on the window to pop up the menu. Change 
                        the parameters to see different results.
Installation                    n/a
Changes from Previous Versions          n/a
Feedback and Bug Reports            Please send all feedback about this sample to:
                        Please submit any bug reports about this example to