Quartz Composer

The QCComposition class represents a Quartz Composer composition that either:

A layer that loads, plays, and controls Quartz Composer compositions in a Core Animation layer hierarchy.

A class that allows users to edit the input parameters of a composition in real time. The composition can be rendering in any of the following objects: QCRenderer, QCView, or QCCompositionLayer.

The QCCompositionPickerPanel class represents a utility window that allows users to browse compositions that are in the Quartz Composer composition repository and, if supported, preview the composition. The QCCompositionPickerPanel class cannot be subclassed.

The QCCompositionPickerView class allows users to browse compositions that are in the Quartz Composer composition repository, and to preview them. You can set the default input parameters for a composition preview by using the method setDefaultValue:forInputKey:.

The QCCompositionRepository class represents a system-wide centralized repository of built-in and installed Quartz Composer compositions (/Library/Compositions and ~/Library/Compositions). The QCCompositionRepository class cannot be subclassed.

The QCPlugIn class provides the base class to subclass for writing custom Quartz Composer patches. You implement a custom patch by subclassing QCPlugIn, overriding the appropriate methods, packaging the code as an NSBundle object, and installing the bundle in the appropriate location. A bundle can contain more than one subclass of QCPlugIn, allowing you to provide a suite of custom patches in one bundle. Quartz Composer Custom Patch Programming Guide provides detailed instructions on how to create and package a custom patch. QCPlugIn Class Reference supplements the information in the programming guide.

The QCPlugInViewController class communicates (through Cocoa bindings) between a custom patch and the view used for the internal settings of the custom patch. Only custom patches that use internal settings exposed to the user need to use the QCPlugInViewController class.

A QCRenderer class is designed for low-level rendering of Quartz Composer compositions. This is the class to use if you want to be in charge of rendering a composition to a specific OpenGL context—either using the NSOpenGLContext class or a CGLContextObj object. QCRenderer also allows you to load, play, and control a composition.

The QCView class is a custom NSView class that loads, plays, and controls Quartz Composer compositions. It is an autonomous view that is driven by an internal timer running on the main thread.

The QCCompositionParameterViewDelegate informal protocol allows your application to define which parameters should be visible in a QCCompositionParameterView object.

The QCCompositionPickerViewDelegate informal protocol defines methods that allow your application to respond to changes in a composition picker view (a QCCompositionPickerView object).

The QCRenderer protocol defines the methods used to pass data to the input ports or retrieve data from the output ports of the root patch of a Quartz Composer composition. This protocol is adopted by the QCRenderer, QCView, and QCCompositionLayer classes.

The QCPlugInContext protocol defines methods that you use only from within the execution method (execute(_:atTime:withArguments:)) of a QCPlugIn object.

The QCPlugInInputImageSource protocol eliminates the need to use explicit image types for the image input ports on your custom patch. Not only does using the protocol avoid restrictions of a specific image type, but it avoids impedance mismatches, and provides better performance by deferring pixel computation until it is needed. When you need to access the pixels in an image, you simply convert the image to a representation (texture or buffer) using one of the methods defined by the QCPlugInInputImageSource protocol. Use a texture representation when you want to use input images on the GPU. Use a buffer representation when you want to use input images on the CPU.

The QCPlugInOuputImageProvider protocol eliminates the need to use explicit image types for the image output ports on a custom patch. The methods in this protocol are called by the Quartz Composer engine when the output image is needed. If your custom patch has an image output port, you need to implement the appropriate methods for rendering image data and to supply information about the rendering destination and the image bounds.

Execution modes for custom patches.

Time modes for custom patches.