Abstract: The present invention provides a method and apparatus that permits the introduction of customized compositing techniques into an application by a developer. A Composite interface and a CompositeContext interface are defined. Custom compositing operations can be defined by implementing these interfaces. A Composite object provides a CompositeContext object that holds the state and performs the compositing work. Multiple CompositeContext objects can be created from one Composite object to maintain separate states in a multi-threaded environment. An object implementing the Composite interface can be set as rendering state on a graphics object that provides rendering methods. This allows arbitrary compositing rules to be used by a developer. In one implementation of the Composite and CompositeContext interfaces, an AlphaComposite class is defined.