Abstract: A compositing architecture provides for correct rendering of overlapping opaque and translucent regions of respective graphic images with rapid pixel restoration when an image floating above another image is moved or manipulated to reveal pixels of a graphic image at a greater depth by provision for buffering data corresponding to a portion of a graphic image which is beneath another graphic image. Data representing graphic images is selectively routed to a painter in response to a determination of opacity and depth order of the graphic images. A plurality of painters are preferably provided with image rendering pipeline of differing lengths. A painter is chosen in accordance with the number of images to be composited. Data buffering is minimized by dynamic creation and removal of buffers in accordance with the intersecting regions of the graphic images.

Abstract: A video framework for use in a data processing system provides parallel hierarchies of video device drivers and video device handles, which are created by video device driver objects, and a hierarchy of data encapsulators contained by a subclass of the hierarchy of video device handles to encapsulate configuration information describing the functionality of a display device connected to a data processing system. Applications access video device drivers through ones of the video device handles at respective levels of the video device handle hierarchy. When a change of configuration is made or requested in for the data processing system or any display connected thereto, corresponding video display handles issue a signal to lock down drawing tasks before video handles are created or altered to carry out the configuration change.