This part of ISO/IEC 9636 describes those functions of the Computer Graphics Interface concerned with creating, modifying, retrieving, and displaying portions of an image stored as pixel data. It includes functionality for combining such images. This part of ISO/IEC 9636 is part 6 of ISO/IEC 9636 and should be read in conjunction with ISO/IEC 9636-1, ISO/IEC 9636-2, and ISO/IEC 9636-3. The relationship of this part of ISO/IEC 9636 to the other parts of ISO/IEC 9636 is described in ISO/IEC 9636-1 (see ISO/IEC 9636-1,5.2.1 and figures 6 and 7) and in clause 4. The functionality described in this part of ISO/IEC 9636 pertains to Virtual Devices of class OUTPUT and OUTIN with display type RASTER.