A system for displaying motion video objects on a display screen together with other visual objects such as bit map image objects, text objects, and the like. An autonomous screen drawing process is provided whereby the motion video object is displayed directly to the screen through a clipmask. When a screen update is needed because of changes in the appearance of one of the objects on the screen, for example, by changing the size, shape or location of one the objects, the autonomous drawing process is stopped. The visual objects and the motion video objects are redrawn to the screen (or to a frame composition memory from which the screen is copied), and for each motion video object a clipmask is initialized in the location and shape of the motion video object. Every other object which overlaps the motion video object leaves its footprint on the clipmask. When all objects have been redrawn, the autonomous drawing process is restarted using the newly-derived clipmask.