1. An electronic circuit for generating a screen display, the screen display comprising a plurality of windows, the windows having been ordered in accordance with a predetermined display priority, each of said windows comprising a plurality of pixels, each pixel associated with a location in the screen display, the circuit comprising: a plurality of circuit means for detecting whether a corresponding one of said windows includes a pixel associated with a given location in the screen display; a plurality of transparency detector circuits, each transparency detector circuit electrically coupled to a corresponding one of said circuit means for detecting whether the corresponding window includes a pixel associated with the given location in the screen display, each of said transparency detector circuits operable to detect whether the pixel in the corresponding window associated with the given location in the screen display has been coded as a transparent pixel; a priority encoder circuit electrically coupled to each of said transparency detector circuits, wherein the priority encoder circuit generates a signal representing one of said windows, said represented window having a higher display priority than any other of said windows which includes a pixel associated with the given location in the screen display which has not been coded as a transparent pixel; and a signal generating means, electrically coupled to said priority encoder circuit, for generating a signal representing the pixel in the represented window associated with the given location in the screen display.