NAME
        ClearScreen -- Clear from current position to end of rastport.

   SYNOPSIS
        ClearScreen(rp)
                    A1

        void ClearScreen(struct rastport *);

   FUNCTION
        Clear a rectangular swath from the current position to the
        right edge of the rastPort with cleareol, then clear the rest
        of the screen from just beneath the swath to the bottom of
        the rastPort.
        Clearing consists of setting the color of the swath to zero,
        or, if the DrawMode is 2, to the BgPen.

   INPUTS
        rp - pointer to rastport structure

   NOTES
        o   This function may use the blitter.

   SEE ALSO
        cleareol()  text()  setrast()
        graphics/text.h  graphics/rastport.h