NAME
    SetOPen -- Change the Area OutLine pen and turn on Outline
                    mode for areafills.
SYNOPSIS
    SetOPen(rp, pen)
    void SetOPen( struct rastport *, ubyte );
FUNCTION
    This is implemented as a c-macro.
    Pen is the pen number that will be used to draw a border
    around an areafill during areaend().
INPUTS
    rp = pointer to rastport structure
    pen = number  between 0-255
BUGS
SEE ALSO
    areaend() graphics/gfxmacros.h graphics/rastport.h