NAME
    AreaEllipse -- add a ellipse to areainfo list for areafill.


SYNOPSIS
    error = AreaEllipse( rp, cx,   cy,   a,    b    )
    d0                   a1  d0:16 d1:16 d2:16 d3:16

    LONG AreaEllipse( struct rastport *, short, short, short, short)

FUNCTION
    Add an ellipse to the vector buffer. It will be draw when areaend() is
    called.

INPUTS
    rp - pointer to a rastport structure
    cx - x coordinate of the centerpoint relative to the rastport.
    cy - y coordinate of the centerpoint relative to the rastport.
    a  - the horizontal radius of the ellipse (note: a must be > 0)
    b  - the vertical radius of the ellipse (note: b must be > 0)

RESULT
    error - zero for success, or -1 if there is no space left in the
            vector list

SEE ALSO
    areamove() areadraw() areacircle() initarea() areaend()
    graphics/rastport.h