PRE
></TD
></TR
></TABLE
><P
>Add the line (<TT
CLASS="PARAMETER"
><I
>x0</I
></TT
>, <TT
CLASS="PARAMETER"
><I
>y0</I
></TT
>) - (<TT
CLASS="PARAMETER"
><I
>x1</I
></TT
>, <TT
CLASS="PARAMETER"
><I
>y1</I
></TT
>) to <TT
CLASS="PARAMETER"
><I
>uta</I
></TT
>, and also update the
winding number buffer used for rendering the interior. <TT
CLASS="PARAMETER"
><I
>rbuf</I
></TT
>
contains the first partial difference (in the X direction) of the
winding number, measured in grid cells. Thus, each time that a line