DrawPoly procedure

  DECLARATION:  DrawPoly(NumPoints : Word; var PolyPoints);

      PURPOSE:  Draws the outline of a polygon using the current
                line style and color.

         UNIT:  Graph

      REMARKS:  PolyPoints is an untyped parameter containing the
                coordinates of each intersection in the polygon.
                NumPoints contains the number of coordinates in PolyPoints
                A coordinate consists of two words, an X and a Y value.

                DrawPoly uses the current line style and color.
                Use SetWriteMode to determine whether the polygon copied
                to or XOR'd to the screen.

 RESTRICTIONS:  Must first be in graphics mode.

      EXAMPLE:  Uses
                   GRAPH;

                Const
                   Triangle: Array[1..4] of PointType = ((x:  50; y: 100),
                                                         (x: 100; y: 100),
                                                         (x: 150; y: 150),
                                                         (x:  50; y: 100));
                Var
                   Gd, Gm: Integer;

                Begin
                   Gd := Detect;
                   InitGraph(Gd, Gm, '');
                   If GraphResult <> grOK Then
                      Halt(1);
                   DrawPoly(SizeOf(Triangle) div SizeOf(PointType),Triangle);
                   ReadLn;
                   CloseGraph;
                End.