draw_polygon

#Draw.Polygon

##Syntax Draw.Polygon (x, y : array 1 .. * of int, n : int, Color : int)

##Description The Draw.Polygon procedure is used to draw a polygon with n points. A line is drawn in Color from the point (x(1), y(1)) to (x(2), y(2)) to (x(3), y(3)) and so on. After drawing the line to (x(n), y (n)), a line will be drawn back to (x(1), y(1)), closing the polygon. The Draw.Polygon procedure is equivalent to:

    for i : 1 .. n - 1
        Draw.Line (x (i), y(i), x (i + 1), y (i + 1), Color)
    end for
    Draw.Line (x (n), y (n), x (1), y (1), Color)

##Example This program will create an octagon and display it in color 1.

    View.Set ("graphics")
    var x : array 1..8 of int := init (100, 100, 135, 185, 
                               220, 220, 185, 135)
    var y : array 1..8 of int := init (100, 150, 185, 185,
                               150, 100, 65, 65)
    Draw.Polygon (x, y, 8, brightblue)

##Details The IBM PC limits Draw.Polygon to a maximum of 256 points.

The screen must be in a "graphics" mode. See the View.Set procedure for details. If the screen is not in a "graphics" mode, an error will occur.

##Status Exported qualified.

This means that you can only call the function by calling Draw.Polygon, not by calling Polygon.

##See also view_set.html, maxx.html, maxy.html and the various procedures in the drawmodule.html unit.