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8.12. Canvas polygon objects

As displayed, a polygon has two parts: its outline and its interior. Its geometry is specified as a series of vertices [(x0, y0), (x1, y1), … (xn, yn)], but the actual perimeter includes one more segment from (xn, yn) back to (x0, y0). In this example, there are five vertices:

To create a new polygon object on a canvas C:

    id = C.create_polygon(x0, y0, x1, y1, ..., option, ...)

The constructor returns the object ID for that object. Options:

Table 12. Canvas polygon options

activedash These options specify the appearance of the polygon when it is in the tk.ACTIVE state, that is, when the mouse is over it. For option values, see dash, fill, outline, outlinestipple, stipple, and width.
dash Use this option to produce a dashed border around the polygon. See Section 5.13, “Dash patterns”.
dashoffset Use this option to start the dash pattern at some point in its cycle other than the beginning. See Section 5.13, “Dash patterns”.
disableddash These options specify the appearance of the polygon when its state is tk.DISABLED.
fill You can color the interior by setting this option to a color. The default appearance for the interior of a polygon is transparent, and you can set fill='' to get this behavior. See Section 5.3, “Colors”.
joinstyle This option controls the appearance of the intersections between adjacent sides of the polygon. See Section 5.12, “Cap and join styles”.
offset Offset of the stipple pattern in the interior of the polygon. See Section 5.14, “Matching stipple patterns”.
outline Color of the outline; defaults to outline='', which makes the outline transparent.
outlineoffset Stipple offset for the border. See Section 5.14, “Matching stipple patterns”.
outlinestipple Use this option to get a stippled border around the polygon. The option value must be a bitmap; see Section 5.7, “Bitmaps”.
smooth The default outline uses straight lines to connect the vertices; use smooth=0 to get that behavior. If you use smooth=1, you get a continuous spline curve. Moreover, if you set smooth=1, you can make any segment straight by duplicating the coordinates at each end of that segment.
splinesteps If the smooth option is true, each spline is rendered as a number of straight line segments. The splinesteps option specifies the number of segments used to approximate each section of the line; the default is splinesteps=12.
state By default, polygons are created in the tk.NORMAL state. Set this option to tk.HIDDEN to make the polygon invisible, or set it to tk.DISABLED to make it unresponsive to the mouse.
stipple A bitmap indicating how the interior of the polygon will be stippled. Default is stipple='', which means a solid color. A typical value would be stipple='gray25'. Has no effect unless the fill has been set to some color. See Section 5.7, “Bitmaps”.
tags If a single string, the polygon is tagged with that string. Use a tuple of strings to tag the polygon with multiple tags. See Section 8.4, “Canvas tags”.
width Width of the outline; defaults to 1. See Section 5.1, “Dimensions”.