This is an unofficial mirror of Tkinter reference documentation (based on Python 2.7 and Tk 8.5) created by the late John Shipman.
It was last updated in 2013 and is unmaintained. [More info]
For pleasant and effective rendering of diagrams, sometimes it is a good idea to pay attention to cap and join styles.
The cap style of a line is the shape of the end of the line. Styles are:
tk.BUTT: The end of the line is cut
off square at a line that passes through the
tk.PROJECTING: The end of the line is
cut off square, but the cut line projects past
the endpoint a distance equal to half the line's
tk.ROUND: The end describes a
semicircle centered on the endpoint.
The join style describes the shape where two line segments meet at an angle.
tk.ROUND: The join is a circle
centered on the point where the adjacent
line segments meet.
tk.BEVEL: A flat facet is drawn
at an angle intermediate between the angles
of the adjacent lines.
tk.MITER: The edges of the adjacent
line segments are continued to meet at a sharp
This illustration shows how Tkinter's cap and join options work with a line made of two connected line segments. Small red circles show the location of the points that define this line.