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 endpoint.`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 width.`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 point.

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.