The display of lines when joining.
String value of this property
A join with a sharp, angled corner which is drawn with the outer sides beyond the endpoint of the path until they meet.
A join with a rounded end which is drawn beyond the endpoint of the line at a radius of one-half of the line's width and centered on the endpoint of the line.
A join with a squared-off end which is drawn beyond the endpoint of the line at a distance of one-half of the line's width.