GdkGCValues
for full
explanations of the arguments.gdkGCSetLineAttributes(object, line.width, line.style, cap.style, join.style)
line.width
line.style
GdkLineStyle
] the dash-style for lines.cap.style
GdkCapStyle
] the manner in which the ends of lines are drawn.join.style
GdkJoinStyle
] the in which lines are joined together.