The arrow object has a straight box-shaped shaft with an arrowhead at one end. The following statement will display an arrow pointing parallel to the x axis:
The arrow object has attributes pos, x, y, z, axis, length, color, red, green, blue, and up like those for cylinders. The up attribute is significant for arrow because the shaft and head have square cross sections, and setting the up attribute rotates the arrow about its axis. Additional arrow attributes:
shaftwidth By default, shaftwidth = 0.1*(length of arrow)
headwidth By default, headwidth = 2*shaftwidth
headlength By default, headlength = 3*shaftwidth
Assigning any of these attributes to 0 makes it use defaults based on the size of the arrow. If headlength becomes larger than half the length of the arrow, or the shaft becomes thinner than 1/50 the length, the entire arrow is scaled accordingly.