roll

roll

This is a built-in turtle variable. Roll is the angle between the “wing-tip” of the turtle and the xy-plane.

This is a number greater than or equal to 0 and less than 360. You can set this variable to make a turtle roll. Since roll is always from the turtle’s point of view, rolling right and left only only change roll regardless of turtle orientation.

Example:

set roll 45      ;; turtle rotated right
set roll roll + 10 ;; same effect as "roll-right 10"

See also heading, pitch, roll-left, roll-right.