Set turtle's move direction

setmovedir vector

Sets the new direction of a turtle's moves according to the vector specified as a 2-element array or list. This direction is used by the move instruction. Turtle's move direction is always a unit vector, however vector in the argument can be of any length.
Note: forward and back instructions change turtle's move direction to the current heading value.

Example:

repeat 8 [
  (print heading movedir)
  setmovedir array cos heading-90 cos heading
  move 30
  rt 45
]

Output:
(also a drawing)

0 {0 1}
45 {6.12303176911189E-17 1}
90 {0.707106781186548 0.707106781186548}
135 {1 6.12303176911189E-17}
180 {0.707106781186548 -0.707106781186547}
-135 {6.12303176911189E-17 -1}
-90 {-0.707106781186548 -0.707106781186547}
-45 {-1 6.12303176911189E-17}

See also:

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