# Turn proc (vector)

Source: https://ref.dm-lang.org/vector/proc/Turn
Added in BYOND 516.

### Format
- `A.Turn(angle)`
- `A.Turn(B)`


### Args
- `angle`: An angle to turn a vector clockwise in 2D.
- `B`: A vector to rotate around (right-hand rule).


### Returns
> The vector A, after rotating it.

This proc modifies the source vector. For legacy reasons, it rotates in the opposite direction of the built-in `turn()` proc.

All angles are in degrees.

When the argument is an angle, the source vector A is rotated in 2 dimensions clockwise.

When the argument is a vector, the source vector A is rotated in 3 dimensions around vector B using the right-hand rule (thumb pointed in the direction of B, rotation following curled fingers). The angle of rotation is the length of B, in degrees.

### See also
- [turn proc (applied to a vector)](https://ref.dm-lang.org/proc/turn/vector.md)
- [vector](https://ref.dm-lang.org/vector/index.md)
- [vector proc](https://ref.dm-lang.org/proc/vector.md)
- [vars (vector)](https://ref.dm-lang.org/vector/var/index.md)