atan2

Description

ArcTangent of y/x. Used to determine the angle of a vector [y,x]. Result in Degrees between -180 and 180.

Note
This command can handle x being 0, unlike when using atan, and will return 90

Important
This command has higher precedence than the select command, therefore beware of the case below:
 _pos select 0  atan2 (_pos select 1) // error
(_pos select 0) atan2 (_pos select 1) // OK
Alternatively, consider using the # operator: _pos # 0 atan2 _pos # 1

Syntax

y atan2 x

Parameters:

y: Number
x: Number

Returns: Number

Examples

Example 1

_yx = [5,3];
_degrees = (_yx select 0) atan2 (_yx select 1); // 59.0362

Example 2

Get direction from _obj1 to _obj2:

_vd = getPosASL _obj2 vectorDiff getPosASL _obj1;
_dir = (_vd select 0) atan2 (_vd select 1); // _dir range from -180 to +180
_dir = (_dir + 360) % 360; // _dir range from 0 to 360

Example 3

Get relative direction from _obj1 to _obj2:

_yx = _obj1 worldToModel getPosASL _obj2;
_dir = (_yx select 0) atan2 (_yx select 1); // _dir range from -180 to +180
_dir = (_dir + 360) % 360; // _dir range from 0 to 360