atan2: Difference between revisions

Revision as of 16:33, 28 June 2014

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Description:: ArcTangent of x/y. Used to determine the angle of a vector [x,y]. Result in Degrees.
Note that this command can handle y being 0, unlike when using atan, and will return 90
Groups:: Uncategorised

Example 1:: _xy = [5,3]; _degrees = (_xy select 0) atan2 (_xy 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 if (_dir < 0) then {_dir = 360 + _dir}; //_dir range from 0 to 360

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Only post proven facts here! Add Note

Posted on 08:00, 18 November 2009
KeV: To get the direction of an object from the player: _dir = ((getPos _obj select 0) - (getPos player select 0)) atan2 ((getPos _obj select 1) - (getPos player select 1)); //_dir will be from -180 to 180. If positive values are needed then use: if (_dir < 0) then {_dir = _dir + 360}; Or just use BIS_fnc_dirTo directly.

@@ Line 39: / Line 39: @@
 <dl class="command_description">
 <!-- Note Section BEGIN -->
-To get the direction of an object from the player: <br>
+<dd class="notedate">Posted on 08:00, 18 November 2009
-_direction = ((getpos object select 0) - (getpos player select 0)) atan2 ((getpos object select 1) - (getpos player select 1)); <br>
+<dt class="note">'''[[User:KeV|KeV]]'''<dd class="note">
-_direction will be from -180 to 180 <br>
+To get the direction of an object from the player:
-If positive values are needed then use:<br>
+<code>
-if(_direction < 0) then {_direction = _direction + 360};
+_dir = (([[getPos]] _obj [[select]] 0) - ([[getPos]] [[player]] [[select]] 0)) [[atan2]] (([[getPos]] _obj [[select]] 1) - ([[getPos]] [[player]] [[select]] 1));
+//_dir will be from -180 to 180.
+</code>
+If positive values are needed then use:
+<code>
+[[if]] (_dir < 0) [[then]] {_dir = _dir + 360};
+</code>
+Or just use [[BIS_fnc_dirTo]] directly.
 <!-- Note Section END -->
 </dl>