ACE3/addons/common/functions/fnc_inWater.sqf

/**
 * fn_inWater_f.sqf
 * @Descr: Check if unit is underwater
 * @Author: Glowbal
 *
 * @Arguments: [unit OBJECT]
 * @Return: BOOL True if unit is in the water
 * @PublicAPI: true
 */

#include "script_component.hpp"

private ["_unit","_return","_aslPos"];
_unit = _this select 0;
_return = false;
if ((surfaceIsWater getPos _unit)) then {
    _aslPos = _unit modelToWorldVisual (_unit selectionPosition "head");
    if ((_aslPos select 2) <= 0) then {
        _return = true;
    };
};
_return;