ammoboxAction.sqf

#define CRATE_CLASSNAME "crate_classname_here"
#define CRATE_HEIGHT 100
#define CRATE_DISTANCE 15
#define CRATE_DIRECTION 0
#define MARKER_NAME "crate"
#define MARKER_ICON "hd_dot"

player addAction [
    "Spawn crate",
    {
        _position = player getRelPos [CRATE_DISTANCE,CRATE_DIRECTION];
        if (getMarkerPos MARKER_NAME isEqualTo [0,0,0]) then [{
            _marker = createMarker [MARKER_NAME,_position];
            _marker setMarkerShape "ICON";
            _marker setMarkerType MARKER_ICON;
        },{
            MARKER_NAME setMarkerPos _position;
        }];
        _position set [2,CRATE_HEIGHT];
        _crate = createVehicle[CRATE_CLASSNAME,_position,[],0,"NONE"]
        _crate attachTo [createVehicle ["B_parachute_02_F",_position,[],0,"CAN_COLLIDE"],[0,0,0]];
        ["AmmoboxInit",[_crate,true]] spawn BIS_fnc_arsenal;
    }
];