arma3 rougher offroad driving script

// speed limit
if (hasinterface) then {
// if (false) then {

    // todo:
    // - Detect terrain / road
    // - Damage wheels based on speed
    // nearRoads
    // isOnRoad
    // getRoadinfo

    //

    player createDiaryRecord ["Diary", ["Rough Offroad Driving",
    "<font size='25'>Rogher offroad driving is active!</font><br/><font size='15'>Driving offroad will slow your car down."
    ]];

    ten_fnc_carSpeedLimit = {

        // discover the deltatime
        private _deltaTime = ((missionNamespace getVariable ['mission_carSpeedLimit_LastTime',cba_missiontime]) - cba_missiontime);
        missionNamespace setVariable ['mission_carSpeedLimit_LastTime', cba_missiontime];

        // only run on cars
        //if !((vehicle player) isKindOf 'Car') exitWith {};
        if !((vehicle player) isKindOf 'Land') exitWith {};

        // if ((isNull objectParent player ) && _killer isKindOf "CAManBase") then {
        if (isNull objectParent player ) exitWith {};


        private _vehicle = vehicle player;

        if (typeOf _vehicle isEqualTo 'B_Quadbike_01_F') exitWith {};

        private _s = speed _vehicle;

        private _o_Speed_Limit = 10;        // Above this km/h the vehicle speed is limited
        private _o_Speed_Min = 30;          // wheels start taking damage above this speed
        private _o_Speed_Max = 90;          // wheels take maximum damage at this speed
        if (typeOf _vehicle isEqualTo 'B_MRAP_01_F') then {
            _o_Speed_Limit = 50;
            _o_Speed_Limit = 60;
            _o_Speed_Limit = 120;
        };

        // speed must be bigger than 10
        if (_s < _o_Speed_Limit && (_s > -_o_Speed_Limit)) exitWith {};

        //private _v = velocityModelSpace _vehicle;
        //_v = (_v vectorAdd [0,0,0]);
        //_vehicle setVelocityModelSpace _v;
        //systemChat ("Speed: " + str _s);

        private _modifier = 0.05;
        private _modifierSpeed = 0.05;  // todo maker this based on  weight?

        // less effect when car is on road
        if (isOnRoad _vehicle) then {
            _modifier = 0.001;
            _modifierSpeed = 0.0025;  // TODO make this based on weight of vehicle


            _vehicle setVariable ['unit_carSpeedLimit_lastTimeOnroad', CBA_Missiontime];
        } else {
            // car is offroad

            _vehicle setVariable ['unit_carSpeedLimit_lastTimeOffroad', CBA_Missiontime];
        };

        private _timeSpentOffroad = CBA_Missiontime - (_vehicle getVariable ['unit_carSpeedLimit_lastTimeOnroad', 0]);
        private _timeSpentOffroadMod = linearConversion [0,3,_timeSpentOffroad,0,0.5,true];
        //_modifierSpeed = _modifierSpeed * _timeSpentOffroadMod;

        //systemChat ("Speed.ModifierSpeed:" + "____new____");
        //systemChat ("Speed.ModifierSpeed:" + str _modifierSpeed + " mod:" + str _timeSpentOffroadMod);

        private _timeSpentOnroad = CBA_Missiontime - (_vehicle getVariable ['unit_carSpeedLimit_lastTimeOffroad',0]);
        private _timeSpentOnroadMod = linearConversion [0,3,_timeSpentOnroad,0.5,0,true];
        //_modifierSpeed = _modifierSpeed * _timeSpentOnroadMod;

        //_modifierSpeed = _modifierSpeed * (_timeSpentOffroadMod + _timeSpentOnroadMod);
        _modifier = _modifier * (_timeSpentOffroadMod + _timeSpentOnroadMod);

        //systemChat ("Speed.ModifierSpeed:" + str _modifierSpeed + " mod:" + str _timeSpentOnroadMod);
        //systemChat ("Speed.Modifier:" + str _modifier);


        // damage car when speed is high
        if (_s > _o_Speed_Min || _s < -15) then {
            if (isOnRoad _vehicle) exitWith {};

            // damage car

            // increase modifier ?? (not)

            // check timer
            private _lastTime = _vehicle getVariable ['unit_carSpeedLimit_last', 0];
            if ((cba_missiontime - _lastTime) < 1) exitWith {};
            _vehicle setVariable ['unit_carSpeedLimit_last', cba_missiontime];

            // wheel_1_1_steering
            // wheel_1_2_steering
            // wheel_2_1_steering
            // wheel_2_2_steering
            call {

                // also increase the forceFront or speed, that way car slows more when this happens


                private _wheel = selectRandom ['wheel_1_1_steering','wheel_1_2_steering','wheel_2_1_steering','wheel_2_2_steering'];
                private _wheelDamage = _vehicle getHit _wheel;
                if (_wheelDamage >= 1) exitWith {};
                private _addedDamage = linearConversion [_o_Speed_Min,_o_Speed_Max,_s,0.0,0.1,true];
                _vehicle setHit [_wheel,(_wheelDamage + _addedDamage)];
                // systemChat str (_wheelDamage + _addedDamage);
            };
        };

        //_object = vehicle player;
        private _mass = getMass _vehicle;
        private _force = (_s * _modifier) * _mass;
        _force = _force * _deltaTime;
        if (_s <= 0) then {
            _force = 0 - (_force * 2);
        };
        private _forceFront = (_force * (_s * _modifierSpeed));
        //private _forceFront = 0 - (_force / _s);
        //systemChat str _forceFront;
        private _forceSide = _force * 10;        // from 10
        private _torque = _forceSide * 2;       // from 10
        //if (_s <= 0) then {
        //    _forceFront = -_forceFront;
        //    _forceSide = -_forceSide;
        //};

        // systemChat ("Speed.Side: " + str _forceSide);
        // systemChat ("Speed.Front: " + str _forceFront);

        _vehicle addForce [_vehicle vectorModelToWorld [(_forceSide - random(_forceSide * 2)),(_forceFront - random (_forceFront * 0.2)),0],[0,0,0]];
        _vehicle addTorque [(_torque - random(_torque * 2)),(_torque - random(_torque * 2)),0];

    };

    ten_carSpeedLimit_handle = [{[] call ten_fnc_carSpeedLimit}, 0] call CBA_fnc_addPerFrameHandler;
};