Basic Motorcycle script

// :CATEGORY:Positioning
// :NAME:Car
// :AUTHOR:Anonymous
// :CREATED:2010-01-10 05:20:56.000
// :EDITED:2013-09-18 15:38:50
// :ID:151
// :NUM:219
// :REV:1.0
// :WORLD:Second Life
// :DESCRIPTION:
// Car.lsl
// :CODE:

//Basic Motorcycle Script
//
// by Cory
// commented by Ben

//The new vehicle action allows us to make any physical object in Second Life a vehicle. This script is a good example of a
// very basic vehicle that is done very well.

integer loopsnd = 0;

default
{

    //There are several things that we need to do to define vehicle, and how the user interacts with it.  It makes sense to
    // do this right away, in state_entry.
    state_entry()
    {

        //We can change the text in the pie menu to more accurately reflecet the situation.  The default text is "Sit" but in
        // some instances we want you to know you can drive or ride a vehicle by sitting on it. The llSetSitText function will
        // do this.
        llSetSitText("Drive");

        //Since you want this to be ridden, we need to make sure that the avatar "rides" it in a acceptable position
        // and the camera allows the driver to see what is going on.
        //
        //llSitTarget is a new function that lets us define how an avatar will orient itself when sitting.
        // The vector is the offset that your avatar's center will be from the parent object's center.  The
        // rotation is bassed off the positive x axis of the parent. For this motorcycle, we need you to sit in a way
        // that looks right with the motorcycle sit animation, so we have your avatar sit slightly offset from the seat.
        llSitTarget(<0.3, 0.0, 0.55>, ZERO_ROTATION);

        //To set the camera, we need to set where the camera is, and what it is looking at.  By default, it will
        // be looking at your avatar's torso, from a position above and behind. It will also be free to rotate around your
        // avatar when "turning."
        //
        //For the motorcycle, we are going to set the camera to be behind the cycle, looking at a point in front of it.
        // Due to the orientation of the parent object, this will appear to be looking down on the avatar as they navigate
        // course.
        llSetCameraEyeOffset(<-5.0, -0.00, 2.0>);
        llSetCameraAtOffset(<3.0, 0.0, 2.0>);

        //Ask cory "why?"
        llSetVehicleFlags(-1);

        //To make an object a vehicle, we need to define it as a vehicle.  This is done by assigning it a vehicle type.
        // A vehicle type is a predefined set of paramaeters that describe how the physics engine should let your
        // object move. If the type is set to VEHICLE_TYPE_NONE it will no longer be a vehicle.
        //
        //The motorcycle uses the car type on the assumption that this will be the closest to how a motorcycle should work.
        // Any type could be used, and all the parameters redefined later.
        llSetVehicleType(VEHICLE_TYPE_CAR);


        //While the type defines all the parameters, a motorcycle is not a car, so we need to change some parameters
        // to make it behave correctly.

        //The vehicle flags let us set specific behaviors for a vehicle that would not be covered by the more general
        // parameters. <more needed>
        llSetVehicleFlags(VEHICLE_FLAG_NO_FLY_UP | VEHICLE_FLAG_LIMIT_ROLL_ONLY);

        //To redefine parameters, we use the function llSetVehicleHippoParam where Hippo is the variable type of the
        // parameter (float, vector, or rotation).
        //
        //Most parameters come in pairs, and efficiency and a timescale. The efficiency defines <more>, while the timescale
        // defines the time it takes to achive that effect.
        //
        //In a virtual world, a motorcycle is a motorcycle because it looks and moves like a motorcycle.  The look is
        // up to the artist who creates the model.  We get to define how it moves.  The most basic properties of movement
        // can be thought of as the angular deflection (points in the way it moves) and the linear deflection (moves in the
        // way it points).  A dart would have a high angular deflection, and a low linear deflection.  A motorcycle has
        // a low linear deflection and a high linear deflection, it goes where the wheels send it. The timescales for these
        // behaviors are kept pretty short.
        llSetVehicleFloatParam(VEHICLE_ANGULAR_DEFLECTION_EFFICIENCY, 0.2);
        llSetVehicleFloatParam(VEHICLE_LINEAR_DEFLECTION_EFFICIENCY, 0.80);
        llSetVehicleFloatParam(VEHICLE_ANGULAR_DEFLECTION_TIMESCALE, 0.10);
        llSetVehicleFloatParam(VEHICLE_LINEAR_DEFLECTION_TIMESCALE, 0.10);

        //A bobsled could get by without anything making it go or turn except for a icey hill. A motorcycle, however, has
        // a motor and can be steered.  In LSL, these are linear and angular motors.  The linear motor is a push, the angular
        // motor is a twist.  We apply these motors when we use the controls, but there is some set up to do.  The motor
        // timescale controls how long it takes to get the full effect  of the motor, basically acceleration. The motor decay
        // timescale defines how long the motor stays at that strength - how slowly you let off the gas pedal.
        llSetVehicleFloatParam(VEHICLE_LINEAR_MOTOR_TIMESCALE, 0.3);
        llSetVehicleFloatParam(VEHICLE_LINEAR_MOTOR_DECAY_TIMESCALE, 0.2);
        llSetVehicleFloatParam(VEHICLE_ANGULAR_MOTOR_TIMESCALE, 0.3);
        llSetVehicleFloatParam(VEHICLE_ANGULAR_MOTOR_DECAY_TIMESCALE, 0.1);

        //<wait for andrew's changes>
        llSetVehicleVectorParam(VEHICLE_LINEAR_FRICTION_TIMESCALE, <1000.0, 2.0, 1000.0>);
        llSetVehicleVectorParam(VEHICLE_ANGULAR_FRICTION_TIMESCALE, <10.0, 10.0, 1000.0>);

        //We are using a couple of tricks to make the motorcycle look like a real motorcycle.  We use an animated texture to
        // spin the wheels.  The actual object can not rely on the real world physics that lets a motorcycle stay upright.
        // We use the vertical attractor parameter to make the object try to stay upright. The vertical attractor also allows
        // us to make the vehicle bank, or lean into turns.
        //
        //<NOT SURE IF FOLLOWING IS RIGHT>
        //The vertical attaction efficiency is slightly missnamed, as it should be "coefficient." Basically, it controls
        // if we critically damp to vertical, or "wobble" more.  The timescale will control how fast we go back to vertical, and
        // thus how strong the vertical attractor is.
        //
        //We want people to be able to lean into turns,<ugh>
        llSetVehicleFloatParam(VEHICLE_VERTICAL_ATTRACTION_EFFICIENCY, 0.90);
        llSetVehicleFloatParam(VEHICLE_VERTICAL_ATTRACTION_TIMESCALE, 0.90);

        //Banking means that if we rotate on the roll axis, we will also rotate on the yaw axis, meaning that our motorcycle will lean to the
        // side as we turn. Not only is this one of the things that make it look like a real motorcycle, it makes it look really cool too. The
        // higher the banking efficiency, the more "turn" for your "lean".  This motorcycle is made to be pretty responsive, so we have a high
        // efficiency and a very low timescale.
        llSetVehicleFloatParam(VEHICLE_BANKING_EFFICIENCY, 0.05);
        llSetVehicleFloatParam(VEHICLE_BANKING_TIMESCALE, 0.1);

        llCollisionSound("", 0.0);
    }


    //A sitting avatar is treated like a extra linked primitive, which means that we can capture when someone sits on the
    // vehicle by looking for the changed event, specifically, a link change.
    changed(integer change)
    {
        //Make sure that the change is a link, so most likely to be a sitting avatar.
        if (change & CHANGED_LINK)
        {
            //The llAvatarSitOnTarget function will let us find the key of an avatar that sits on an object using llSitTarget
            // which we defined in the state_entry event. We can use this to make sure that only the owner can drive our vehicle.
            // We can also use this to find if the avatar is sitting, or is getting up, because both will be a link change.
            // If the avatar is sitting down, it will return its key, otherwise it will return a null key when it stands up.
            key agent = llAvatarOnSitTarget();

            //If sitting down.
            if (agent)
            {
                //We don't want random punks to come stealing our motorcycle! The simple solution is to unsit them,
                // and for kicks, send um flying.
                if (agent != llGetOwner())
                {
                    llSay(0, "You aren't the owner");
                    llUnSit(agent);
                    llPushObject(agent, <0,0,100>, ZERO_VECTOR, FALSE);
                }
                // If you are the owner, lets ride!
                else
                {
                    //The vehicle works with the physics engine, so in order for a object to act like a vehicle, it must first be
                    // set physical.
                    llSetStatus(STATUS_PHYSICS, TRUE);
                    //There is an assumption that if you are going to choose to sit on a vehicle, you are implicitly giving
                    // permission to let that vehicle act on your controls, and to set your permissions, so the end user
                    // is no longer asked for permission.  However, you still need to request these permissions, so all the
                    // paperwork is filed.
                    llRequestPermissions(agent, PERMISSION_TRIGGER_ANIMATION | PERMISSION_TAKE_CONTROLS);
                }
            }
            //The null key has been returned, so no one is driving anymore.
            else
            {
                //Clean up everything.  Set things nonphysical so they don't slow down the simulator.  Release controls so the
                // avatar move, and stop forcing the animations.
                llSetStatus(STATUS_PHYSICS, FALSE);
                llReleaseControls();
                llStopAnimation("sit");
            }
        }

    }

    //Because we still need to request permissions, the run_time_permissions event still occurs, and is the perfect place to start
    // the sitting animation and take controls.
    run_time_permissions(integer perm)
    {
        if (perm)
        {
            llStartAnimation("sit");
            llTakeControls(CONTROL_FWD | CONTROL_BACK | CONTROL_RIGHT | CONTROL_LEFT | CONTROL_ROT_RIGHT | CONTROL_ROT_LEFT, TRUE, FALSE);
        }
    }

    //If we want to drive this motorcycle, we need to use the controls.
    control(key id, integer level, integer edge)
    {
        //We will apply motors according to what control is used.  For forward and back, a linear motor is applied with a vector
        // parameter.
        vector angular_motor;

        if (level & edge & CONTROL_FWD)
        {
            // Forward key was initially pressed
            llSetVehicleVectorParam(VEHICLE_LINEAR_MOTOR_DIRECTION, <50,0,0>);

        }
        else if ((edge & CONTROL_FWD) && ((level & CONTROL_FWD) == FALSE))
        {
            // Forward key was just released
            llSetVehicleVectorParam(VEHICLE_LINEAR_MOTOR_DIRECTION, <0,0,0>);

            loopsnd = 0;
        }
        else if (level & CONTROL_FWD)
        {
            // Forward key was just released
            llSetVehicleVectorParam(VEHICLE_LINEAR_MOTOR_DIRECTION, <50,0,0>);


        }

        if(level & CONTROL_BACK)
        {
            llSetVehicleVectorParam(VEHICLE_LINEAR_MOTOR_DIRECTION, <-10,0,0>);
        }
        if(level & (CONTROL_RIGHT|CONTROL_ROT_RIGHT))
        {
            angular_motor.x += 100;
            angular_motor.z -= 100;
        }
        if(level & (CONTROL_LEFT|CONTROL_ROT_LEFT))
        {
            angular_motor.x -= 100;
            angular_motor.z += 100;
        }
        if(level & (CONTROL_UP))
        {
            angular_motor.y -= 50;
        }

        llSetVehicleVectorParam(VEHICLE_ANGULAR_MOTOR_DIRECTION, angular_motor);
    }

}
// END //