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KShip

Well this is basically my code for a space ship, thanks a lot to Daid for lending me his replication code (which turned out to come from KCar but i thank him non the less, great guy he is :D)

I currently use a different, more client oriented replication system, but this one here is a lot better, i havent incorporated my ship to it yet because i have some other problems that come with it that i have to solve, but since the "core" ship here is simple, ill use the better replication for you guys :)

(Btw i deal with all the entering/leaving of the vehicle in a parent class, this is really irrelevant to physics and is easy to do, so i left it out just so there will be less and easier to read code)

var float           Roll, CThrust, TempThrust, OldThrust; 
// Throttle and Steering are already declared in KVehicle, so all we need is roll, CThrust, TempThrust, OldThrust will be explained soon
// BTW note that i use Throttle for Pitch alteration because it is already bound by other vehicles to the forward/backward key
// ok i have also incorporated a system that allows for various thrust managments, 
//if you simply want to move forward full speed only while you press the the thrust button, you would use TempThrust. 
//when you release the thrust button you though you should always set TempThrust to -1
// if you want to have a constant speed, assign it to CThrust, so every time you release the thrust button (the one that changes TempThrust) 
// you would automatically start going at that speed (good for stuff like dogifghting and matching speeds)
// and lastly i added an afterburner effect, ill include it here for you guys to see although it isnt hard to do.
// also what i did with it was that when you afterburn and you run out of energy, while you still hold the afterburn key
// you would keep going at your max possible speed, and once you release it you would start going at your constant wanted speed (CThrust)
// Thats why i have 2 vars, bAfterburn is for after burning (holding key and having enough E), bBurn is for only holding the afterburn key with no regard to its depletion
var bool            bAfterburn, bBurn; // note that you should set both of those to true when you want to afterburn
var() float         ForwardTrust, TurnRate, AfterBurnThrust; // This is basically how fast our ship turns/moves
var float           CurRoll, CurSteering, CurThrottle, UnitAccRate; // This is used for acceleration
// CThrust is used for ships that can assign a specific throttle value, like 75% of max speed or whatever...
// UnitAccRate is how much each value increases per second
var vector          ExtraForce, ExtraTorque; // Used for Karama forces pileup

// Ship replication vars and functions, thanks daid!
struct StructShipState
{
    var KRBVec              ChassisPosition;
    var Quat                ChassisQuaternion;
    var KRBVec              ChassisLinVel;
    var KRBVec              ChassisAngVel;

    var float               ServerSteering;
    var float               ServerThrottle;
    var float               ServerRoll;

    var bool                ServerbAfterburn;
    var bool                ServerbBurn;

    var bool                bNewState; // Set to true whenever a new state is received and should be processed
};

var KRigidBodyState     ChassisState;

var StructShipState     ShipState; // This is replicated to the ship, and processed to update all the parts.
var bool            bNewShipState; // Indicated there is new data processed, and chassis RBState should be updated.

var float           NextNetUpdateTime;  // Next time we should force an update of vehicles state.
var() float         MaxNetUpdateInterval;

var int AVar;//Just for replication, else the ShipState doesn't get replicated

Replication
{
    unreliable if(Role == ROLE_Authority)
        ShipState, AVar;
}

simulated event VehicleStateReceived()
{
    if(!ShipState.bNewState)
        return;

    // Get root chassis info
    ChassisState.Position = ShipState.ChassisPosition;
    ChassisState.Quaternion = ShipState.ChassisQuaternion;
    ChassisState.LinVel = ShipState.ChassisLinVel;
    ChassisState.AngVel = ShipState.ChassisAngVel;

    // Update control inputs
    Steering = ShipState.ServerSteering;
    Throttle = ShipState.ServerThrottle;
    Roll = ShipState.ServerRoll;

    // Afterburner
    bAfterburn = ShipState.ServerbAfterburn;
    bBurn = ShipState.ServerbBurn;

    // Update flags
    ShipState.bNewState = false;
    bNewShipState = true;
}

simulated event bool KUpdateState(out KRigidBodyState newState)
{
    // This should never get called on the server - but just in case!
    if(Role == ROLE_Authority || !bNewShipState)
        return false;

    // Apply received data as new position of ship chassis.
    newState = ChassisState;
    bNewShipState = false;

    return true;
}

function PackState()
{
    local vector chassisPos, chassisLinVel, chassisAngVel;
    local vector oldPos, oldLinVel;
    local KRigidBodyState ChassisState;

    // Get chassis state.
    KGetRigidBodyState(ChassisState);

    chassisPos = KRBVecToVector(ChassisState.Position);
    chassisLinVel = KRBVecToVector(ChassisState.LinVel);
    chassisAngVel = KRBVecToVector(ChassisState.AngVel);

    // Last position we sent
    oldPos = KRBVectoVector(ShipState.ChassisPosition);
    oldLinVel = KRBVectoVector(ShipState.ChassisLinVel);

    // See if state has changed enough, or enough time has passed, that we 
    // should send out another update by updating the state struct.
    if( !KIsAwake() )
    {
        return; // Never send updates if physics is at rest
    }

    if( VSize(oldPos - chassisPos) > 5 ||
        VSize(oldLinVel - chassisLinVel) > 1 ||
        Abs(ShipState.ServerThrottle - Throttle) > 0.1 ||
        Abs(ShipState.ServerSteering - Steering) > 0.1 ||
        Abs(ShipState.ServerRoll - Roll) > 0.1 ||
        bAfterburn != ShipState.ServerbAfterburn ||
        bBurn != ShipState.ServerbBurn ||
        Level.TimeSeconds > NextNetUpdateTime )
    {
        NextNetUpdateTime = Level.TimeSeconds + MaxNetUpdateInterval;
    }
    else
    {
        return;
    }

    ShipState.ChassisPosition = ChassisState.Position;
    ShipState.ChassisQuaternion = ChassisState.Quaternion;
    ShipState.ChassisLinVel = ChassisState.LinVel;
    ShipState.ChassisAngVel = ChassisState.AngVel;

    // Player Input
    ShipState.ServerSteering = Steering;
    ShipState.ServerThrottle = Throttle;
    ShipState.ServerRoll = Roll;

    // AfterBurner
    ShipState.ServerbAfterburn = bAfterburn;
    ShipState.ServerbBurn = bBurn;

    // This flag lets the client know this data is new.
    ShipState.bNewState = true;
    //Make sure ShipState gets replicated
    AVar++;
    if (AVar > 10)
        AVar=0;
}

simulated function Tick(float DeltaTime)
{
    Super.Tick(DeltaTime);
    if(!KIsAwake() && Controller!=None)
        KWake();
    if(Role == ROLE_Authority && Level.NetMode != NM_StandAlone)
        PackState();
    UpdateAcceleration(DeltaTime);
    UpdateExtraForce(DeltaTime);
}
simulated function UpdateAcceleration(float Delta)
{
    CurSteering = CurSteering + Steering * UnitAccRate * Delta;
    CurThrottle = CurThrottle + Throttle * UnitAccRate * Delta;
    CurRoll     = CurRoll     + Roll     * UnitAccRate * Delta;
    if(Steering==0)
        CurSteering=0;
    if(Throttle==0)
        CurThrottle=0;
    if(Roll==0)
        CurRoll=0;

    if(Abs(CurSteering)>Abs(Steering))
        CurSteering=Steering;
    if(Abs(CurThrottle)>Abs(Throttle))
        CurThrottle=Throttle;
    if(Abs(CurRoll)>Abs(Roll))
        CurRoll=Roll;

    if(bAfterBurn)
    {
        ReduceAfterBurnEnergy(); // just made this up, put it here incase you have something like this
        if(GetAfterburnEnergy()<=0) // Another fictional function...
        {
            bAfterBurn=False;
        }
        else
        {
            CThrust=AfterBurnThrust;
        }
    }
    if(bBurn && !bAfterBurn && CThrust!=1)
    {
        CThrust=1;
    }
    else if(!bBurn && !bAfterBurn && CThrust!=OldThrust)
    {
        CThrust=OldThrust;
    }

    if(TempThrust!=-1 && !bAfterBurn)
    {
        if(Abs(CurThrust-TempThrust)<0.01)
            CurThrust=TempThrust;
        if(CurThrust>TempThrust)
            CurThrust = CurThrust - UnitAccRate * Delta / 4; 
            // I made linear acceleration 4 times slower than rotation, you can do whatever you want though
        else if(CurThrust<TempThrust)
            CurThrust = CurThrust + UnitAccRate * Delta / 4;
    }
    else if(CurThrust!=CThrust && !bAfterBurn)
    {
        if(Abs(CurThrust-CThrust)<0.01)
            CurThrust=CThrust;
        else if(CurThrust>CThrust)
            CurThrust = CurThrust - UnitAccRate * Delta / 4;
        else if(CurThrust<CThrust)
            CurThrust = CurThrust + UnitAccRate * Delta / 4;
    }
    else if(CurThrust!=CThrust && bAfterBurn)
    {
        if(Abs(CurThrust-CThrust)<0.01)
            CurThrust=CThrust;
        else if(CurThrust>CThrust)
            CurThrust = CurThrust - UnitAccRate * Delta / 2.2; // Acceleration with afterburner a lot faster
        else if(CurThrust<CThrust)
            CurThrust = CurThrust + UnitAccRate * Delta / 2.2;
    }
}

simulated function UpdateExtraForce(float Delta)
{
    local vector worldForward, worldDown, worldLeft;

    worldForward = vect(1, 0, 0) >> Rotation;
    worldDown = vect(0, 0, -1) >> Rotation;
    worldLeft = vect(0, -1, 0) >> Rotation;

    ExtraForce = ExtraForce + worldForward * ForwardThrust * Delta * CurThrust; // Speed
    ExtraTorque = ExtraTorque + worldDown * TurnRate * Delta * CurSteering; // Yaw
    ExtraTorque = ExtraTorque + worldLeft * TurnRate * Delta * CurThrottle; // Pitch
    ExtraTorque = ExtraTorque + worldForward * TurnRate * Delta * -CurRoll; // Roll
}

simulated event KApplyForce(out vector Force, out vector Torque)
{
    // This actually does the applying of the piled up force
    Force = ExtraForce;
    Torque = ExtraTorque;
    ExtraForce = vect(0,0,0);
    ExtraTorque = vect(0,0,0);
}

DefaultProperties
{
     // Create Karma collision Params for ourselves, you can change whatever you want here
     Begin Object Class=KarmaParamsRBFull Name=KParams0
         KLinearDamping=2.000;
         KAngularDamping=2.000;
         KStartEnabled=True
         bHighDetailOnly=False
         bClientOnly=False
         bKDoubleTickRate=False
         KFriction=1.600000
         KActorGravScale = 0.0;
     KMass=2;
         Name="KParams0"
     End Object
     KParams=KarmaParamsRBFull'<MyPackage>.<MyShipClass>.KParams0'

     // And just some other variables:
     TurnRate=8
     ForwardThrust=5000
     UnitAccRate=2.0
     AfterBurnThrust=1.20 // basically means that afterburner goes at 120% of regular maximum speed
}

and that should be it, i hope i didnt miss anything...

Spark: KParams=KarmaParamsRBFull'<MyPackage>.<MyShipClass>.KParams0' <– Is this supposed to be a trap? ;) Took me a while to figure out that my ship didn't fly because this wasn't set to KParams0 and thus wasn't enabled at all. :)

Sir_Brizz: Zep, did you end up getting your Quaternion working for the indicator? I have a few ideas that work if you want to know what they are.

ProjectX: I'm a n00b to coding, but is it possible to take this code, and change it to create a "hovering vehicles" class, that basicly, wont go a certan height above ground, but, from high jumps, etc., go lower to the ground? I also saw that there was 3 types of thrust, is it possible to bind a key that will cycle through the flying types (for more precise flying, eg. for dog matches and realism)?

NickR: Does anyone have a working example of a flying vehicle?

Foxpaw: I do, but my mod is still quite a ways from release. The code above allegedly is working code for a flying vehicle, though I've never tested it.

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