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lib-game-delta3d-demos-TankTarget-TankActor.h / h



  /* -*-c++-*-
   * TutorialLibrary - TankActor (.h & .cpp) - Using 'The MIT License'
   * Copyright (C) 2006-2008, Alion Science and Technology Corporation
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
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   *
author: Curtiss Murphy */
ifndef __GM_TUTORIAL_TANK_ACTOR__ define __GM_TUTORIAL_TANK_ACTOR__ include <export.h> include <dtCore/refptr.h> include <dtActors/gamemeshactor.h> include <dtCore/particlesystem.h> include <dtCore/isector.h> include <dtCore/transform.h> include <osgSim/DOFTransform>
This class is the actor that represents a hover tank of sorts. It knows how to respond to keyboard presses (I, J, K, L to steer). It also listens for "ToggleEngine" & "SpeedBoost" GameEvents. This actor correctly handles TickLocal versus TickRemote.

  
  class TUTORIAL_TANK_EXPORT TankActor : public dtActors::GameMeshActor
  {
     public:
  
        // Constant identifier for our game event handler method.
        static const std::string EVENT_HANDLER_NAME;
  
        // Constructs the tank actor.
        TankActor(dtGame::GameActorProxy& proxy);
  
        
This method is an invokable for when a local object receives a tick.
parameter: tickMessage A message containing tick related information.

  
        virtual void OnTickLocal(const dtGame::TickMessage& tickMessage);
  
        
This method is an invokable for when a remote object receives a tick.
parameter: tickMessage A message containing tick related information.

  
        virtual void OnTickRemote(const dtGame::TickMessage& tickMessage);
  
        
Generic handler (Invokable) for messages. Overridden from base class. This is the default invokable on GameActorProxy.

  
        virtual void ProcessMessage(const dtGame::Message& message);
  
        
Sets the velocity of our tank actor.
parameter: velocity The new velocity. @note This may cause an actor update message

  
        void SetVelocity(float velocity);
  
        //
returns: The actor's current velocity. float GetVelocity() const { return mVelocity; }
Sets the turn rate of our tank actor.
parameter: rate The new turn rate in degrees per second. @note This may cause an actor update message

  
        void SetTurnRate(float rate);
  
        //
returns: The actor's current turn rate. float GetTurnRate() const { return mTurnRate; }
This is a method called by the game event invokable when a game event message is passed through the game manager.
parameter: msg The message containing the game event.

  
        void HandleGameEvent(const dtGame::Message& msg);
  
        // Called when the actor has been added to the game manager.
        // You can respond to OnEnteredWorld on either the proxy or actor or both.
        virtual void OnEnteredWorld();
  
     protected:
        virtual ~TankActor() { } ;
  
     private:
        // do our internal velocity/turn calculations based on keyboard status
        // only relevant for Local mode (ie, not when remote)
        void ComputeVelocityAndTurn(float deltaSimTime);
  
        // calculate new position based on turn rate and velocity
        // relevant in both local and remote
        void MoveTheTank(float deltaSimTime);
  
        void CheckForNewTarget();
  
        // Utility method to fire a target changed message using mCurrentTargetId
        void FireTargetChangedMessage();
  
        // private vars
        dtCore::RefPtr<dtCore::ParticleSystem> mDust;
        dtCore::RefPtr<dtCore::ParticleSystem> mCannonShot;
  
        float mVelocity;
        float mAddOnVelocity;
        float mTurnRate;
        bool  mIsEngineRunning;
        float mLastReportedVelocity;
        dtCore::RefPtr<dtCore::Isector> mIsector;
        dtCore::UniqueId mNoTargetId;
        dtCore::UniqueId mCurrentTargetId;
        dtCore::Transform mOriginalPosition;
  
        bool mPropertiesUpdated;
  
        dtCore::RefPtr<osgSim::DOFTransform> mDOFTran;
  
  };
  
  
Our proxy class for the hover tank actor. The proxy contains properties, invokables, and hover tank actor.

  
  class TUTORIAL_TANK_EXPORT TankActorProxy : public dtActors::GameMeshActorProxy
  {
     public:
        // Constructs the proxy.
        TankActorProxy();
  
        // Creates the properties that are custom to the hover tank proxy.
        virtual void BuildPropertyMap();
  
     protected:
        virtual ~TankActorProxy() { };
  
        // Creates an instance of our hover tank actor
        virtual void CreateActor();
  
        // Called when this proxy is added to the game manager (ie, the "world")
        // You can respond to OnEnteredWorld on either the proxy or actor or both.
        virtual void OnEnteredWorld();
  };
  
  endif
  


(C) Æliens 04/09/2009

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