CzBox2dJoint.h

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// 
//
// AppEasy SDK - Cross Platform Multi-purpose Game and App Engine
//
// Developed by Matthew Hopwood of Pocketeers Limited - www.pocketeers.co.uk
//
// For updates, tutorials and more details check out www.appeasymobile.com
//
// This code is provided free of charge and without any warranty whatsoever. You must ensure that this whole notice is present in all files and derivatives, so the reader knows its origin.
// If you use this SDK in your product then please ensure that you credit AppEasy's usage appropriately. Please see www.appeasymobile.com for licensing details and support
//
//

#if !defined(_CZ_BOX2D_JOINT_H_)
#define _CZ_BOX2D_JOINT_H_

#include "CzUtil.h"
#include "CzString.h"
#include "CzXoml.h"
#include "CzShapes.h"

#include "Box2D/Box2D.h"

class CzBox2dWorld;
class CzBox2dBody;

//
//
//
//
// CzBox2dJoint - Box2D physics joint
//
//
//
//
enum eCzBox2dJointType
{
    JT_Weld, 
    JT_Distance, 
    JT_Revolute, 
    JT_Prismatic, 
    JT_Pulley, 
    JT_Wheel, 
};

struct IzBox2dJoint
{
    eCzBox2dJointType   Type;                   ///< Type of joint
#if defined (_DEBUG)
    CzString            Name;                   ///< Joint name
#endif  // _DEBUG
    unsigned int        NameHash;               ///< Joint name hash
    CzBox2dBody*        BodyA;                  ///< Body A
    CzBox2dBody*        BodyB;                  ///< Body B
    b2Vec2              AnchorA;                ///< Body A world anchor pos
    b2Vec2              AnchorB;                ///< Body B world anchor pos
    bool                SelfCollide;            ///< True to allow self collision

    virtual void        Create(CzBox2dWorld* world) = 0;
    virtual b2Joint*    getJoint() = 0;
    void                setName(const char* name)
    {
#if defined (_DEBUG)
        Name = name;
#endif  // _DEBUG
        NameHash = CzString::CalculateHash(name);
    }
};

struct CzBox2dJointWeld : public IzBox2dJoint
{
    float               ReferenceAngle;     // Reference angle
    b2WeldJoint*        Joint;

    CzBox2dJointWeld() { Type = JT_Distance; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

struct CzBox2dJointDistance : public IzBox2dJoint
{
    float               Length;             // Max length between bosy A and B
    float               Frequency;          // Harmonic oscilation Frequency in Hz
    float               Damping;            // Oscillation damping (1.0 for no oscillation)
    b2DistanceJoint*    Joint;

    CzBox2dJointDistance() : Length(-1), Frequency(-1), Damping(-1) { Type = JT_Distance; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

struct CzBox2dJointRevolute : public IzBox2dJoint
{
    bool                LimitJoint;         // Imited joint rotation
    bool                MotorEnabled;       // Enable motor
    float               LowerAngle;         // Lower rotation limit
    float               UpperAngle;         // Upper rotation limit
    float               MotorSpeed;         // Motor speed
    float               MaxMotorTorque;     // Max motor torque
    float               ReferenceAngle;     // Reference angle
    b2RevoluteJoint*    Joint;

    CzBox2dJointRevolute() : LimitJoint(false), MotorEnabled(false), ReferenceAngle(0) { Type = JT_Revolute; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

struct CzBox2dJointPrismatic : public IzBox2dJoint
{
    b2Vec2              Axis;               // Axis of movement
    bool                LimitJoint;         // Limit joint translation
    bool                MotorEnabled;       // Emable motor
    float               LowerTranslation;   // Lower translation limit
    float               UpperTranslation;   // Upper translation limit
    float               MotorSpeed;         // Motor speed
    float               MaxMotorForce;      // Max motor force
    float               ReferenceAngle;     // Reference angle
    b2PrismaticJoint*   Joint;

    CzBox2dJointPrismatic() : LimitJoint(false), MotorEnabled(false), ReferenceAngle(0) { Type = JT_Prismatic; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

struct CzBox2dJointPulley : public IzBox2dJoint
{
    b2Vec2              GroundAnchorA;  // Body A world ground anchor pos
    b2Vec2              GroundAnchorB;  // Body B world ground anchor pos
    float               LengthA;        // Distance between Body A and Ground Anchor A
    float               LengthB;        // Distance between Body B and Ground Anchor B
    float               Ratio;          // Ratio between rate of change of both sides
    b2PulleyJoint*      Joint;

    CzBox2dJointPulley() : Ratio(1.0f), LengthA(0), LengthB(0) { Type = JT_Pulley; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

struct CzBox2dJointWheel : public IzBox2dJoint
{
    b2Vec2              Axis;           // Axis
    bool                MotorEnabled;   // Motor enabled
    float               MotorSpeed;     // Motor speed
    float               MaxMotorTorque; // Max motor torque
    float               Frequency;      // Harmonic oscilation Frequency in Hz
    float               Damping;        // Oscillation damping (1.0 for no oscillation)
    b2WheelJoint*       Joint;

    CzBox2dJointWheel() : MotorEnabled(false) { Type = JT_Wheel; }

    // Initialise the joint
    void                Create(CzBox2dWorld* world);
    b2Joint*            getJoint()      { return Joint; }
};

//
//
//
//
// CzBox2dJoints - Box2D physics joints XOML command
//
//
//
//
class CzBox2dJoints : public IzXomlResource
{
public:
    CzBox2dJoints() { setClassType("joints"); }

    // Implementation of IzXomlResource interface
    int                 LoadFromXoml(IzXomlResource* parent, bool load_children, CzXmlNode* node);
};

//
//  CzBox2dJointsCreator - Creates an instance of Box2DJoints object
//
class CzBox2dJointsCreator : public IzXomlClassCreator
{
public:
    CzBox2dJointsCreator()
    {
        setClassName("joints");
    }
    IzXomlResource* CreateInstance(IzXomlResource* parent)  { return new CzBox2dJoints(); }
};



#endif // _CZ_BOX2D_JOINT_H_