Using Quaternions Efficiently in Real-time Applications

#ifndef _GAME_ENTITY_BASE_H
#define _GAME_ENTITY_BASE_H

#include "Math.h"

class GameEntityBase
{
public:
    virtual void updateAI() = 0;
    virtual void updatePursuitAction( const D3DXVECTOR3 &targetPos ) = 0;

    virtual void transformManyVertices( unsigned int numVerts ) = 0;

    virtual void calculateOrientation( float dt ) = 0;

    void UpdateRotation()
    {
        D3DXMATRIX m = quatToMatrix( ori_ );

        side_ = D3DXVECTOR3( m(0,0), m(1,0), m(2,0) );
        up_ = D3DXVECTOR3( m(0,1), m(1,1), m(2,1) );
        dir_ = D3DXVECTOR3( m(0,2), m(1,2), m(2,2) );
    }

protected:
    D3DXVECTOR3         dir_;
    D3DXVECTOR3         up_;
    D3DXVECTOR3         side_;

    float               yaw_;
    float               pitch_;
    float               roll_;

    D3DXVECTOR3         angularVel_;

    D3DXQUATERNION      ori_;
    D3DXVECTOR3         pos_;
};


#endif