mitkVis2Quaternion.h

/*=========================================================================

  Program:   3DMed
  Date:      $Date: 2014-02-25 18:30:00 +0800 $
  Version:   $Version: 4.6.0 $
  Copyright: MIPG, Institute of Automation, Chinese Academy of Sciences

=========================================================================*/

#ifndef _Quaternion_h
#define _Quaternion_h

#include "mitkVis2Matrix4x4.h"

class MITK_VISUALIZATION2_API mitkVis2Quaternion
{
public:

    mitkVis2Quaternion();   
    mitkVis2Quaternion(float ax, float ay, float az, float angle);  
    mitkVis2Quaternion& operator=(const mitkVis2Quaternion &q)  
    {
        x = q.x;
        y = q.y;
        z = q.z;
        w = q.w;
        return(*this);  
    }
    mitkVis2Quaternion(const mitkVis2Quaternion &q)                    
    {
        x = q.x;
        y = q.y;
        z = q.z;
        w = q.w;
    }
    
    void Identity()
    {
        x   = 0.0f;
        y   = 0.0f;
        z   = 0.0f;
        w   = 1.0f;
    }
    void Normalize()
    {
            float normInv = 1.0f/sqrtf(x*x+y*y+z*z+w*w);
            x *= normInv;
            y *= normInv;
            z *= normInv;
            w *= normInv;   
            return;
    }
    
    mitkVis2Quaternion& operator *= (const mitkVis2Quaternion&);    
    mitkVis2Matrix4x4 ToMatrix () const
    {
        mitkVis2Matrix4x4 mat;
        float *m = mat;
        m[0]  = 1.0f - 2.0f * (y*y + z*z);
        m[1]  = 2.0f * (x*y + z*w);
        m[2]  = 2.0f * (z*x - y*w);
        m[3]  = 0.0f;
    
        m[4]  = 2.0f * (x*y - z*w);
        m[5]  = 1.0f - 2.0f * (z*z + x*x);
        m[6]  = 2.0f * (y*z + x*w);
        m[7]  = 0.0f;
    
        m[8]  = 2.0f * (z*x + y*w);
        m[9]  = 2.0f * (y*z - x*w);
        m[10] = 1.0f - 2.0f * (x*x + y*y);
        m[11] = 0.0f;
    
        m[12] = 0.0f;
        m[13] = 0.0f;
        m[14] = 0.0f;
        m[15] = 1.0f;   
        return mat;
    }
    
    float   x,y,z,w;            

};

inline mitkVis2Quaternion operator * (const mitkVis2Quaternion &p, const mitkVis2Quaternion &q)
{
    mitkVis2Quaternion res;

    res.w   = p.w*q.w - p.x*q.x - p.y*q.y - p.z*q.z;
    res.x   = p.w*q.x + p.x*q.w + p.y*q.z - p.z*q.y;
    res.y   = p.w*q.y + p.y*q.w + p.z*q.x - p.x*q.z;
    res.z   = p.w*q.z + p.z*q.w + p.x*q.y - p.y*q.x;

    return res;
}
inline mitkVis2Quaternion& mitkVis2Quaternion::operator *= (const mitkVis2Quaternion& q)
{
    *this=*this*q;
    return (*this); 
}
        

#endif

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