CrystalSpace

Public API Reference

Main Page   Modules   Class Hierarchy   Alphabetical List   Compound List   File List   Compound Members   File Members  

quaterni.h

Go to the documentation of this file.
00001 /*
00002     Copyright (C) 2000 by Norman Kramer
00003 
00004     This library is free software; you can redistribute it and/or
00005     modify it under the terms of the GNU Library General Public
00006     License as published by the Free Software Foundation; either
00007     version 2 of the License, or (at your option) any later version.
00008 
00009     This library is distributed in the hope that it will be useful,
00010     but WITHOUT ANY WARRANTY; without even the implied warranty of
00011     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012     Library General Public License for more details.
00013 
00014     You should have received a copy of the GNU Library General Public
00015     License along with this library; if not, write to the Free
00016     Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
00017 */
00018 
00019 #ifndef __CS_QUATERNION_H__
00020 #define __CS_QUATERNION_H__
00021 
00028 #include "csgeom/math3d.h"
00029 #include "csgeom/matrix3.h"
00030 #include "qsqrt.h"
00031 
00035 class csQuaternion
00036 {
00037 public:
00039   inline void Init (float theR, float theX, float theY, float theZ)
00040   { r = theR; x = theX; y = theY; z = theZ; }
00041 
00043   csQuaternion () { Init(0, 0, 0, 0 ); }
00045   csQuaternion (float theR, float theX=0.0, float theY=0.0, float theZ=0.0)
00046   { Init (theR, theX, theY, theZ ); }
00048   csQuaternion (const csQuaternion& q) { Init (q.r, q.x, q.y, q.z); }
00050   csQuaternion (const csVector3& q) { Init (0, q.x, q.y, q.z); }
00051 
00053       csQuaternion (const csMatrix3& smat);
00054 
00056   inline friend csQuaternion operator+ (const csQuaternion& q1, const csQuaternion& q2)
00057   { return csQuaternion (q1.r + q2.r, q1.x + q2.x, q1.y + q2.y, q1.z + q2.z ); }
00059   inline friend csQuaternion operator- (const csQuaternion& q1, const csQuaternion& q2)
00060   { return csQuaternion (q1.r - q2.r, q1.x - q2.x, q1.y - q2.y, q1.z - q2.z ); }
00062   inline friend csQuaternion operator* (const csQuaternion& q1, const csQuaternion& q2)
00063   { return csQuaternion (q1.r*q2.r -  q1.x*q2.x - q1.y*q2.y - q1.z*q2.z,
00064              q1.y*q2.z -  q1.z*q2.y + q1.r*q2.x + q1.x*q2.r,
00065              q1.z*q2.x -  q1.x*q2.z + q1.r*q2.y + q1.y*q2.r,
00066              q1.x*q2.y -  q1.y*q2.x + q1.r*q2.z + q1.z*q2.r); }
00067 
00069   csQuaternion& operator*= (const csQuaternion& q2)
00070   {
00071     Init (r*q2.r -  x*q2.x - y*q2.y - z*q2.z,
00072       y*q2.z -  z*q2.y + r*q2.x + x*q2.r,
00073       z*q2.x -  x*q2.z + r*q2.y + y*q2.r,
00074       x*q2.y -  y*q2.x + r*q2.z + z*q2.r);
00075     return *this;
00076   }
00077 
00079   void Conjugate () { Init (r, -x, -y, -z); }
00080 
00082     void Negate () { Init(-r, -x, -y, -z); }
00083 
00085     void Invert();
00086 
00091     void GetAxisAngle(csVector3& axis, float& phi) const;
00092 
00097     void SetWithAxisAngle(csVector3 axis, float phi);
00098 
00104   void PrepRotation (float angle, csVector3 vec)
00105   {
00106     double theSin = sin (angle / 2.0f);
00107     Init ((float) cos (angle / 2.0f), vec.x * theSin, vec.y * theSin, vec.z * theSin);
00108   }
00109 
00111   csVector3 Rotate (csVector3 vec)
00112   {
00113     csQuaternion p (vec);
00114     csQuaternion qConj (r, -x, -y, -z);
00115 
00116     p = *this * p;
00117     p *= qConj;
00118     return csVector3 (p.x, p.y, p.z);
00119   }
00120 
00122   void Normalize ()
00123   {
00124     float     dist, square;
00125 
00126     square = x * x + y * y + z * z + r * r;
00127 
00128     if (square > 0.0)
00129         dist = (float)(1.0 / sqrt(square));
00130     else dist = 1;
00131 
00132     x *= dist;
00133     y *= dist;
00134     z *= dist;
00135     r *= dist;
00136 
00137     /*if(x*x + y*y + z*z > .999)
00138     {
00139       // Severe problems...
00140       float inverselen = 1.0f / (x*x + y*y + z*z);
00141       x *= inverselen;
00142       y *= inverselen;
00143       z *= inverselen;
00144       if(r > 0) r = -1 + r;
00145       else r = 1 + r;
00146     }
00147     else
00148     {
00149       r = qsqrt(1.0f - x*x - y*y - z*z);
00150       }*/
00151   }
00152 
00158   void SetWithEuler(const csVector3 &rot);
00159 
00163   csQuaternion ToAxisAngle() const;
00164 
00170   csQuaternion Slerp (const csQuaternion &quat2, float slerp) const;
00171 
00172 //csQuaternion Lerp(const csQuaternion& quat2, float ratio) const;
00173 
00174   float r,x,y,z;
00175 };
00176 
00179 #endif // __CS_QUATERNION_H__

Generated for Crystal Space by doxygen 1.2.14