WFMath 0.3.11

quaternion.h

00001 // quaternion.h (based on the Quaternion class from eris)
00002 //
00003 //  The WorldForge Project
00004 //  Copyright (C) 2002  The WorldForge Project
00005 //
00006 //  This program is free software; you can redistribute it and/or modify
00007 //  it under the terms of the GNU General Public License as published by
00008 //  the Free Software Foundation; either version 2 of the License, or
00009 //  (at your option) any later version.
00010 //
00011 //  This program is distributed in the hope that it will be useful,
00012 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 //  GNU General Public License for more details.
00015 //
00016 //  You should have received a copy of the GNU General Public License
00017 //  along with this program; if not, write to the Free Software
00018 //  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
00019 //
00020 //  For information about WorldForge and its authors, please contact
00021 //  the Worldforge Web Site at http://www.worldforge.org.
00022 //
00023 
00024 // Author: Ron Steinke
00025 
00026 #ifndef WFMATH_QUATERNION_H
00027 #define WFMATH_QUATERNION_H
00028 
00029 #include <wfmath/vector.h>
00030 #include <wfmath/rotmatrix.h>
00031 
00032 namespace WFMath {
00033 
00035 
00039 class Quaternion
00040 {
00041  public:
00043   Quaternion () : m_valid(false) {}
00045 
00048   Quaternion (CoordType w_in, CoordType x_in, CoordType y_in, CoordType z_in);
00050   Quaternion (int axis, CoordType angle) {rotation(axis, angle);}
00052   Quaternion (const Vector<3>& axis, CoordType angle) {rotation(axis, angle);}
00054 
00057   explicit Quaternion (const Vector<3>& axis) {rotation(axis);} // angle == axis.mag()
00059   Quaternion (const Quaternion& p) : m_w(p.m_w), m_vec(p.m_vec),
00060                                      m_valid(p.m_valid), m_age(p.m_age) {}
00062   explicit Quaternion (const AtlasInType& a) {fromAtlas(a);}
00063 
00064   ~Quaternion() {}
00065 
00066   friend std::ostream& operator<<(std::ostream& os, const Quaternion& p);
00067   friend std::istream& operator>>(std::istream& is, Quaternion& p);
00068 
00070   AtlasOutType toAtlas() const;
00072   void fromAtlas(const AtlasInType& a);
00073 
00074   Quaternion& operator= (const Quaternion& rhs)
00075         {m_w = rhs.m_w; m_vec = rhs.m_vec; m_valid = rhs.m_valid; m_age = rhs.m_age; return *this;}
00076 
00077   // This regards q and -1*q as equal, since they give the
00078   // same RotMatrix<3>
00079   bool isEqualTo(const Quaternion &q, double epsilon = WFMATH_EPSILON) const;
00080 
00081   bool operator== (const Quaternion& rhs) const {return isEqualTo(rhs);}
00082   bool operator!= (const Quaternion& rhs) const {return !isEqualTo(rhs);}
00083 
00084   bool isValid() const {return m_valid;}
00085 
00087   Quaternion& identity() {m_w = 1; m_vec.zero(); m_valid = true; m_age = 0; return *this;} // Set to null rotation
00088 
00089   // Operators
00090 
00092   Quaternion& operator*= (const Quaternion& rhs);
00094   Quaternion& operator/= (const Quaternion& rhs);
00096   Quaternion operator* (const Quaternion& rhs) const {
00097     Quaternion out(*this);
00098     out *= rhs;
00099     return out;
00100   }
00102   Quaternion operator/ (const Quaternion& rhs) const {
00103     Quaternion out(*this);
00104     out /= rhs;
00105     return out;
00106   }
00107 
00108   // Functions
00109 
00110   // Returns "not_flip", similar to RotMatrix<>.toEuler()
00112 
00121   bool fromRotMatrix(const RotMatrix<3>& m);
00122 
00124   Quaternion inverse() const;
00125 
00127   Quaternion& rotate(const RotMatrix<3>&);
00128 
00130   Quaternion& rotate(const Quaternion& q) {return operator*=(q);}
00131 
00133   Quaternion& rotation(int axis, CoordType angle);
00135   Quaternion& rotation(const Vector<3>& axis, CoordType angle);
00137 
00140   Quaternion& rotation(const Vector<3>& axis); // angle == axis.mag()
00141 
00143   Quaternion& rotation(const Vector<3>& from, const Vector<3>& to);
00144 
00145   // documented elsewhere
00146   template<const int dim>
00147   friend Vector<dim>& Vector<dim>::rotate(const Quaternion& q);
00148   template<const int dim>
00149   friend RotMatrix<dim>& RotMatrix<dim>::fromQuaternion(const Quaternion& q,
00150                                                         const bool not_flip);
00151 
00153   CoordType scalar() const              {return m_w;}
00155   const Vector<3>& vector() const       {return m_vec;}
00156 
00158   void normalize();
00160   unsigned age() const {return m_age;}
00161 
00162  private:
00163   Quaternion(bool valid) : m_valid(valid), m_age(1) {}
00164   void checkNormalization() {if(m_age >= WFMATH_MAX_NORM_AGE && m_valid) normalize();}
00165   CoordType m_w;
00166   Vector<3> m_vec;
00167   bool m_valid;
00168   unsigned m_age;
00169 };
00170 
00171 } // namespace WFMath
00172 
00173 #endif  // WFMATH_QUATERNION_H