vcglib/vcg/math/quaternion.h

293 lines
8.4 KiB
C++

/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004 \/)\/ *
* Visual Computing Lab /\/| *
* ISTI - Italian National Research Council | *
* \ *
* All rights reserved. *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License (http://www.gnu.org/licenses/gpl.txt) *
* for more details. *
* *
****************************************************************************/
/****************************************************************************
History
$Log: not supported by cvs2svn $
Revision 1.8 2004/10/07 13:54:03 ganovelli
added SetIdentity
Revision 1.7 2004/04/07 10:48:37 cignoni
updated access to matrix44 elements through V() instead simple []
Revision 1.6 2004/03/25 14:57:49 ponchio
Microerror. ($LOG$ -> $Log: not supported by cvs2svn $
Microerror. ($LOG$ -> Revision 1.8 2004/10/07 13:54:03 ganovelli
Microerror. ($LOG$ -> added SetIdentity
Microerror. ($LOG$ ->
Microerror. ($LOG$ -> Revision 1.7 2004/04/07 10:48:37 cignoni
Microerror. ($LOG$ -> updated access to matrix44 elements through V() instead simple []
Microerror. ($LOG$ ->
****************************************************************************/
#ifndef QUATERNION_H
#define QUATERNION_H
#include <vcg/space/point3.h>
#include <vcg/space/point4.h>
#include <vcg/math/base.h>
#include <vcg/math/matrix44.h>
namespace vcg {
/** Classe quaternion.
A quaternion is a point in the unit sphere in four dimension: all
rotations in three-dimensional space can be represented by a quaternion.
*/
template<class S> class Quaternion: public Point4<S> {
public:
Quaternion() {}
Quaternion(const S v0, const S v1, const S v2, const S v3): Point4<S>(v0,v1,v2,v3){}
Quaternion(const Point4<S> p) : Point4<S>(p) {}
Quaternion(const S phi, const Point3<S> &a);
Quaternion operator*(const S &s) const;
//Quaternion &operator*=(S d);
Quaternion operator*(const Quaternion &q) const;
Quaternion &operator*=(const Quaternion &q);
void Invert();
void SetIdentity();
void FromAxis(const S phi, const Point3<S> &a);
void ToAxis(S &phi, Point3<S> &a ) const;
void FromMatrix(Matrix44<S> &m);
void ToMatrix(Matrix44<S> &m) const;
Point3<S> Rotate(const Point3<S> vec) const;
};
template <class S> Quaternion<S> Interpolate(const Quaternion<S> a, const Quaternion<S> b, double t);
template <class S> Quaternion<S> &Invert(Quaternion<S> &q);
template <class S> Quaternion<S> Inverse(const Quaternion<S> &q);
//Implementation
template <class S>
void Quaternion<S>::SetIdentity(){
FromAxis(0, Point3<S>(1, 0, 0));
}
template <class S> Quaternion<S>::Quaternion(const S phi, const Point3<S> &a) {
FromAxis(phi, a);
}
template <class S> Quaternion<S> Quaternion<S>::operator*(const S &s) const {
return (Quaternion(V(0)*s,V(1)*s,V(2)*s,V(3)*s));
}
template <class S> Quaternion<S> Quaternion<S>::operator*(const Quaternion &q) const {
Point3<S> t1(V(1), V(2), V(3));
Point3<S> t2(q.V(1), q.V(2), q.V(3));
S d = t2 * t1;
Point3<S> t3 = t1 ^ t2;
t1 *= q.V(0);
t2 *= V(0);
Point3<S> tf = t1 + t2 +t3;
Quaternion<S> t;
t.V(0) = V(0) * q.V(0) - d;
t.V(1) = tf[0];
t.V(2) = tf[1];
t.V(3) = tf[2];
return t;
}
template <class S> Quaternion<S> &Quaternion<S>::operator*=(const Quaternion &q) {
S ww = V(0) * q.V(0) - V(1) * q.V(1) - V(2) * q.V(2) - V(3) * q.V(3);
S xx = V(0) * q.V(1) + V(1) * q.V(0) + V(2) * q.V(3) - V(3) * q.V(2);
S yy = V(0) * q.V(2) - V(1) * q.V(3) + V(2) * q.V(0) + V(3) * q.V(1);
V(0) = ww;
V(1) = xx;
V(2) = yy;
V(3) = V(0) * q.V(3) + V(1) * q.V(2) - V(2) * q.V(1) + V(3) * q.V(0);
return *this;
}
template <class S> void Quaternion<S>::Invert() {
V(1)*=-1;
V(2)*=-1;
V(3)*=-1;
}
template <class S> void Quaternion<S>::FromAxis(const S phi, const Point3<S> &a) {
Point3<S> b = a;
b.Normalize();
S s = math::Sin(phi/(S(2.0)));
V(0) = math::Cos(phi/(S(2.0)));
V(1) = b[0]*s;
V(2) = b[1]*s;
V(3) = b[2]*s;
}
template <class S> void Quaternion<S>::ToAxis(S &phi, Point3<S> &a) const {
S s = math::Asin(V(0))*S(2.0);
phi = math::Acos(V(0))*S(2.0);
if(s < 0)
phi = - phi;
a.V(0) = V(1);
a.V(1) = V(2);
a.V(2) = V(3);
a.Normalize();
}
template <class S> Point3<S> Quaternion<S>::Rotate(const Point3<S> p) const {
Quaternion<S> co = *this;
co.Invert();
Quaternion<S> tmp(0, p.V(0), p.V(1), p.V(2));
tmp = (*this) * tmp * co;
return Point3<S>(tmp.V(1), tmp.V(2), tmp.V(3));
}
template <class S> void Quaternion<S>::ToMatrix(Matrix44<S> &m) const {
S q00 = V(1)*V(1);
S q01 = V(1)*V(2);
S q02 = V(1)*V(3);
S q03 = V(1)*V(0);
S q11 = V(2)*V(2);
S q12 = V(2)*V(3);
S q13 = V(2)*V(0);
S q22 = V(3)*V(3);
S q23 = V(3)*V(0);
m[0][0] = (S)(1.0-(q11 + q22)*2.0);
m[1][0] = (S)((q01 - q23)*2.0);
m[2][0] = (S)((q02 + q13)*2.0);
m[3][0] = (S)0.0;
m[0][1] = (S)((q01 + q23)*2.0);
m[1][1] = (S)(1.0-(q22 + q00)*2.0);
m[2][1] = (S)((q12 - q03)*2.0);
m[3][1] = (S)0.0;
m[0][2] = (S)((q02 - q13)*2.0);
m[1][2] = (S)((q12 + q03)*2.0);
m[2][2] = (S)(1.0-(q11 + q00)*2.0);
m[3][2] = (S)0.0;
m[0][3] = (S)0.0;
m[1][3] = (S)0.0;
m[2][3] = (S)0.0;
m[3][3] = (S)1.0;
}
///warning m deve essere una matrice di rotazione pena il disastro.
template <class S> void Quaternion<S>::FromMatrix(Matrix44<S> &m) {
S Sc;
S t = (m.V()[0] + m.V()[5] + m.V()[10] + (S)1.0);
if(t > 0) {
Sc = (S)0.5 / math::Sqrt(t);
V(0) = (S)0.25 / Sc;
V(1) = ( m.V()[9] - m.V()[6] ) * Sc;
V(2) = ( m.V()[2] - m.V()[8] ) * Sc;
V(3) = ( m.V()[4] - m.V()[1] ) * Sc;
} else {
if(m.V()[0] > m.V()[5] && m.V()[0] > m.V()[10]) {
Sc = math::Sqrt( (S)1.0 + m.V()[0] - m.V()[5] - m.V()[10] ) * (S)2.0;
V(1) = (S)0.5 / Sc;
V(2) = (m.V()[1] + m.V()[4] ) / Sc;
V(3) = (m.V()[2] + m.V()[8] ) / Sc;
V(0) = (m.V()[6] + m.V()[9] ) / Sc;
} else if( m.V()[5] > m.V()[10]) {
Sc = math::Sqrt( (S)1.0 + m.V()[5] - m.V()[0] - m.V()[10] ) * (S)2.0;
V(1) = (m.V()[1] + m.V()[4] ) / Sc;
V(2) = (S)0.5 / Sc;
V(3) = (m.V()[6] + m.V()[9] ) / Sc;
V(0) = (m.V()[2] + m.V()[8] ) / Sc;
} else {
Sc = math::Sqrt( (S)1.0 + m.V()[10] - m.V()[0] - m.V()[5] ) * (S)2.0;
V(1) = (m.V()[2] + m.V()[8] ) / Sc;
V(2) = (m.V()[6] + m.V()[9] ) / Sc;
V(3) = (S)0.5 / Sc;
V(0) = (m.V()[1] + m.V()[4] ) / Sc;
}
}
}
template <class S> Quaternion<S> &Invert(Quaternion<S> &m) {
m.Invert();
return m;
}
template <class S> Quaternion<S> Inverse(const Quaternion<S> &m) {
Quaternion<S> a = m;
a.Invert();
return a;
}
template <class S> Quaternion<S> Interpolate(const Quaternion<S> a, const Quaternion<S> b, double t) {
double v = a.V(0) * b.V(0) + a.V(1) * b.V(1) + a.V(2) * b.V(2) + a.V(3) * b.V(3);
double phi = Acos(v);
if(phi > 0.01) {
a = a * (Sin(phi *(1-t))/Sin(phi));
b = b * (Sin(phi * t)/Sin(phi));
}
Quaternion<S> c;
c.V(0) = a.V(0) + b.V(0);
c.V(1) = a.V(1) + b.V(1);
c.V(2) = a.V(2) + b.V(2);
c.V(3) = a.V(3) + b.V(3);
if(v < -0.999) { //almost opposite
double d = t * (1 - t);
if(c.V(0) == 0)
c.V(0) += d;
else
c.V(1) += d;
}
c.Normalize();
return c;
}
typedef Quaternion<float> Quaternionf;
typedef Quaternion<double> Quaterniond;
} // end namespace
#endif