--- /dev/null
+///////////////////////////////////////////////////////////////////////////
+//
+// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
+// Digital Ltd. LLC
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Industrial Light & Magic nor the names of
+// its contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+///////////////////////////////////////////////////////////////////////////
+
+
+
+#ifndef INCLUDED_IMATHQUAT_H
+#define INCLUDED_IMATHQUAT_H
+
+//----------------------------------------------------------------------
+//
+// template class Quat<T>
+//
+// "Quaternions came from Hamilton ... and have been an unmixed
+// evil to those who have touched them in any way. Vector is a
+// useless survival ... and has never been of the slightest use
+// to any creature."
+//
+// - Lord Kelvin
+//
+// This class implements the quaternion numerical type -- you
+// will probably want to use this class to represent orientations
+// in R3 and to convert between various euler angle reps. You
+// should probably use Imath::Euler<> for that.
+//
+//----------------------------------------------------------------------
+
+#include "ImathExc.h"
+#include "ImathMatrix.h"
+
+#include <iostream>
+
+namespace Imath {
+
+#if (defined _WIN32 || defined _WIN64) && defined _MSC_VER
+// Disable MS VC++ warnings about conversion from double to float
+#pragma warning(disable:4244)
+#endif
+
+template <class T>
+class Quat;
+
+template<class T>
+Quat<T> slerp (const Quat<T> &q1,const Quat<T> &q2, T t);
+
+template<class T>
+Quat<T> squad (const Quat<T> &q1,const Quat<T> &q2,
+ const Quat<T> &qa,const Quat<T> &qb, T t);
+
+template<class T>
+void intermediate (const Quat<T> &q0, const Quat<T> &q1,
+ const Quat<T> &q2, const Quat<T> &q3,
+ Quat<T> &qa, Quat<T> &qb);
+
+template <class T>
+class Quat
+{
+ public:
+
+ T r; // real part
+ Vec3<T> v; // imaginary vector
+
+ //-----------------------------------------------------
+ // Constructors - default constructor is identity quat
+ //-----------------------------------------------------
+
+ Quat() : r(1), v(0,0,0) {}
+
+ template <class S>
+ Quat( const Quat<S>& q) : r(q.r), v(q.v) {}
+
+ Quat( T s, T i, T j, T k ) : r(s), v(i,j,k) {}
+
+ Quat( T s, Vec3<T> d ) : r(s), v(d) {}
+
+ static Quat<T> identity() { return Quat<T>(); }
+
+ //------------------------------------------------
+ // Basic Algebra - Operators and Methods
+ // The operator return values are *NOT* normalized
+ //
+ // operator^ is 4D dot product
+ // operator/ uses the inverse() quaternion
+ // operator~ is conjugate -- if (S+V) is quat then
+ // the conjugate (S+V)* == (S-V)
+ //
+ // some operators (*,/,*=,/=) treat the quat as
+ // a 4D vector when one of the operands is scalar
+ //------------------------------------------------
+
+ const Quat<T>& operator= (const Quat<T>&);
+ const Quat<T>& operator*= (const Quat<T>&);
+ const Quat<T>& operator*= (T);
+ const Quat<T>& operator/= (const Quat<T>&);
+ const Quat<T>& operator/= (T);
+ const Quat<T>& operator+= (const Quat<T>&);
+ const Quat<T>& operator-= (const Quat<T>&);
+ T& operator[] (int index); // as 4D vector
+ T operator[] (int index) const;
+
+ template <class S> bool operator == (const Quat<S> &q) const;
+ template <class S> bool operator != (const Quat<S> &q) const;
+
+ Quat<T>& invert(); // this -> 1 / this
+ Quat<T> inverse() const;
+ Quat<T>& normalize(); // returns this
+ Quat<T> normalized() const;
+ T length() const; // in R4
+
+ //-----------------------
+ // Rotation conversion
+ //-----------------------
+
+ Quat<T>& setAxisAngle(const Vec3<T>& axis, T radians);
+ Quat<T>& setRotation(const Vec3<T>& fromDirection,
+ const Vec3<T>& toDirection);
+
+ T angle() const;
+ Vec3<T> axis() const;
+
+ Matrix33<T> toMatrix33() const;
+ Matrix44<T> toMatrix44() const;
+
+ Quat<T> log() const;
+ Quat<T> exp() const;
+};
+
+
+//--------------------
+// Convenient typedefs
+//--------------------
+
+typedef Quat<float> Quatf;
+typedef Quat<double> Quatd;
+
+
+//---------------
+// Implementation
+//---------------
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator= (const Quat<T>& q)
+{
+ r = q.r;
+ v = q.v;
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator*= (const Quat<T>& q)
+{
+ T rtmp = r * q.r - (v ^ q.v);
+ v = r * q.v + v * q.r + v % q.v;
+ r = rtmp;
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator*= (T t)
+{
+ r *= t;
+ v *= t;
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator/= (const Quat<T>& q)
+{
+ *this = *this * q.inverse();
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator/= (T t)
+{
+ r /= t;
+ v /= t;
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator+= (const Quat<T>& q)
+{
+ r += q.r;
+ v += q.v;
+ return *this;
+}
+
+template<class T>
+inline const Quat<T>& Quat<T>::operator-= (const Quat<T>& q)
+{
+ r -= q.r;
+ v -= q.v;
+ return *this;
+}
+template<class T>
+inline T& Quat<T>::operator[] (int index)
+{
+ return index ? v[index-1] : r;
+}
+
+template<class T>
+inline T Quat<T>::operator[] (int index) const
+{
+ return index ? v[index-1] : r;
+}
+
+template <class T>
+template <class S>
+inline bool
+Quat<T>::operator == (const Quat<S> &q) const
+{
+ return r == q.r && v == q.v;
+}
+
+template <class T>
+template <class S>
+inline bool
+Quat<T>::operator != (const Quat<S> &q) const
+{
+ return r != q.r || v != q.v;
+}
+
+template<class T>
+inline T operator^ (const Quat<T>& q1,const Quat<T>& q2)
+{
+ return q1.r * q2.r + (q1.v ^ q2.v);
+}
+
+template <class T>
+inline T Quat<T>::length() const
+{
+ return Math<T>::sqrt( r * r + (v ^ v) );
+}
+
+template <class T>
+inline Quat<T>& Quat<T>::normalize()
+{
+ if ( T l = length() ) { r /= l; v /= l; }
+ else { r = 1; v = Vec3<T>(0); }
+ return *this;
+}
+
+template <class T>
+inline Quat<T> Quat<T>::normalized() const
+{
+ if ( T l = length() ) return Quat( r / l, v / l );
+ return Quat();
+}
+
+template<class T>
+inline Quat<T> Quat<T>::inverse() const
+{
+ // 1 Q*
+ // - = ---- where Q* is conjugate (operator~)
+ // Q Q* Q and (Q* Q) == Q ^ Q (4D dot)
+
+ T qdot = *this ^ *this;
+ return Quat( r / qdot, -v / qdot );
+}
+
+template<class T>
+inline Quat<T>& Quat<T>::invert()
+{
+ T qdot = (*this) ^ (*this);
+ r /= qdot;
+ v = -v / qdot;
+ return *this;
+}
+
+template<class T>
+Quat<T>
+slerp(const Quat<T> &q1,const Quat<T> &q2, T t)
+{
+ //
+ // Spherical linear interpolation.
+ //
+ // NOTE: Assumes q1 and q2 are normalized and that 0 <= t <= 1.
+ //
+ // This method does *not* interpolate along the shortest arc
+ // between q1 and q2. If you desire interpolation along the
+ // shortest arc, then consider flipping the second quaternion
+ // explicitly before calling slerp. The implementation of squad()
+ // depends on a slerp() that interpolates as is, without the
+ // automatic flipping.
+ //
+
+ T cosomega = q1 ^ q2;
+ if (cosomega >= (T) 1.0)
+ {
+ //
+ // Special case: q1 and q2 are the same, so just return one of them.
+ // This also catches the case where cosomega is very slightly > 1.0
+ //
+
+ return q1;
+ }
+
+ T sinomega = Math<T>::sqrt (1 - cosomega * cosomega);
+
+ Quat<T> result;
+
+ if (sinomega * limits<T>::max() > 1)
+ {
+ T omega = Math<T>::acos (cosomega);
+ T s1 = Math<T>::sin ((1.0 - t) * omega) / sinomega;
+ T s2 = Math<T>::sin (t * omega) / sinomega;
+
+ result = s1 * q1 + s2 * q2;
+ }
+ else if (cosomega > 0)
+ {
+ //
+ // omega == 0
+ //
+
+ T s1 = 1.0 - t;
+ T s2 = t;
+
+ result = s1 * q1 + s2 * q2;
+ }
+ else
+ {
+ //
+ // omega == -pi
+ //
+
+ result.v.x = - q1.v.y;
+ result.v.y = q1.v.x;
+ result.v.z = - q1.r;
+ result.r = q1.v.z;
+
+ T s1 = Math<T>::sin ((0.5 - t) * M_PI);
+ T s2 = Math<T>::sin (t * M_PI);
+
+ result = s1 * q1 + s2 * result;
+ }
+
+ return result;
+}
+
+template<class T>
+Quat<T> spline(const Quat<T> &q0, const Quat<T> &q1,
+ const Quat<T> &q2, const Quat<T> &q3,
+ T t)
+{
+ // Spherical Cubic Spline Interpolation -
+ // from Advanced Animation and Rendering
+ // Techniques by Watt and Watt, Page 366:
+ // A spherical curve is constructed using three
+ // spherical linear interpolations of a quadrangle
+ // of unit quaternions: q1, qa, qb, q2.
+ // Given a set of quaternion keys: q0, q1, q2, q3,
+ // this routine does the interpolation between
+ // q1 and q2 by constructing two intermediate
+ // quaternions: qa and qb. The qa and qb are
+ // computed by the intermediate function to
+ // guarantee the continuity of tangents across
+ // adjacent cubic segments. The qa represents in-tangent
+ // for q1 and the qb represents the out-tangent for q2.
+ //
+ // The q1 q2 is the cubic segment being interpolated.
+ // The q0 is from the previous adjacent segment and q3 is
+ // from the next adjacent segment. The q0 and q3 are used
+ // in computing qa and qb.
+ //
+
+ Quat<T> qa = intermediate (q0, q1, q2);
+ Quat<T> qb = intermediate (q1, q2, q3);
+ Quat<T> result = squad(q1, qa, qb, q2, t);
+
+ return result;
+}
+
+template<class T>
+Quat<T> squad(const Quat<T> &q1, const Quat<T> &qa,
+ const Quat<T> &qb, const Quat<T> &q2,
+ T t)
+{
+ // Spherical Quadrangle Interpolation -
+ // from Advanced Animation and Rendering
+ // Techniques by Watt and Watt, Page 366:
+ // It constructs a spherical cubic interpolation as
+ // a series of three spherical linear interpolations
+ // of a quadrangle of unit quaternions.
+ //
+
+ Quat<T> r1 = slerp(q1, q2, t);
+ Quat<T> r2 = slerp(qa, qb, t);
+ Quat<T> result = slerp(r1, r2, 2*t*(1-t));
+
+ return result;
+}
+
+template<class T>
+Quat<T> intermediate(const Quat<T> &q0, const Quat<T> &q1, const Quat<T> &q2)
+{
+ // From advanced Animation and Rendering
+ // Techniques by Watt and Watt, Page 366:
+ // computing the inner quadrangle
+ // points (qa and qb) to guarantee tangent
+ // continuity.
+ //
+ Quat<T> q1inv = q1.inverse();
+ Quat<T> c1 = q1inv*q2;
+ Quat<T> c2 = q1inv*q0;
+ Quat<T> c3 = (T) (-0.25) * (c2.log() + c1.log());
+ Quat<T> qa = q1 * c3.exp();
+ qa.normalize();
+ return qa;
+}
+
+template <class T>
+inline Quat<T> Quat<T>::log() const
+{
+ //
+ // For unit quaternion, from Advanced Animation and
+ // Rendering Techniques by Watt and Watt, Page 366:
+ //
+
+ T theta = Math<T>::acos (std::min (r, (T) 1.0));
+ if (theta == 0)
+ return Quat<T> (0, v);
+
+ T sintheta = Math<T>::sin (theta);
+
+ T k;
+ if (abs (sintheta) < 1 && abs (theta) >= limits<T>::max() * abs (sintheta))
+ k = 0;
+ else
+ k = theta / sintheta;
+
+ return Quat<T> ((T) 0, v.x * k, v.y * k, v.z * k);
+}
+
+template <class T>
+inline Quat<T> Quat<T>::exp() const
+{
+ //
+ // For pure quaternion (zero scalar part):
+ // from Advanced Animation and Rendering
+ // Techniques by Watt and Watt, Page 366:
+ //
+
+ T theta = v.length();
+ T sintheta = Math<T>::sin (theta);
+
+ T k;
+ if (abs (theta) < 1 && abs (sintheta) >= limits<T>::max() * abs (theta))
+ k = 0;
+ else
+ k = sintheta / theta;
+
+ T costheta = Math<T>::cos (theta);
+
+ return Quat<T> (costheta, v.x * k, v.y * k, v.z * k);
+}
+
+template <class T>
+inline T Quat<T>::angle() const
+{
+ return 2.0*Math<T>::acos(r);
+}
+
+template <class T>
+inline Vec3<T> Quat<T>::axis() const
+{
+ return v.normalized();
+}
+
+template <class T>
+inline Quat<T>& Quat<T>::setAxisAngle(const Vec3<T>& axis, T radians)
+{
+ r = Math<T>::cos(radians/2);
+ v = axis.normalized() * Math<T>::sin(radians/2);
+ return *this;
+}
+
+
+template <class T>
+Quat<T>&
+Quat<T>::setRotation(const Vec3<T>& from, const Vec3<T>& to)
+{
+ //
+ // Ported from SbRotation
+ //
+
+ T cost = from.dot(to) / Math<T>::sqrt(from.dot(from) * to.dot(to));
+
+ // check for degeneracies
+ if (cost > 0.99999)
+ {
+ //
+ // Vectors are parallel.
+ //
+
+ r = 1.0;
+ v = Vec3<T>(0);
+ }
+ else if (cost < -0.99999)
+ {
+ //
+ // Vectors are opposite. Find an axis to rotate around,
+ // which should be perpendicular to the original axis.
+ //
+
+ Vec3<T> frm = from.normalized();
+ v = frm.cross(Vec3<T>(1, 0, 0));
+ if (v.length() < 0.00001)
+ v = frm.cross(Vec3<T>(0, 1, 0));
+ r = 0;
+ v.normalize();
+ }
+ else
+ {
+ //
+ // Use half-angle formulae:
+ // cos^2 t = ( 1 + cos (2t) ) / 2
+ // w part is cosine of half the rotation angle
+ //
+
+ r = Math<T>::sqrt(0.5 * (1.0 + cost));
+
+ //
+ // sin^2 t = ( 1 - cos (2t) ) / 2
+ // Do the normalization of the axis vector at the same time so
+ // we only call sqrt once.
+ //
+
+ v = from.cross(to);
+ v *= Math<T>::sqrt((0.5 * (1.0 - cost))/(v.dot(v)));
+ }
+
+ return *this;
+}
+
+template<class T>
+Matrix33<T> Quat<T>::toMatrix33() const
+{
+ return Matrix33<T>(1. - 2.0 * (v.y * v.y + v.z * v.z),
+ 2.0 * (v.x * v.y + v.z * r),
+ 2.0 * (v.z * v.x - v.y * r),
+
+ 2.0 * (v.x * v.y - v.z * r),
+ 1. - 2.0 * (v.z * v.z + v.x * v.x),
+ 2.0 * (v.y * v.z + v.x * r),
+
+ 2.0 * (v.z * v.x + v.y * r),
+ 2.0 * (v.y * v.z - v.x * r),
+ 1. - 2.0 * (v.y * v.y + v.x * v.x));
+}
+
+template<class T>
+Matrix44<T> Quat<T>::toMatrix44() const
+{
+ return Matrix44<T>(1. - 2.0 * (v.y * v.y + v.z * v.z),
+ 2.0 * (v.x * v.y + v.z * r),
+ 2.0 * (v.z * v.x - v.y * r),
+ 0.,
+ 2.0 * (v.x * v.y - v.z * r),
+ 1. - 2.0 * (v.z * v.z + v.x * v.x),
+ 2.0 * (v.y * v.z + v.x * r),
+ 0.,
+ 2.0 * (v.z * v.x + v.y * r),
+ 2.0 * (v.y * v.z - v.x * r),
+ 1. - 2.0 * (v.y * v.y + v.x * v.x),
+ 0.,
+ 0.,
+ 0.,
+ 0.,
+ 1.0 );
+}
+
+
+template<class T>
+inline Matrix33<T> operator* (const Matrix33<T> &M, const Quat<T> &q)
+{
+ return M * q.toMatrix33();
+}
+
+template<class T>
+inline Matrix33<T> operator* (const Quat<T> &q, const Matrix33<T> &M)
+{
+ return q.toMatrix33() * M;
+}
+
+template<class T>
+std::ostream& operator<< (std::ostream &o, const Quat<T> &q)
+{
+ return o << "(" << q.r
+ << " " << q.v.x
+ << " " << q.v.y
+ << " " << q.v.z
+ << ")";
+
+}
+
+template<class T>
+inline Quat<T> operator* (const Quat<T>& q1, const Quat<T>& q2)
+{
+ // (S1+V1) (S2+V2) = S1 S2 - V1.V2 + S1 V2 + V1 S2 + V1 x V2
+ return Quat<T>( q1.r * q2.r - (q1.v ^ q2.v),
+ q1.r * q2.v + q1.v * q2.r + q1.v % q2.v );
+}
+
+template<class T>
+inline Quat<T> operator/ (const Quat<T>& q1, const Quat<T>& q2)
+{
+ return q1 * q2.inverse();
+}
+
+template<class T>
+inline Quat<T> operator/ (const Quat<T>& q,T t)
+{
+ return Quat<T>(q.r/t,q.v/t);
+}
+
+template<class T>
+inline Quat<T> operator* (const Quat<T>& q,T t)
+{
+ return Quat<T>(q.r*t,q.v*t);
+}
+
+template<class T>
+inline Quat<T> operator* (T t, const Quat<T>& q)
+{
+ return Quat<T>(q.r*t,q.v*t);
+}
+
+template<class T>
+inline Quat<T> operator+ (const Quat<T>& q1, const Quat<T>& q2)
+{
+ return Quat<T>( q1.r + q2.r, q1.v + q2.v );
+}
+
+template<class T>
+inline Quat<T> operator- (const Quat<T>& q1, const Quat<T>& q2)
+{
+ return Quat<T>( q1.r - q2.r, q1.v - q2.v );
+}
+
+template<class T>
+inline Quat<T> operator~ (const Quat<T>& q)
+{
+ return Quat<T>( q.r, -q.v ); // conjugate: (S+V)* = S-V
+}
+
+template<class T>
+inline Quat<T> operator- (const Quat<T>& q)
+{
+ return Quat<T>( -q.r, -q.v );
+}
+
+#if (defined _WIN32 || defined _WIN64) && defined _MSC_VER
+#pragma warning(default:4244)
+#endif
+
+} // namespace Imath
+
+#endif