964 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			964 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| ///////////////////////////////////////////////////////////////////////////
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| //
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| // Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
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| // Digital Ltd. LLC
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| //
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| // All rights reserved.
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| //
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| // Redistribution and use in source and binary forms, with or without
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| // modification, are permitted provided that the following conditions are
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| // met:
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| // *       Redistributions of source code must retain the above copyright
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| // notice, this list of conditions and the following disclaimer.
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| // *       Redistributions in binary form must reproduce the above
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| // copyright notice, this list of conditions and the following disclaimer
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| // in the documentation and/or other materials provided with the
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| // distribution.
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| // *       Neither the name of Industrial Light & Magic nor the names of
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| // its contributors may be used to endorse or promote products derived
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| // from this software without specific prior written permission.
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| //
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| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| //
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| ///////////////////////////////////////////////////////////////////////////
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| 
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| 
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| 
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| #ifndef INCLUDED_IMATHQUAT_H
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| #define INCLUDED_IMATHQUAT_H
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| 
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| //----------------------------------------------------------------------
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| //
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| //	template class Quat<T>
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| //
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| //	"Quaternions came from Hamilton ... and have been an unmixed
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| //	evil to those who have touched them in any way. Vector is a
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| //	useless survival ... and has never been of the slightest use
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| //	to any creature."
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| //
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| //	    - Lord Kelvin
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| //
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| //	This class implements the quaternion numerical type -- you
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| //      will probably want to use this class to represent orientations
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| //	in R3 and to convert between various euler angle reps. You
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| //	should probably use Imath::Euler<> for that.
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| //
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| //----------------------------------------------------------------------
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| 
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| #include "ImathExc.h"
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| #include "ImathMatrix.h"
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| 
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| #include <iostream>
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| 
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| namespace Imath {
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| 
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| #if (defined _WIN32 || defined _WIN64) && defined _MSC_VER
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| // Disable MS VC++ warnings about conversion from double to float
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| #pragma warning(disable:4244)
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| #endif
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| 
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| template <class T>
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| class Quat
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| {
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|   public:
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| 
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|     T			r;	    // real part
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|     Vec3<T>		v;	    // imaginary vector
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| 
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| 
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|     //-----------------------------------------------------
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|     //	Constructors - default constructor is identity quat
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|     //-----------------------------------------------------
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| 
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|     Quat ();
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| 
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|     template <class S>
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|     Quat (const Quat<S> &q);
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| 
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|     Quat (T s, T i, T j, T k);
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| 
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|     Quat (T s, Vec3<T> d);
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| 
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|     static Quat<T> identity ();
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| 
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| 
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|     //-------------------------------------------------
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|     //	Basic Algebra - Operators and Methods
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|     //  The operator return values are *NOT* normalized
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|     //
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|     //  operator^ and euclideanInnnerProduct() both
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|     //            implement the 4D dot product
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|     //
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|     //  operator/ uses the inverse() quaternion
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|     //
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|     //	operator~ is conjugate -- if (S+V) is quat then
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|     //		  the conjugate (S+V)* == (S-V)
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|     //
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|     //  some operators (*,/,*=,/=) treat the quat as
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|     //	a 4D vector when one of the operands is scalar
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|     //-------------------------------------------------
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| 
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|     const Quat<T> &	operator =	(const Quat<T> &q);
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|     const Quat<T> &	operator *=	(const Quat<T> &q);
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|     const Quat<T> &	operator *=	(T t);
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|     const Quat<T> &	operator /=	(const Quat<T> &q);
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|     const Quat<T> &	operator /=	(T t);
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|     const Quat<T> &	operator +=	(const Quat<T> &q);
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|     const Quat<T> &	operator -=	(const Quat<T> &q);
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|     T &			operator []	(int index);	// as 4D vector
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|     T			operator []	(int index) const;
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| 
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|     template <class S> bool operator == (const Quat<S> &q) const;
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|     template <class S> bool operator != (const Quat<S> &q) const;
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| 
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|     Quat<T> &		invert ();		// this -> 1 / this
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|     Quat<T>		inverse () const;
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|     Quat<T> &		normalize ();		// returns this
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|     Quat<T>		normalized () const;
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|     T			length () const;	// in R4
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|     Vec3<T>             rotateVector(const Vec3<T> &original) const;
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|     T                   euclideanInnerProduct(const Quat<T> &q) const;
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| 
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|     //-----------------------
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|     //	Rotation conversion
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|     //-----------------------
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| 
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|     Quat<T> &		setAxisAngle (const Vec3<T> &axis, T radians);
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| 
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|     Quat<T> &		setRotation (const Vec3<T> &fromDirection,
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|                      const Vec3<T> &toDirection);
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| 
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|     T			angle () const;
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|     Vec3<T>		axis () const;
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| 
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|     Matrix33<T>		toMatrix33 () const;
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|     Matrix44<T>		toMatrix44 () const;
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| 
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|     Quat<T>		log () const;
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|     Quat<T>		exp () const;
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| 
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| 
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|   private:
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| 
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|     void		setRotationInternal (const Vec3<T> &f0,
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|                          const Vec3<T> &t0,
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|                          Quat<T> &q);
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| };
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| 
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| 
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| template<class T>
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| Quat<T>			slerp (const Quat<T> &q1, const Quat<T> &q2, T t);
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| 
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| template<class T>
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| Quat<T>			slerpShortestArc
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|                               (const Quat<T> &q1, const Quat<T> &q2, T t);
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| 
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| 
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| template<class T>
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| Quat<T>			squad (const Quat<T> &q1, const Quat<T> &q2,
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|                    const Quat<T> &qa, const Quat<T> &qb, T t);
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| 
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| template<class T>
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| void			intermediate (const Quat<T> &q0, const Quat<T> &q1,
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|                       const Quat<T> &q2, const Quat<T> &q3,
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|                       Quat<T> &qa, Quat<T> &qb);
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| 
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| template<class T>
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| Matrix33<T>		operator * (const Matrix33<T> &M, const Quat<T> &q);
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| 
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| template<class T>
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| Matrix33<T>		operator * (const Quat<T> &q, const Matrix33<T> &M);
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| 
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| template<class T>
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| std::ostream &		operator << (std::ostream &o, const Quat<T> &q);
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| 
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| template<class T>
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| Quat<T>			operator * (const Quat<T> &q1, const Quat<T> &q2);
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| 
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| template<class T>
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| Quat<T>			operator / (const Quat<T> &q1, const Quat<T> &q2);
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| 
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| template<class T>
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| Quat<T>			operator / (const Quat<T> &q, T t);
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| 
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| template<class T>
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| Quat<T>			operator * (const Quat<T> &q, T t);
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| 
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| template<class T>
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| Quat<T>			operator * (T t, const Quat<T> &q);
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| 
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| template<class T>
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| Quat<T>			operator + (const Quat<T> &q1, const Quat<T> &q2);
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| 
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| template<class T>
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| Quat<T>			operator - (const Quat<T> &q1, const Quat<T> &q2);
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| 
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| template<class T>
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| Quat<T>			operator ~ (const Quat<T> &q);
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| 
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| template<class T>
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| Quat<T>			operator - (const Quat<T> &q);
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| 
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| template<class T>
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| Vec3<T>			operator * (const Vec3<T> &v, const Quat<T> &q);
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| 
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| 
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| //--------------------
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| // Convenient typedefs
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| //--------------------
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| 
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| typedef Quat<float>	Quatf;
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| typedef Quat<double>	Quatd;
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| 
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| 
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| //---------------
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| // Implementation
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| //---------------
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| 
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| template<class T>
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| inline
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| Quat<T>::Quat (): r (1), v (0, 0, 0)
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| {
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|     // empty
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| }
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| 
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| 
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| template<class T>
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| template <class S>
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| inline
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| Quat<T>::Quat (const Quat<S> &q): r (q.r), v (q.v)
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| {
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|     // empty
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| }
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| 
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| 
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| template<class T>
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| inline
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| Quat<T>::Quat (T s, T i, T j, T k): r (s), v (i, j, k)
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| {
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|     // empty
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| }
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| 
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| 
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| template<class T>
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| inline
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| Quat<T>::Quat (T s, Vec3<T> d): r (s), v (d)
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| {
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|     // empty
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| }
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| 
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| 
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| template<class T>
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| inline Quat<T>
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| Quat<T>::identity ()
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| {
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|     return Quat<T>();
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| }
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator = (const Quat<T> &q)
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| {
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|     r = q.r;
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|     v = q.v;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator *= (const Quat<T> &q)
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| {
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|     T rtmp = r * q.r - (v ^ q.v);
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|     v = r * q.v + v * q.r + v % q.v;
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|     r = rtmp;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator *= (T t)
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| {
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|     r *= t;
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|     v *= t;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator /= (const Quat<T> &q)
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| {
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|     *this = *this * q.inverse();
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator /= (T t)
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| {
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|     r /= t;
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|     v /= t;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator += (const Quat<T> &q)
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| {
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|     r += q.r;
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|     v += q.v;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline const Quat<T> &
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| Quat<T>::operator -= (const Quat<T> &q)
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| {
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|     r -= q.r;
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|     v -= q.v;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline T &
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| Quat<T>::operator [] (int index)
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| {
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|     return index ? v[index - 1] : r;
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| }
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| 
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| 
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| template<class T>
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| inline T
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| Quat<T>::operator [] (int index) const
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| {
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|     return index ? v[index - 1] : r;
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| }
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| 
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| 
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| template <class T>
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| template <class S>
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| inline bool
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| Quat<T>::operator == (const Quat<S> &q) const
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| {
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|     return r == q.r && v == q.v;
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| }
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| 
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| 
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| template <class T>
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| template <class S>
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| inline bool
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| Quat<T>::operator != (const Quat<S> &q) const
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| {
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|     return r != q.r || v != q.v;
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| }
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| 
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| 
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| template<class T>
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| inline T
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| operator ^ (const Quat<T>& q1 ,const Quat<T>& q2)
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| {
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|     return q1.r * q2.r + (q1.v ^ q2.v);
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| }
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| 
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| 
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| template <class T>
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| inline T
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| Quat<T>::length () const
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| {
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|     return Math<T>::sqrt (r * r + (v ^ v));
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| }
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| 
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| 
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| template <class T>
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| inline Quat<T> &
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| Quat<T>::normalize ()
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| {
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|     if (T l = length())
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|     {
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|     r /= l;
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|     v /= l;
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|     }
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|     else
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|     {
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|     r = 1;
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|     v = Vec3<T> (0);
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|     }
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| 
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|     return *this;
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| }
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| 
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| 
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| template <class T>
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| inline Quat<T>
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| Quat<T>::normalized () const
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| {
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|     if (T l = length())
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|     return Quat (r / l, v / l);
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| 
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|     return Quat();
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| }
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| 
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| 
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| template<class T>
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| inline Quat<T>
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| Quat<T>::inverse () const
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| {
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|     //
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|     // 1    Q*
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|     // - = ----   where Q* is conjugate (operator~)
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|     // Q   Q* Q   and (Q* Q) == Q ^ Q (4D dot)
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|     //
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| 
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|     T qdot = *this ^ *this;
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|     return Quat (r / qdot, -v / qdot);
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| }
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| 
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| 
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| template<class T>
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| inline Quat<T> &
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| Quat<T>::invert ()
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| {
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|     T qdot = (*this) ^ (*this);
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|     r /= qdot;
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|     v = -v / qdot;
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|     return *this;
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| }
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| 
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| 
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| template<class T>
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| inline Vec3<T>
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| Quat<T>::rotateVector(const Vec3<T>& original) const
 | |
| {
 | |
|     //
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|     // Given a vector p and a quaternion q (aka this),
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|     // calculate p' = qpq*
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|     //
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|     // Assumes unit quaternions (because non-unit
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|     // quaternions cannot be used to rotate vectors
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|     // anyway).
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|     //
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| 
 | |
|     Quat<T> vec (0, original);  // temporarily promote grade of original
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|     Quat<T> inv (*this);
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|     inv.v *= -1;                // unit multiplicative inverse
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|     Quat<T> result = *this * vec * inv;
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|     return result.v;
 | |
| }
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| 
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| 
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| template<class T>
 | |
| inline T
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| Quat<T>::euclideanInnerProduct (const Quat<T> &q) const
 | |
| {
 | |
|     return r * q.r + v.x * q.v.x + v.y * q.v.y + v.z * q.v.z;
 | |
| }
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| 
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| 
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| template<class T>
 | |
| T
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| angle4D (const Quat<T> &q1, const Quat<T> &q2)
 | |
| {
 | |
|     //
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|     // Compute the angle between two quaternions,
 | |
|     // interpreting the quaternions as 4D vectors.
 | |
|     //
 | |
| 
 | |
|     Quat<T> d = q1 - q2;
 | |
|     T lengthD = Math<T>::sqrt (d ^ d);
 | |
| 
 | |
|     Quat<T> s = q1 + q2;
 | |
|     T lengthS = Math<T>::sqrt (s ^ s);
 | |
| 
 | |
|     return 2 * Math<T>::atan2 (lengthD, lengthS);
 | |
| }
 | |
| 
 | |
| 
 | |
| template<class T>
 | |
| Quat<T>
 | |
| slerp (const Quat<T> &q1, const Quat<T> &q2, T t)
 | |
| {
 | |
|     //
 | |
|     // Spherical linear interpolation.
 | |
|     // Assumes q1 and q2 are normalized and that q1 != -q2.
 | |
|     //
 | |
|     // This method does *not* interpolate along the shortest
 | |
|     // arc between q1 and q2.  If you desire interpolation
 | |
|     // along the shortest arc, and q1^q2 is negative, then
 | |
|     // consider calling slerpShortestArc(), below, or flipping
 | |
|     // the second quaternion explicitly.
 | |
|     //
 | |
|     // The implementation of squad() depends on a slerp()
 | |
|     // that interpolates as is, without the automatic
 | |
|     // flipping.
 | |
|     //
 | |
|     // Don Hatch explains the method we use here on his
 | |
|     // web page, The Right Way to Calculate Stuff, at
 | |
|     // http://www.plunk.org/~hatch/rightway.php
 | |
|     //
 | |
| 
 | |
|     T a = angle4D (q1, q2);
 | |
|     T s = 1 - t;
 | |
| 
 | |
|     Quat<T> q = sinx_over_x (s * a) / sinx_over_x (a) * s * q1 +
 | |
|             sinx_over_x (t * a) / sinx_over_x (a) * t * q2;
 | |
| 
 | |
|     return q.normalized();
 | |
| }
 | |
| 
 | |
| 
 | |
| template<class T>
 | |
| Quat<T>
 | |
| slerpShortestArc (const Quat<T> &q1, const Quat<T> &q2, T t)
 | |
| {
 | |
|     //
 | |
|     // Spherical linear interpolation along the shortest
 | |
|     // arc from q1 to either q2 or -q2, whichever is closer.
 | |
|     // Assumes q1 and q2 are unit quaternions.
 | |
|     //
 | |
| 
 | |
|     if ((q1 ^ q2) >= 0)
 | |
|         return slerp (q1, q2, t);
 | |
|     else
 | |
|         return slerp (q1, -q2, t);
 | |
| }
 | |
| 
 | |
| 
 | |
| 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 = 1;
 | |
|     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 = 1;
 | |
|     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 * Math<T>::atan2 (v.length(), 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)
 | |
| {
 | |
|     //
 | |
|     // Create a quaternion that rotates vector from into vector to,
 | |
|     // such that the rotation is around an axis that is the cross
 | |
|     // product of from and to.
 | |
|     //
 | |
|     // This function calls function setRotationInternal(), which is
 | |
|     // numerically accurate only for rotation angles that are not much
 | |
|     // greater than pi/2.  In order to achieve good accuracy for angles
 | |
|     // greater than pi/2, we split large angles in half, and rotate in
 | |
|     // two steps.
 | |
|     //
 | |
| 
 | |
|     //
 | |
|     // Normalize from and to, yielding f0 and t0.
 | |
|     //
 | |
| 
 | |
|     Vec3<T> f0 = from.normalized();
 | |
|     Vec3<T> t0 = to.normalized();
 | |
| 
 | |
|     if ((f0 ^ t0) >= 0)
 | |
|     {
 | |
|     //
 | |
|     // The rotation angle is less than or equal to pi/2.
 | |
|     //
 | |
| 
 | |
|     setRotationInternal (f0, t0, *this);
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|     //
 | |
|     // The angle is greater than pi/2.  After computing h0,
 | |
|     // which is halfway between f0 and t0, we rotate first
 | |
|     // from f0 to h0, then from h0 to t0.
 | |
|     //
 | |
| 
 | |
|     Vec3<T> h0 = (f0 + t0).normalized();
 | |
| 
 | |
|     if ((h0 ^ h0) != 0)
 | |
|     {
 | |
|         setRotationInternal (f0, h0, *this);
 | |
| 
 | |
|         Quat<T> q;
 | |
|         setRotationInternal (h0, t0, q);
 | |
| 
 | |
|         *this *= q;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         //
 | |
|         // f0 and t0 point in exactly opposite directions.
 | |
|         // Pick an arbitrary axis that is orthogonal to f0,
 | |
|         // and rotate by pi.
 | |
|         //
 | |
| 
 | |
|         r = T (0);
 | |
| 
 | |
|         Vec3<T> f02 = f0 * f0;
 | |
| 
 | |
|         if (f02.x <= f02.y && f02.x <= f02.z)
 | |
|         v = (f0 % Vec3<T> (1, 0, 0)).normalized();
 | |
|         else if (f02.y <= f02.z)
 | |
|         v = (f0 % Vec3<T> (0, 1, 0)).normalized();
 | |
|         else
 | |
|         v = (f0 % Vec3<T> (0, 0, 1)).normalized();
 | |
|     }
 | |
|     }
 | |
| 
 | |
|     return *this;
 | |
| }
 | |
| 
 | |
| 
 | |
| template <class T>
 | |
| void
 | |
| Quat<T>::setRotationInternal (const Vec3<T> &f0, const Vec3<T> &t0, Quat<T> &q)
 | |
| {
 | |
|     //
 | |
|     // The following is equivalent to setAxisAngle(n,2*phi),
 | |
|     // where the rotation axis, n, is orthogonal to the f0 and
 | |
|     // t0 vectors, and 2*phi is the angle between f0 and t0.
 | |
|     //
 | |
|     // This function is called by setRotation(), above; it assumes
 | |
|     // that f0 and t0 are normalized and that the angle between
 | |
|     // them is not much greater than pi/2.  This function becomes
 | |
|     // numerically inaccurate if f0 and t0 point into nearly
 | |
|     // opposite directions.
 | |
|     //
 | |
| 
 | |
|     //
 | |
|     // Find a normalized vector, h0, that is halfway between f0 and t0.
 | |
|     // The angle between f0 and h0 is phi.
 | |
|     //
 | |
| 
 | |
|     Vec3<T> h0 = (f0 + t0).normalized();
 | |
| 
 | |
|     //
 | |
|     // Store the rotation axis and rotation angle.
 | |
|     //
 | |
| 
 | |
|     q.r = f0 ^ h0;	//  f0 ^ h0 == cos (phi)
 | |
|     q.v = f0 % h0;	// (f0 % h0).length() == sin (phi)
 | |
| }
 | |
| 
 | |
| 
 | |
| template<class T>
 | |
| Matrix33<T>
 | |
| Quat<T>::toMatrix33() const
 | |
| {
 | |
|     return Matrix33<T> (1 - 2 * (v.y * v.y + v.z * v.z),
 | |
|                 2 * (v.x * v.y + v.z * r),
 | |
|                 2 * (v.z * v.x - v.y * r),
 | |
| 
 | |
|                 2 * (v.x * v.y - v.z * r),
 | |
|                 1 - 2 * (v.z * v.z + v.x * v.x),
 | |
|                 2 * (v.y * v.z + v.x * r),
 | |
| 
 | |
|                 2 * (v.z * v.x + v.y * r),
 | |
|                 2 * (v.y * v.z - v.x * r),
 | |
|                 1 - 2 * (v.y * v.y + v.x * v.x));
 | |
| }
 | |
| 
 | |
| template<class T>
 | |
| Matrix44<T>
 | |
| Quat<T>::toMatrix44() const
 | |
| {
 | |
|     return Matrix44<T> (1 - 2 * (v.y * v.y + v.z * v.z),
 | |
|                 2 * (v.x * v.y + v.z * r),
 | |
|                 2 * (v.z * v.x - v.y * r),
 | |
|                 0,
 | |
|                 2 * (v.x * v.y - v.z * r),
 | |
|                 1 - 2 * (v.z * v.z + v.x * v.x),
 | |
|                 2 * (v.y * v.z + v.x * r),
 | |
|                 0,
 | |
|                 2 * (v.z * v.x + v.y * r),
 | |
|                 2 * (v.y * v.z - v.x * r),
 | |
|                 1 - 2 * (v.y * v.y + v.x * v.x),
 | |
|                 0,
 | |
|                 0,
 | |
|                 0,
 | |
|                 0,
 | |
|                 1);
 | |
| }
 | |
| 
 | |
| 
 | |
| 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)
 | |
| {
 | |
|     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);
 | |
| }
 | |
| 
 | |
| 
 | |
| template<class T>
 | |
| inline Quat<T>
 | |
| operator - (const Quat<T> &q)
 | |
| {
 | |
|     return Quat<T> (-q.r, -q.v);
 | |
| }
 | |
| 
 | |
| 
 | |
| template<class T>
 | |
| inline Vec3<T>
 | |
| operator * (const Vec3<T> &v, const Quat<T> &q)
 | |
| {
 | |
|     Vec3<T> a = q.v % v;
 | |
|     Vec3<T> b = q.v % a;
 | |
|     return v + T (2) * (q.r * a + b);
 | |
| }
 | |
| 
 | |
| #if (defined _WIN32 || defined _WIN64) && defined _MSC_VER
 | |
| #pragma warning(default:4244)
 | |
| #endif
 | |
| 
 | |
| } // namespace Imath
 | |
| 
 | |
| #endif
 | 
