OpenSceneGraph/include/osg/Quat
2003-09-05 20:52:36 +00:00

299 lines
9.0 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library 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
* OpenSceneGraph Public License for more details.
*/
#ifndef OSG_QUAT
#define OSG_QUAT 1
#include <osg/Export>
#include <osg/Vec3>
#include <osg/Vec4>
namespace osg {
class Matrixf;
class Matrixd;
/** A quaternion class. It can be used to represent an orientation in 3D space.*/
class SG_EXPORT Quat
{
public:
/* ----------------------------------------------------------
DATA MEMBERS
The only data member is a
Vec4 which holds the elements
In other words, osg:Quat is composed of an osg::Vec4
The osg::Quat aggregates an osg::Vec4
These seem to be different jargon for the same thing :-)
---------------------------------------------------------- */
Vec4 _fv; // a four-vector
inline Quat(): _fv(0.0f,0.0f,0.0f,1.0f) {}
inline Quat( float x, float y, float z, float w ): _fv(x,y,z,w) {}
inline Quat( const Vec4& v ): _fv(v) {}
inline Quat( float angle, const Vec3& axis)
{
makeRotate(angle,axis);
}
inline Quat( float angle1, const Vec3& axis1,
float angle2, const Vec3& axis2,
float angle3, const Vec3& axis3)
{
makeRotate(angle1,axis1,angle2,axis2,angle3,axis3);
}
inline bool operator == (const Quat& rhs) const { return _fv==rhs._fv; }
inline bool operator != (const Quat& rhs) const { return _fv!=rhs._fv; }
inline bool operator < (const Quat& rhs) const { return _fv<rhs._fv; }
/* ----------------------------------
Methods to access data members
---------------------------------- */
inline Vec4& asVec4()
{
return _fv;
}
inline const Vec4& asVec4() const
{
return _fv;
}
inline const Vec3 asVec3() const
{
return Vec3(_fv[0], _fv[1], _fv[2]);
}
inline void set(float x, float y, float z, float w)
{
_fv.set(x,y,z,w);
}
inline void set(const osg::Vec4& v)
{
_fv = v;
}
void set(const Matrixf& matrix);
void set(const Matrixd& matrix);
void get(Matrixf& matrix) const;
void get(Matrixd& matrix) const;
inline float& operator [] (int i) { return _fv[i]; }
inline float operator [] (int i) const { return _fv[i]; }
inline float& x() { return _fv[0]; }
inline float& y() { return _fv[1]; }
inline float& z() { return _fv[2]; }
inline float& w() { return _fv[3]; }
inline float x() const { return _fv[0]; }
inline float y() const { return _fv[1]; }
inline float z() const { return _fv[2]; }
inline float w() const { return _fv[3]; }
/** return true if the Quat represents a zero rotation, and therefore can be ignored in computations.*/
bool zeroRotation() const { return _fv[0]==0.0f && _fv[1]==0.0f && _fv[2]==0.0f && _fv[3]==1.0f; }
/* -------------------------------------------------------------
BASIC ARITHMETIC METHODS
Implemented in terms of Vec4s. Some Vec4 operators, e.g.
operator* are not appropriate for quaternions (as
mathematical objects) so they are implemented differently.
Also define methods for conjugate and the multiplicative inverse.
------------------------------------------------------------- */
/// Multiply by scalar
inline const Quat operator * (float rhs) const
{
return Quat(_fv*rhs);
}
/// Unary multiply by scalar
inline Quat& operator *= (float rhs)
{
_fv*=rhs;
return *this; // enable nesting
}
/// Binary multiply
inline const Quat operator*(const Quat& rhs) const
{
return Quat( rhs._fv[3]*_fv[0] + rhs._fv[0]*_fv[3] + rhs._fv[1]*_fv[2] - rhs._fv[2]*_fv[1],
rhs._fv[3]*_fv[1] - rhs._fv[0]*_fv[2] + rhs._fv[1]*_fv[3] + rhs._fv[2]*_fv[0],
rhs._fv[3]*_fv[2] + rhs._fv[0]*_fv[1] - rhs._fv[1]*_fv[0] + rhs._fv[2]*_fv[3],
rhs._fv[3]*_fv[3] - rhs._fv[0]*_fv[0] - rhs._fv[1]*_fv[1] - rhs._fv[2]*_fv[2] );
}
/// Unary multiply
inline Quat& operator*=(const Quat& rhs)
{
float x = rhs._fv[3]*_fv[0] + rhs._fv[0]*_fv[3] + rhs._fv[1]*_fv[2] - rhs._fv[2]*_fv[1];
float y = rhs._fv[3]*_fv[1] - rhs._fv[0]*_fv[2] + rhs._fv[1]*_fv[3] + rhs._fv[2]*_fv[0];
float z = rhs._fv[3]*_fv[2] + rhs._fv[0]*_fv[1] - rhs._fv[1]*_fv[0] + rhs._fv[2]*_fv[3];
_fv[3] = rhs._fv[3]*_fv[3] - rhs._fv[0]*_fv[0] - rhs._fv[1]*_fv[1] - rhs._fv[2]*_fv[2];
_fv[2] = z;
_fv[1] = y;
_fv[0] = x;
return (*this); // enable nesting
}
/// Divide by scalar
inline const Quat operator / (float rhs) const
{
return Quat(_fv/rhs);
}
/// Unary divide by scalar
inline Quat& operator /= (float rhs)
{
_fv/=rhs;
return *this;
}
/// Binary divide
inline const Quat operator/(const Quat& denom) const
{
return ( (*this) * denom.inverse() );
}
/// Unary divide
inline Quat& operator/=(const Quat& denom)
{
(*this) = (*this) * denom.inverse();
return (*this); // enable nesting
}
/// Binary addition
inline const Quat operator + (const Quat& rhs) const
{
return Quat( _fv + rhs._fv );
}
/// Unary addition
inline Quat& operator += (const Quat& rhs)
{
_fv += rhs._fv;
return *this; // enable nesting
}
/// Binary subtraction
inline const Quat operator - (const Quat& rhs) const
{
return Quat( _fv - rhs._fv );
}
/// Unary subtraction
inline Quat& operator -= (const Quat& rhs)
{
_fv-=rhs._fv;
return *this; // enable nesting
}
/** Negation operator - returns the negative of the quaternion.
Basically just calls operator - () on the Vec4 */
inline const Quat operator - () const
{
return Quat ( -_fv );
}
/// Length of the quaternion = sqrt( vec . vec )
float length() const
{
return _fv.length();
}
/// Length of the quaternion = vec . vec
float length2() const
{
return _fv.length2();
}
/// Conjugate
inline Quat conj () const
{
return Quat( -_fv[0], -_fv[1], -_fv[2], _fv[3] );
}
/// Multiplicative inverse method: q^(-1) = q^*/(q.q^*)
inline const Quat inverse () const
{
return conj() / length2();
}
/* --------------------------------------------------------
METHODS RELATED TO ROTATIONS
Set a quaternion which will perform a rotation of an
angle around the axis given by the vector (x,y,z).
Should be written to also accept an angle and a Vec3?
Define Spherical Linear interpolation method also
Not inlined - see the Quat.cpp file for implementation
-------------------------------------------------------- */
void makeRotate( float angle,
float x, float y, float z );
void makeRotate ( float angle, const Vec3& vec );
void makeRotate ( float angle1, const Vec3& axis1,
float angle2, const Vec3& axis2,
float angle3, const Vec3& axis3);
/** Make a rotation Quat which will rotate vec1 to vec2.
Generally take adot product to get the angle between these
and then use a cross product to get the rotation axis
Watch out for the two special cases of when the vectors
are co-incident or opposite in direction.*/
void makeRotate( const Vec3& vec1, const Vec3& vec2 );
/** Return the angle and vector components represented by the quaternion.*/
void getRotate ( float& angle, float& x, float& y, float& z ) const;
/** Return the angle and vector represented by the quaternion.*/
void getRotate ( float& angle, Vec3& vec ) const;
/** Spherical Linear Interpolation.
As t goes from 0 to 1, the Quat object goes from "from" to "to". */
void slerp ( float t, const Quat& from, const Quat& to);
friend inline std::ostream& operator << (std::ostream& output, const Quat& vec);
protected:
}; // end of class prototype
inline std::ostream& operator << (std::ostream& output, const Quat& vec)
{
output << vec._fv[0] << " "
<< vec._fv[1] << " "
<< vec._fv[2] << " "
<< vec._fv[3];
return output; // to enable cascading
}
} // end of namespace
#endif