Class Quaterniond

    • Field Summary

      Fields 
      Modifier and Type Field Description
      double w  
      double x  
      double y  
      double z  
    • Constructor Summary

      Constructors 
      Constructor Description
      Quaterniond()  
      Quaterniond​(double x, double y, double z, double w)
      Constructor, sets the four components of the quaternion.
      Quaterniond​(com.badlogic.gdx.math.Quaternion quaternion)
      Constructor, sets the quaternion components from the given quaternion.
      Quaterniond​(Quaterniond quaternion)
      Constructor, sets the quaternion components from the given quaternion.
      Quaterniond​(Vector3d axis, double angle)
      Constructor, sets the quaternion from the given axis vector and the angle around that axis in degrees.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Quaterniond conjugate()
      Conjugate the quaternion.
      Quaterniond cpy()  
      double dot​(double x, double y, double z, double w)
      Get the dot product between this and the other quaternion (commutative).
      static double dot​(double x1, double y1, double z1, double w1, double x2, double y2, double z2, double w2)
      Get the dot product between the two quaternions (commutative).
      double dot​(Quaterniond other)
      Get the dot product between this and the other quaternion (commutative).
      boolean equals​(java.lang.Object obj)  
      double getAngle()
      Get the angle in degrees of the rotation this quaternion represents.
      double getAngleAround​(double axisX, double axisY, double axisZ)
      Get the angle in degrees of the rotation around the specified axis.
      double getAngleAround​(Vector3d axis)
      Get the angle in degrees of the rotation around the specified axis.
      double getAngleAroundRad​(double axisX, double axisY, double axisZ)
      Get the angle in radians of the rotation around the specified axis.
      double getAngleAroundRad​(Vector3d axis)
      Get the angle in radians of the rotation around the specified axis.
      double getAngleRad()
      Get the angle in radians of the rotation this quaternion represents.
      double getAxisAngle​(Vector3d axis)
      Get the axis angle representation of the rotation in degrees.
      double getAxisAngleRad​(Vector3d axis)
      Get the axis-angle representation of the rotation in radians.
      int getGimbalPole()
      Get the pole of the gimbal lock, if any.
      double getPitch()
      Get the pitch euler angle in degrees, which is the rotation around the x axis.
      double getPitchRad()
      Get the pitch euler angle in radians, which is the rotation around the x axis.
      double getRoll()
      Get the roll euler angle in degrees, which is the rotation around the z axis.
      double getRollRad()
      Get the roll euler angle in radians, which is the rotation around the z axis.
      void getSwingTwist​(double axisX, double axisY, double axisZ, Quaterniond swing, Quaterniond twist)
      Get the swing rotation and twist rotation for the specified axis.
      void getSwingTwist​(Vector3d axis, Quaterniond swing, Quaterniond twist)
      Get the swing rotation and twist rotation for the specified axis.
      double getYaw()
      Get the yaw euler angle in degrees, which is the rotation around the y axis.
      double getYawRad()
      Get the yaw euler angle in radians, which is the rotation around the y axis.
      int hashCode()  
      Quaterniond idt()
      Sets the quaternion to an identity Quaterniond
      Quaterniond inverse()
      Sets the value of this quaternion to the quaternion inverse of itself.
      boolean isIdentity()  
      boolean isIdentity​(double tolerance)  
      double len()  
      static double len​(double x, double y, double z, double w)  
      double len2()  
      static double len2​(double x, double y, double z, double w)  
      Quaterniond mul​(double scalar)
      Multiplies the components of this quaternion with the given scalar.
      Quaterniond mul​(double x, double y, double z, double w)
      Multiplies this quaternion with another one in the form of this = this * other
      Quaterniond mul​(Quaterniond other)
      Multiplies this quaternion with another one in the form of this = this * other
      Quaterniond mulAdd​(Quaterniond q, double s)
      Add quaternion q, scaled by s, to this quaternion (this = this + q * s)
      Quaterniond mulInverse​(Quaterniond q1)
      Multiplies this quaternion by the inverse of quaternion q1 and places the value into this quaternion.
      Quaterniond mulLeft​(double x, double y, double z, double w)
      Multiplies this quaternion with another one in the form of this = other * this
      Quaterniond mulLeft​(Quaterniond other)
      Multiplies this quaternion with another one in the form of this = other * this
      Quaterniond mulLeftInverse​(Quaterniond q1)
      Pre-multiplies this quaternion by the inverse of quaternion q and places the value into this quaternion.
      Quaterniond nor()
      Normalizes this quaternion to unit length
      Quaterniond set​(double x, double y, double z, double w)
      Sets the components of the quaternion
      Quaterniond set​(com.badlogic.gdx.math.Quaternion quaternion)
      Sets the quaternion components from the given quaternion.
      Quaterniond set​(Quaterniond quaternion)
      Sets the quaternion components from the given quaternion.
      Quaterniond set​(Vector3d axis, double angle)
      Sets the quaternion components from the given axis and angle around that axis.
      Quaterniond setEulerAngles​(double yaw, double pitch, double roll)
      Sets the quaternion to the given euler angles in degrees.
      Quaterniond setEulerAnglesRad​(double yaw, double pitch, double roll)
      Sets the quaternion to the given euler angles in radians.
      Quaterniond setFromAxes​(boolean normalizeAxes, double xx, double xy, double xz, double yx, double yy, double yz, double zx, double zy, double zz)
      Sets the Quaterniond from the given x-, y- and z-axis.
      Quaterniond setFromAxes​(double xx, double xy, double xz, double yx, double yy, double yz, double zx, double zy, double zz)
      Sets the Quaterniond from the given x-, y- and z-axis which have to be orthonormal.
      Quaterniond setFromAxis​(double x, double y, double z, double degrees)
      Sets the quaternion components from the given axis and angle around that axis.
      Quaterniond setFromAxis​(Vector3d axis, double degrees)
      Sets the quaternion components from the given axis and angle around that axis.
      Quaterniond setFromAxisRad​(double x, double y, double z, double radians)
      Sets the quaternion components from the given axis and angle around that axis.
      Quaterniond setFromAxisRad​(Vector3d axis, double radians)
      Sets the quaternion components from the given axis and angle around that axis.
      Quaterniond setFromCross​(double x1, double y1, double z1, double x2, double y2, double z2)
      Set this quaternion to the rotation between two vectors.
      Quaterniond setFromCross​(Vector3d v1, Vector3d v2)
      Set this quaternion to the rotation between two vectors.
      Quaterniond setFromMatrix​(boolean normalizeAxes, Matrix4d matrix)
      Sets the Quaterniond from the given matrix, optionally removing any scaling.
      Quaterniond setFromMatrix​(Matrix4d matrix)
      Sets the Quaterniond from the given rotation matrix, which must not contain scaling.
      Quaterniond slerp​(Quaterniond end, double alpha)
      Spherical linear interpolation between this quaternion and the other quaternion, based on the alpha value in the range [0,1].
      void toMatrix​(double[] matrix)
      Fills a 4x4 matrix with the rotation matrix represented by this quaternion.
      java.lang.String toString()  
      Vector3d transform​(Vector3d v)
      Transforms the given vector using this quaternion
      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, wait, wait, wait
    • Field Detail

      • x

        public double x
      • y

        public double y
      • z

        public double z
      • w

        public double w
    • Constructor Detail

      • Quaterniond

        public Quaterniond​(double x,
                           double y,
                           double z,
                           double w)
        Constructor, sets the four components of the quaternion.
        Parameters:
        x - The x-component
        y - The y-component
        z - The z-component
        w - The w-component
      • Quaterniond

        public Quaterniond()
      • Quaterniond

        public Quaterniond​(Quaterniond quaternion)
        Constructor, sets the quaternion components from the given quaternion.
        Parameters:
        quaternion - The quaternion to copy.
      • Quaterniond

        public Quaterniond​(com.badlogic.gdx.math.Quaternion quaternion)
        Constructor, sets the quaternion components from the given quaternion.
        Parameters:
        quaternion - The quaternion to copy.
      • Quaterniond

        public Quaterniond​(Vector3d axis,
                           double angle)
        Constructor, sets the quaternion from the given axis vector and the angle around that axis in degrees.
        Parameters:
        axis - The axis
        angle - The angle in degrees.
    • Method Detail

      • set

        public Quaterniond set​(double x,
                               double y,
                               double z,
                               double w)
        Sets the components of the quaternion
        Parameters:
        x - The x-component
        y - The y-component
        z - The z-component
        w - The w-component
        Returns:
        This quaternion for chaining
      • set

        public Quaterniond set​(Quaterniond quaternion)
        Sets the quaternion components from the given quaternion.
        Parameters:
        quaternion - The quaternion.
        Returns:
        This quaternion for chaining.
      • set

        public Quaterniond set​(com.badlogic.gdx.math.Quaternion quaternion)
        Sets the quaternion components from the given quaternion.
        Parameters:
        quaternion - The quaternion.
        Returns:
        This quaternion for chaining.
      • set

        public Quaterniond set​(Vector3d axis,
                               double angle)
        Sets the quaternion components from the given axis and angle around that axis.
        Parameters:
        axis - The axis
        angle - The angle in degrees
        Returns:
        This quaternion for chaining.
      • cpy

        public Quaterniond cpy()
        Returns:
        a copy of this quaternion
      • len

        public static final double len​(double x,
                                       double y,
                                       double z,
                                       double w)
        Returns:
        the euclidian length of the specified quaternion
      • len

        public double len()
        Returns:
        the euclidian length of this quaternion
      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object
      • setEulerAngles

        public Quaterniond setEulerAngles​(double yaw,
                                          double pitch,
                                          double roll)
        Sets the quaternion to the given euler angles in degrees.
        Parameters:
        yaw - the rotation around the y axis in degrees
        pitch - the rotation around the x axis in degrees
        roll - the rotation around the z axis degrees
        Returns:
        this quaternion
      • setEulerAnglesRad

        public Quaterniond setEulerAnglesRad​(double yaw,
                                             double pitch,
                                             double roll)
        Sets the quaternion to the given euler angles in radians.
        Parameters:
        yaw - the rotation around the y axis in radians
        pitch - the rotation around the x axis in radians
        roll - the rotation around the z axis in radians
        Returns:
        this quaternion
      • getGimbalPole

        public int getGimbalPole()
        Get the pole of the gimbal lock, if any.
        Returns:
        positive (+1) for north pole, negative (-1) for south pole, zero (0) when no gimbal lock
      • getRollRad

        public double getRollRad()
        Get the roll euler angle in radians, which is the rotation around the z axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the z axis in radians (between -PI and +PI)
      • getRoll

        public double getRoll()
        Get the roll euler angle in degrees, which is the rotation around the z axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the z axis in degrees (between -180 and +180)
      • getPitchRad

        public double getPitchRad()
        Get the pitch euler angle in radians, which is the rotation around the x axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the x axis in radians (between -(PI/2) and +(PI/2))
      • getPitch

        public double getPitch()
        Get the pitch euler angle in degrees, which is the rotation around the x axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the x axis in degrees (between -90 and +90)
      • getYawRad

        public double getYawRad()
        Get the yaw euler angle in radians, which is the rotation around the y axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the y axis in radians (between -PI and +PI)
      • getYaw

        public double getYaw()
        Get the yaw euler angle in degrees, which is the rotation around the y axis. Requires that this quaternion is normalized.
        Returns:
        the rotation around the y axis in degrees (between -180 and +180)
      • len2

        public static final double len2​(double x,
                                        double y,
                                        double z,
                                        double w)
      • len2

        public double len2()
        Returns:
        the length of this quaternion without square root
      • nor

        public Quaterniond nor()
        Normalizes this quaternion to unit length
        Returns:
        the quaternion for chaining
      • conjugate

        public Quaterniond conjugate()
        Conjugate the quaternion.
        Returns:
        This quaternion for chaining
      • transform

        public Vector3d transform​(Vector3d v)
        Transforms the given vector using this quaternion
        Parameters:
        v - Vector to transform
      • inverse

        public Quaterniond inverse()
        Sets the value of this quaternion to the quaternion inverse of itself. Warning: this quaternion will NOT be normalized. Note that if q not normalized, then q*qinverse=(0,0,0,1) whereas q*qconjugate =(0,0,0,Norm(q)*Norm(q))
        Returns:
        Quaternion
      • mul

        public Quaterniond mul​(Quaterniond other)
        Multiplies this quaternion with another one in the form of this = this * other
        Parameters:
        other - Quaterniond to multiply with
        Returns:
        This quaternion for chaining
      • mul

        public Quaterniond mul​(double x,
                               double y,
                               double z,
                               double w)
        Multiplies this quaternion with another one in the form of this = this * other
        Parameters:
        x - the x component of the other quaternion to multiply with
        y - the y component of the other quaternion to multiply with
        z - the z component of the other quaternion to multiply with
        w - the w component of the other quaternion to multiply with
        Returns:
        This quaternion for chaining
      • mulLeft

        public Quaterniond mulLeft​(Quaterniond other)
        Multiplies this quaternion with another one in the form of this = other * this
        Parameters:
        other - Quaterniond to multiply with
        Returns:
        This quaternion for chaining
      • mulLeft

        public Quaterniond mulLeft​(double x,
                                   double y,
                                   double z,
                                   double w)
        Multiplies this quaternion with another one in the form of this = other * this
        Parameters:
        x - the x component of the other quaternion to multiply with
        y - the y component of the other quaternion to multiply with
        z - the z component of the other quaternion to multiply with
        w - the w component of the other quaternion to multiply with
        Returns:
        This quaternion for chaining
      • mulInverse

        public Quaterniond mulInverse​(Quaterniond q1)
        Multiplies this quaternion by the inverse of quaternion q1 and places the value into this quaternion. The value of the argument quaternion is preserved (this = this * q^-1). Warning: this quaternion will NOT be normalized.
        Parameters:
        q1 - the other quaternion
        Returns:
        Quaterniond
      • mulLeftInverse

        public Quaterniond mulLeftInverse​(Quaterniond q1)
        Pre-multiplies this quaternion by the inverse of quaternion q and places the value into this quaternion. The value of the argument quaternion is preserved (this = q^-1 * this). Warning: this quaternion will NOT be normalized.
        Parameters:
        q1 - the other quaternion
        Returns:
        Quaterniond
      • toMatrix

        public void toMatrix​(double[] matrix)
        Fills a 4x4 matrix with the rotation matrix represented by this quaternion.
        Parameters:
        matrix - Matrix to fill
      • idt

        public Quaterniond idt()
        Sets the quaternion to an identity Quaterniond
        Returns:
        this quaternion for chaining
      • isIdentity

        public boolean isIdentity()
        Returns:
        If this quaternion is an identity Quaterniond
      • isIdentity

        public boolean isIdentity​(double tolerance)
        Returns:
        If this quaternion is an identity Quaterniond
      • setFromAxis

        public Quaterniond setFromAxis​(Vector3d axis,
                                       double degrees)
        Sets the quaternion components from the given axis and angle around that axis.
        Parameters:
        axis - The axis
        degrees - The angle in degrees
        Returns:
        This quaternion for chaining.
      • setFromAxisRad

        public Quaterniond setFromAxisRad​(Vector3d axis,
                                          double radians)
        Sets the quaternion components from the given axis and angle around that axis.
        Parameters:
        axis - The axis
        radians - The angle in radians
        Returns:
        This quaternion for chaining.
      • setFromAxis

        public Quaterniond setFromAxis​(double x,
                                       double y,
                                       double z,
                                       double degrees)
        Sets the quaternion components from the given axis and angle around that axis.
        Parameters:
        x - X direction of the axis
        y - Y direction of the axis
        z - Z direction of the axis
        degrees - The angle in degrees
        Returns:
        This quaternion for chaining.
      • setFromAxisRad

        public Quaterniond setFromAxisRad​(double x,
                                          double y,
                                          double z,
                                          double radians)
        Sets the quaternion components from the given axis and angle around that axis.
        Parameters:
        x - X direction of the axis
        y - Y direction of the axis
        z - Z direction of the axis
        radians - The angle in radians
        Returns:
        This quaternion for chaining.
      • setFromMatrix

        public Quaterniond setFromMatrix​(boolean normalizeAxes,
                                         Matrix4d matrix)
        Sets the Quaterniond from the given matrix, optionally removing any scaling.
      • setFromMatrix

        public Quaterniond setFromMatrix​(Matrix4d matrix)
        Sets the Quaterniond from the given rotation matrix, which must not contain scaling.
      • setFromAxes

        public Quaterniond setFromAxes​(double xx,
                                       double xy,
                                       double xz,
                                       double yx,
                                       double yy,
                                       double yz,
                                       double zx,
                                       double zy,
                                       double zz)

        Sets the Quaterniond from the given x-, y- and z-axis which have to be orthonormal.

        Taken from Bones framework for JPCT, see http://www.aptalkarga.com/bones/ which in turn took it from Graphics Gem code at ftp://ftp.cis.upenn.edu/pub/graphics/shoemake/quatut.ps.Z.

        Parameters:
        xx - x-axis x-coordinate
        xy - x-axis y-coordinate
        xz - x-axis z-coordinate
        yx - y-axis x-coordinate
        yy - y-axis y-coordinate
        yz - y-axis z-coordinate
        zx - z-axis x-coordinate
        zy - z-axis y-coordinate
        zz - z-axis z-coordinate
      • setFromAxes

        public Quaterniond setFromAxes​(boolean normalizeAxes,
                                       double xx,
                                       double xy,
                                       double xz,
                                       double yx,
                                       double yy,
                                       double yz,
                                       double zx,
                                       double zy,
                                       double zz)

        Sets the Quaterniond from the given x-, y- and z-axis.

        Taken from Bones framework for JPCT, see http://www.aptalkarga.com/bones/ which in turn took it from Graphics Gem code at ftp://ftp.cis.upenn.edu/pub/graphics/shoemake/quatut.ps.Z.

        Parameters:
        normalizeAxes - whether to normalize the axes (necessary when they contain scaling)
        xx - x-axis x-coordinate
        xy - x-axis y-coordinate
        xz - x-axis z-coordinate
        yx - y-axis x-coordinate
        yy - y-axis y-coordinate
        yz - y-axis z-coordinate
        zx - z-axis x-coordinate
        zy - z-axis y-coordinate
        zz - z-axis z-coordinate
      • setFromCross

        public Quaterniond setFromCross​(Vector3d v1,
                                        Vector3d v2)
        Set this quaternion to the rotation between two vectors.
        Parameters:
        v1 - The base vector, which should be normalized.
        v2 - The target vector, which should be normalized.
        Returns:
        This quaternion for chaining
      • setFromCross

        public Quaterniond setFromCross​(double x1,
                                        double y1,
                                        double z1,
                                        double x2,
                                        double y2,
                                        double z2)
        Set this quaternion to the rotation between two vectors.
        Parameters:
        x1 - The base vectors x value, which should be normalized.
        y1 - The base vectors y value, which should be normalized.
        z1 - The base vectors z value, which should be normalized.
        x2 - The target vector x value, which should be normalized.
        y2 - The target vector y value, which should be normalized.
        z2 - The target vector z value, which should be normalized.
        Returns:
        This quaternion for chaining
      • slerp

        public Quaterniond slerp​(Quaterniond end,
                                 double alpha)
        Spherical linear interpolation between this quaternion and the other quaternion, based on the alpha value in the range [0,1]. Taken from. Taken from Bones framework for JPCT, see http://www.aptalkarga.com/bones/
        Parameters:
        end - the end quaternion
        alpha - alpha in the range [0,1]
        Returns:
        this quaternion for chaining
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object
      • equals

        public boolean equals​(java.lang.Object obj)
        Overrides:
        equals in class java.lang.Object
      • dot

        public static final double dot​(double x1,
                                       double y1,
                                       double z1,
                                       double w1,
                                       double x2,
                                       double y2,
                                       double z2,
                                       double w2)
        Get the dot product between the two quaternions (commutative).
        Parameters:
        x1 - the x component of the first quaternion
        y1 - the y component of the first quaternion
        z1 - the z component of the first quaternion
        w1 - the w component of the first quaternion
        x2 - the x component of the second quaternion
        y2 - the y component of the second quaternion
        z2 - the z component of the second quaternion
        w2 - the w component of the second quaternion
        Returns:
        the dot product between the first and second quaternion.
      • dot

        public double dot​(Quaterniond other)
        Get the dot product between this and the other quaternion (commutative).
        Parameters:
        other - the other quaternion.
        Returns:
        the dot product of this and the other quaternion.
      • dot

        public double dot​(double x,
                          double y,
                          double z,
                          double w)
        Get the dot product between this and the other quaternion (commutative).
        Parameters:
        x - the x component of the other quaternion
        y - the y component of the other quaternion
        z - the z component of the other quaternion
        w - the w component of the other quaternion
        Returns:
        the dot product of this and the other quaternion.
      • mul

        public Quaterniond mul​(double scalar)
        Multiplies the components of this quaternion with the given scalar.
        Parameters:
        scalar - the scalar.
        Returns:
        this quaternion for chaining.
      • mulAdd

        public Quaterniond mulAdd​(Quaterniond q,
                                  double s)
        Add quaternion q, scaled by s, to this quaternion (this = this + q * s)
        Parameters:
        q -
        s -
        Returns:
        this quaternion for chaining.
      • getAxisAngle

        public double getAxisAngle​(Vector3d axis)
        Get the axis angle representation of the rotation in degrees. The supplied vector will receive the axis (x, y and z values) of the rotation and the value returned is the angle in degrees around that axis. Note that this method will alter the supplied vector, the existing value of the vector is ignored.

        This will normalize this quaternion if needed. The received axis is a unit vector. However, if this is an identity quaternion (no rotation), then the length of the axis may be zero.
        Parameters:
        axis - vector which will receive the axis
        Returns:
        the angle in degrees
        See Also:
        wikipedia, calculation
      • getAxisAngleRad

        public double getAxisAngleRad​(Vector3d axis)
        Get the axis-angle representation of the rotation in radians. The supplied vector will receive the axis (x, y and z values) of the rotation and the value returned is the angle in radians around that axis. Note that this method will alter the supplied vector, the existing value of the vector is ignored.

        This will normalize this quaternion if needed. The received axis is a unit vector. However, if this is an identity quaternion (no rotation), then the length of the axis may be zero.
        Parameters:
        axis - vector which will receive the axis
        Returns:
        the angle in radians
        See Also:
        wikipedia, calculation
      • getAngleRad

        public double getAngleRad()
        Get the angle in radians of the rotation this quaternion represents. Does not normalize the quaternion. Use getAxisAngleRad(Vector3d) to get both the axis and the angle of this rotation. Use getAngleAroundRad(Vector3d) to get the angle around a specific axis.
        Returns:
        the angle in radians of the rotation
      • getAngle

        public double getAngle()
        Get the angle in degrees of the rotation this quaternion represents. Use getAxisAngle(Vector3d) to get both the axis and the angle of this rotation. Use getAngleAround(Vector3d) to get the angle around a specific axis.
        Returns:
        the angle in degrees of the rotation
      • getSwingTwist

        public void getSwingTwist​(double axisX,
                                  double axisY,
                                  double axisZ,
                                  Quaterniond swing,
                                  Quaterniond twist)
        Get the swing rotation and twist rotation for the specified axis. The twist rotation represents the rotation around the specified axis. The swing rotation represents the rotation of the specified axis itself, which is the rotation around an axis perpendicular to the specified axis.

        The swing and twist rotation can be used to reconstruct the original quaternion: this = swing * twist
        Parameters:
        axisX - the X component of the normalized axis for which to get the swing and twist rotation
        axisY - the Y component of the normalized axis for which to get the swing and twist rotation
        axisZ - the Z component of the normalized axis for which to get the swing and twist rotation
        swing - will receive the swing rotation: the rotation around an axis perpendicular to the specified axis
        twist - will receive the twist rotation: the rotation around the specified axis
        See Also:
        calculation
      • getSwingTwist

        public void getSwingTwist​(Vector3d axis,
                                  Quaterniond swing,
                                  Quaterniond twist)
        Get the swing rotation and twist rotation for the specified axis. The twist rotation represents the rotation around the specified axis. The swing rotation represents the rotation of the specified axis itself, which is the rotation around an axis perpendicular to the specified axis.

        The swing and twist rotation can be used to reconstruct the original quaternion: this = swing * twist
        Parameters:
        axis - the normalized axis for which to get the swing and twist rotation
        swing - will receive the swing rotation: the rotation around an axis perpendicular to the specified axis
        twist - will receive the twist rotation: the rotation around the specified axis
        See Also:
        calculation
      • getAngleAroundRad

        public double getAngleAroundRad​(double axisX,
                                        double axisY,
                                        double axisZ)
        Get the angle in radians of the rotation around the specified axis. The axis must be normalized.
        Parameters:
        axisX - the x component of the normalized axis for which to get the angle
        axisY - the y component of the normalized axis for which to get the angle
        axisZ - the z component of the normalized axis for which to get the angle
        Returns:
        the angle in radians of the rotation around the specified axis
      • getAngleAroundRad

        public double getAngleAroundRad​(Vector3d axis)
        Get the angle in radians of the rotation around the specified axis. The axis must be normalized.
        Parameters:
        axis - the normalized axis for which to get the angle
        Returns:
        the angle in radians of the rotation around the specified axis
      • getAngleAround

        public double getAngleAround​(double axisX,
                                     double axisY,
                                     double axisZ)
        Get the angle in degrees of the rotation around the specified axis. The axis must be normalized.
        Parameters:
        axisX - the x component of the normalized axis for which to get the angle
        axisY - the y component of the normalized axis for which to get the angle
        axisZ - the z component of the normalized axis for which to get the angle
        Returns:
        the angle in degrees of the rotation around the specified axis
      • getAngleAround

        public double getAngleAround​(Vector3d axis)
        Get the angle in degrees of the rotation around the specified axis. The axis must be normalized.
        Parameters:
        axis - the normalized axis for which to get the angle
        Returns:
        the angle in degrees of the rotation around the specified axis