Quaternion operations

Functions
void	c_quaternion_from_array (const double x[4], c_quaternion *q)
	Construct a quaternion from four scalar components.
void	c_quaternion_from_matrix (const double *x, int ldx, c_quaternion *q)
	Construct a quaternion from a rotation matrix.
void	c_quaternion_from_angle_axis (double angle, const double axis[3], c_quaternion *q)
	Construct a quaternion from angle-axis data.
void	c_quaternion_normalize (c_quaternion *q)
	Normalize a quaternion in place.
void	c_quaternion_add (const c_quaternion *x, const c_quaternion *y, c_quaternion *q)
	Add two quaternions.
void	c_quaternion_subtract (const c_quaternion *x, const c_quaternion *y, c_quaternion *q)
	Subtract two quaternions.
void	c_quaternion_multiply (const c_quaternion *x, const c_quaternion *y, c_quaternion *q)
	Multiply two quaternions.
void	c_quaternion_divide (const c_quaternion *x, const c_quaternion *y, c_quaternion *q)
	Divide two quaternions.
void	c_quaternion_scale (double x, const c_quaternion *y, c_quaternion *q)
	Scale a quaternion.
void	c_quaternion_conjugate (const c_quaternion *q, c_quaternion *qc)
	Compute a quaternion conjugate.
void	c_quaternion_rotate (const c_quaternion *q, const double r[3], double rp[3])
	Rotate a vector using a quaternion.
double	c_quaternion_abs (const c_quaternion *q)
	Compute the quaternion norm.
void	c_quaternion_inverse (const c_quaternion *q, c_quaternion *qinv)
	Compute a quaternion inverse.
void	c_quaternion_to_matrix (const c_quaternion *q, double *r, int ldr)
	Convert a quaternion to a rotation matrix.
void	c_quaternion_to_angle_axis (const c_quaternion *q, double *angle, double axis[3])
	Convert a quaternion to angle-axis data.
void	c_quaternion_exp (const c_quaternion *q, c_quaternion *rst)
	Compute the quaternion exponential.
void	c_quaternion_log (const c_quaternion *q, c_quaternion *rst)
	Compute the quaternion logarithm.
void	c_quaternion_pow (const c_quaternion *q, double exponent, c_quaternion *rst)
	Raise a quaternion to a real power.
double	c_quaternion_dot_product (const c_quaternion *x, const c_quaternion *y)
	Compute the quaternion dot product.
void	c_quaternion_to_roll_pitch_yaw (const c_quaternion *q, double *roll, double *pitch, double *yaw)
	Convert a quaternion to roll, pitch, and yaw angles.

Detailed Description

Function Documentation

c_quaternion_from_array()

void c_quaternion_from_array	(	const double	x[4],
		c_quaternion *	q
	)

Construct a quaternion from four scalar components.

Parameters

x	Four components in w,x,y,z order.
q	Output quaternion.

c_quaternion_from_matrix()

void c_quaternion_from_matrix	(	const double *	x,
		int	ldx,
		c_quaternion *	q
	)

Construct a quaternion from a rotation matrix.

Parameters

x	Rotation matrix.
ldx	Leading dimension of x.
q	Output quaternion.

c_quaternion_from_angle_axis()

void c_quaternion_from_angle_axis	(	double	angle,
		const double	axis[3],
		c_quaternion *	q
	)

Construct a quaternion from angle-axis data.

Parameters

angle	Rotation angle in radians.
axis	Unit rotation axis.
q	Output quaternion.

c_quaternion_normalize()

void c_quaternion_normalize

(

c_quaternion *

q

)

Normalize a quaternion in place.

Parameters

q	Quaternion updated in place.

c_quaternion_add()

void c_quaternion_add	(	const c_quaternion *	x,
		const c_quaternion *	y,
		c_quaternion *	q
	)

Add two quaternions.

Parameters

x	First quaternion.
y	Second quaternion.
q	Output quaternion.

c_quaternion_subtract()

void c_quaternion_subtract	(	const c_quaternion *	x,
		const c_quaternion *	y,
		c_quaternion *	q
	)

Subtract two quaternions.

Parameters

x	First quaternion.
y	Second quaternion.
q	Output quaternion.

c_quaternion_multiply()

void c_quaternion_multiply	(	const c_quaternion *	x,
		const c_quaternion *	y,
		c_quaternion *	q
	)

Multiply two quaternions.

Parameters

x	First quaternion.
y	Second quaternion.
q	Output quaternion.

c_quaternion_divide()

void c_quaternion_divide	(	const c_quaternion *	x,
		const c_quaternion *	y,
		c_quaternion *	q
	)

Divide two quaternions.

Parameters

x	Numerator quaternion.
y	Denominator quaternion.
q	Output quaternion.

c_quaternion_scale()

void c_quaternion_scale	(	double	x,
		const c_quaternion *	y,
		c_quaternion *	q
	)

Scale a quaternion.

Parameters

x	Scale factor.
y	Input quaternion.
q	Output quaternion.

c_quaternion_conjugate()

void c_quaternion_conjugate	(	const c_quaternion *	q,
		c_quaternion *	qc
	)

Compute a quaternion conjugate.

Parameters

q	Input quaternion.
qc	Output conjugate.

c_quaternion_rotate()

void c_quaternion_rotate	(	const c_quaternion *	q,
		const double	r[3],
		double	rp[3]
	)

Rotate a vector using a quaternion.

Parameters

q	Rotation quaternion.
r	Input vector.
rp	Output rotated vector.

c_quaternion_abs()

double c_quaternion_abs

(

const c_quaternion *

q

)

Compute the quaternion norm.

Parameters

q	Quaternion.

Returns

Quaternion magnitude.

c_quaternion_inverse()

void c_quaternion_inverse	(	const c_quaternion *	q,
		c_quaternion *	qinv
	)

Compute a quaternion inverse.

Parameters

q	Input quaternion.
qinv	Output inverse.

c_quaternion_to_matrix()

void c_quaternion_to_matrix	(	const c_quaternion *	q,
		double *	r,
		int	ldr
	)

Convert a quaternion to a rotation matrix.

Parameters

q	Quaternion.
r	Output matrix.
ldr	Leading dimension of r.

c_quaternion_to_angle_axis()

void c_quaternion_to_angle_axis	(	const c_quaternion *	q,
		double *	angle,
		double	axis[3]
	)

Convert a quaternion to angle-axis data.

Parameters

q	Quaternion.
angle	Output angle.
axis	Output axis.

c_quaternion_exp()

void c_quaternion_exp	(	const c_quaternion *	q,
		c_quaternion *	rst
	)

Compute the quaternion exponential.

Parameters

q	Input quaternion.
rst	Output quaternion.

c_quaternion_log()

void c_quaternion_log	(	const c_quaternion *	q,
		c_quaternion *	rst
	)

Compute the quaternion logarithm.

Parameters

q	Input quaternion.
rst	Output quaternion.

c_quaternion_pow()

void c_quaternion_pow	(	const c_quaternion *	q,
		double	exponent,
		c_quaternion *	rst
	)

Raise a quaternion to a real power.

Parameters

q	Input quaternion.
exponent	Power.
rst	Output quaternion.

c_quaternion_dot_product()

double c_quaternion_dot_product	(	const c_quaternion *	x,
		const c_quaternion *	y
	)

Compute the quaternion dot product.

Parameters

x	First quaternion.
y	Second quaternion.

Returns

Dot product.

c_quaternion_to_roll_pitch_yaw()

void c_quaternion_to_roll_pitch_yaw	(	const c_quaternion *	q,
		double *	roll,
		double *	pitch,
		double *	yaw
	)

Convert a quaternion to roll, pitch, and yaw angles.

Parameters

q	Quaternion.
roll	Output roll.
pitch	Output pitch.
yaw	Output yaw.