#include "shz_vector.h"
#include "shz_mem.h"
#include "inline/shz_quat.inl.h"

Include dependency graph for shz_quat.h:

This graph shows which files directly or indirectly include this file:

Data Structures
struct	shz_quat_t

Macros
#define	SHZ_QUAT_SLERP_PHI_EPSILON

Typedefs
typedef shz_quat_t	shz_quat

Functions
shz_vec3_t	shz_quat_transform_vec3 (shz_quat_t q, shz_vec3_t v) SHZ_NOEXCEPT

Initialization
Routines for creating and initializing quaternions.
shz_quat_t	shz_quat_init (float w, float x, float y, float z) SHZ_NOEXCEPT

shz_quat_t	shz_quat_identity (void) SHZ_NOEXCEPT

bool	shz_quat_equal (shz_quat_t a, shz_quat_t b) SHZ_NOEXCEPT

shz_quat_t	shz_quat_from_angles_xyz (float xangle, float yangle, float zangle) SHZ_NOEXCEPT

shz_quat_t	shz_quat_from_axis_angle (shz_vec3_t axis, float angle) SHZ_NOEXCEPT

shz_quat_t	shz_quat_from_look_axis (shz_vec3_t forward, shz_vec3_t up) SHZ_NOEXCEPT

shz_quat_t	shz_quat_from_rotated_axis (shz_vec3_t v1, shz_vec3_t v2) SHZ_NOEXCEPT

shz_quat_t	shz_quat_lerp (shz_quat_t a, shz_quat_t b, float t) SHZ_NOEXCEPT

shz_quat_t	shz_quat_nlerp (shz_quat_t a, shz_quat_t b, float t) SHZ_NOEXCEPT

shz_quat_t	shz_quat_slerp (shz_quat_t q, shz_quat_t p, float t) SHZ_NOEXCEPT

Properties
Routines returning derived values from a quaternion.
float	shz_quat_angle (shz_quat_t q) SHZ_NOEXCEPT

shz_vec3_t	shz_quat_axis (shz_quat_t q) SHZ_NOEXCEPT

float	shz_quat_angle_x (shz_quat_t q) SHZ_NOEXCEPT

float	shz_quat_angle_y (shz_quat_t q) SHZ_NOEXCEPT

float	shz_quat_angle_z (shz_quat_t q) SHZ_NOEXCEPT

void	shz_quat_to_axis_angle (shz_quat_t q, shz_vec3_t vec, float angle) SHZ_NOEXCEPT

shz_vec3_t	shz_quat_to_angles_xyz (shz_quat_t q) SHZ_NOEXCEPT

float	shz_quat_magnitude_sqr (shz_quat_t quat) SHZ_NOEXCEPT

float	shz_quat_magnitude (shz_quat_t quat) SHZ_NOEXCEPT

float	shz_quat_magnitude_inv (shz_quat_t quat) SHZ_NOEXCEPT

Modifiers
Routines for returning new quaternions derived from existing ones.
shz_quat_t	shz_quat_normalize (shz_quat_t quat) SHZ_NOEXCEPT

shz_quat_t	shz_quat_normalize_safe (shz_quat_t quat) SHZ_NOEXCEPT

shz_quat_t	shz_quat_conjugate (shz_quat_t quat) SHZ_NOEXCEPT

shz_quat_t	shz_quat_inv (shz_quat_t quat) SHZ_NOEXCEPT

Arithmetic
Routines performing calculations with quaternions.
shz_quat_t	shz_quat_add (shz_quat_t q, shz_quat_t p) SHZ_NOEXCEPT

shz_quat_t	shz_quat_scale (shz_quat_t q, float f) SHZ_NOEXCEPT

shz_quat_t	shz_quat_mult (shz_quat_t q1, shz_quat_t q2) SHZ_NOEXCEPT

float	shz_quat_dot (shz_quat_t q1, shz_quat_t q2) SHZ_NOEXCEPT

shz_vec2_t	shz_quat_dot2 (shz_quat_t l, shz_quat_t r1, shz_quat_t r2) SHZ_NOEXCEPT

shz_vec3_t	shz_quat_dot3 (shz_quat_t l, shz_quat_t r1, shz_quat_t r2, shz_quat_t r3) SHZ_NOEXCEPT

Detailed Description

Routines for operating upon quaternions.

This file contains the public type(s) and interface providing the quaternion math API.

Todo

shz_quat_rotate_towards()
shz_quat_to_angles_xyz()
shz_quat_angle_between()

Author: 2025, 2026 Falco Girgis; 2025 Oleg Endo

Copyright: MIT License

Definition in file shz_quat.h.

Macro Definition Documentation

◆ SHZ_QUAT_SLERP_PHI_EPSILON

#define SHZ_QUAT_SLERP_PHI_EPSILON

Minimum epsilon below which shz_quat_slerp() performs no interpolation.

Definition at line 30 of file shz_quat.h.

Typedef Documentation

◆ shz_quat

typedef shz_quat_t shz_quat

Alternate shz_quat_t C typedef for those who hate POSIX style.

Definition at line 57 of file shz_quat.h.

Function Documentation

◆ shz_quat_init()

shz_quat_t shz_quat_init	(	float	w,
		float	x,
		float	y,
		float	z )

Initializes and returns a new quaternion with the given components, in WXYZ order.

◆ shz_quat_identity()

shz_quat_t shz_quat_identity ( void )

Initializes and returns an identity quaternion.

◆ shz_quat_equal()

bool shz_quat_equal	(	shz_quat_t	a,
		shz_quat_t	b )

Returns true if the two given quaternions are considered equal based on either absolute or relative tolerance.

◆ shz_quat_from_angles_xyz()

shz_quat_t shz_quat_from_angles_xyz	(	float	xangle,
		float	yangle,
		float	zangle )

Initializes and returns a quaternion with the given X-Y-Z rotations in radians.

The rotation is applied first around the X-axis, then the Y-, then the Z-axis.

Note: These angles are Tait-Bryan angles representing an intrinsic rotation.

◆ shz_quat_from_axis_angle()

shz_quat_t shz_quat_from_axis_angle	(	shz_vec3_t	axis,
		float	angle )

Initializes and returns a quaternion representing a rotation of angle radians about the given axis.

◆ shz_quat_from_look_axis()

shz_quat_t shz_quat_from_look_axis	(	shz_vec3_t	forward,
		shz_vec3_t	up )

Creates a quaternion looking in the given direction with the given reference direction.

◆ shz_quat_from_rotated_axis()

shz_quat_t shz_quat_from_rotated_axis	(	shz_vec3_t	v1,
		shz_vec3_t	v2 )

Returns the quaternion representing the rotation from axis v1 to v2.

◆ shz_quat_lerp()

shz_quat_t shz_quat_lerp	(	shz_quat_t	a,
		shz_quat_t	b,
		float	t )

Returns the quaternion that is linearly interpolating a to b, by a t factor of 0.0f-1.0f.

◆ shz_quat_nlerp()

shz_quat_t shz_quat_nlerp	(	shz_quat_t	a,
		shz_quat_t	b,
		float	t )

Equivalent to shz_quat_lerp(), except that the resulting quaternion is normalized.

◆ shz_quat_slerp()

shz_quat_t shz_quat_slerp	(	shz_quat_t	q,
		shz_quat_t	p,
		float	t )

Returns the quaternion that is spherically linearly interpolating a to b, by a t factor of 0.0f-1.0f.

Warning: The returned quaternion is not guaranteed to be normalized due to a floating-point error. Callers should normalize the result before reuse, especially when performing repeated interpolations.

◆ shz_quat_angle()

float shz_quat_angle ( shz_quat_t q )

Returns the angle of rotation from the given quaternion.

◆ shz_quat_axis()

shz_vec3_t shz_quat_axis ( shz_quat_t q )

Returns the axis of rotation from the given quaternion.

◆ shz_quat_to_axis_angle()

void shz_quat_to_axis_angle	(	shz_quat_t	q,
		shz_vec3_t *	vec,
		float *	angle )

Returns both the axis and angle of rotation simultaneously (faster if both are needed) from the given quaternion.

◆ shz_quat_to_angles_xyz()

shz_vec3_t shz_quat_to_angles_xyz ( shz_quat_t q )

Returns the roll, pitch, and yaw angles of rotation represented by the given quaternion.

◆ shz_quat_magnitude_sqr()

float shz_quat_magnitude_sqr ( shz_quat_t quat )

Returns the squared magnitude of the given quaternion.

◆ shz_quat_magnitude()

float shz_quat_magnitude ( shz_quat_t quat )

Returns the magnitude of the given quaternion.

◆ shz_quat_magnitude_inv()

float shz_quat_magnitude_inv ( shz_quat_t quat )

Returns the inverse magnitude of the given quaternion.

◆ shz_quat_normalize()

shz_quat_t shz_quat_normalize ( shz_quat_t quat )

Returns the normalized form of the given quaternion.

◆ shz_quat_normalize_safe()

shz_quat_t shz_quat_normalize_safe ( shz_quat_t quat )

SAFELY returns the normalized form of the given quaternion.

Returns the identity quaternion when magnitude is 0.0f.

◆ shz_quat_conjugate()

shz_quat_t shz_quat_conjugate ( shz_quat_t quat )

Returns the conjugate of the given quaternion.

◆ shz_quat_inv()

shz_quat_t shz_quat_inv ( shz_quat_t quat )

Returns the inverse of the given quaternion.

◆ shz_quat_add()

shz_quat_t shz_quat_add	(	shz_quat_t	q,
		shz_quat_t	p )

Returns the quaternion produced from adding each component of the given quaternions.

◆ shz_quat_scale()

shz_quat_t shz_quat_scale	(	shz_quat_t	q,
		float	f )

Scales the components of the given quaternion by the given factor.

◆ shz_quat_mult()

shz_quat_t shz_quat_mult	(	shz_quat_t	q1,
		shz_quat_t	q2 )

Multiplies the two quaternions, returning the result as a new quaternion.

◆ shz_quat_dot()

float shz_quat_dot	(	shz_quat_t	q1,
		shz_quat_t	q2 )

Returns the dot product of the two quaternions.

◆ shz_quat_dot2()

shz_vec2_t shz_quat_dot2	(	shz_quat_t	l,
		shz_quat_t	r1,
		shz_quat_t	r2 )

Returns the two dot products taken between the l quaternion and the r1 and r2 quaternions.

◆ shz_quat_dot3()

shz_vec3_t shz_quat_dot3	(	shz_quat_t	l,
		shz_quat_t	r1,
		shz_quat_t	r2,
		shz_quat_t	r3 )

Returns the two dot products taken between the l quaternion and the r1, r2, and r3 quaternions.

◆ shz_quat_transform_vec3()

shz_vec3_t shz_quat_transform_vec3	(	shz_quat_t	q,
		shz_vec3_t	v )

Rotates a vector by the given quaternion.

Note: This routine is meant for one-off rotations of a single vector by a single quaternion. If you plan to rotate multiple vectors by the same quaternion, you should use the XMTRX API to apply the quaternion as a rotation matrix.

See also: shz_xmtrx_apply_rotation_quat()

Data Structures

Macros

Typedefs

Functions