Struct Quat 

pub struct Quat {
    pub w: f64,
    pub v: Vec3,
}

A unit quaternion representing a 3D rotation.

Fields

w: f64

Scalar part (w).

v: Vec3

Vector part (x, y, z).

Implementations

impl Quat

pub fn new(w: f64, x: f64, y: f64, z: f64) -> Self

Create a new quaternion from scalar and vector parts.

pub fn identity() -> Self

Identity quaternion (no rotation).

pub fn from_axis_angle(axis: &Vec3, angle: f64) -> Self

Create quaternion from axis-angle representation. axis should be a unit vector, angle in radians.

pub fn normalize(&self) -> Self

Normalize this quaternion to unit length.

pub fn mul(&self, other: &Quat) -> Quat

Quaternion multiplication: self * other.

pub fn conjugate(&self) -> Quat

Conjugate of the quaternion (inverse for unit quaternions).

pub fn to_matrix(&self) -> Mat3

Convert quaternion to 3x3 rotation matrix.

pub fn from_matrix(m: &Mat3) -> Quat

Convert rotation matrix to quaternion. Reference: Shepperd’s method (stable for all rotation matrices).

pub fn exp(w: &Vec3) -> Quat

Exponential map: exp(θ u) where θ u is axis-angle representation. Converts axis-angle to quaternion via q = [cos(θ/2), sin(θ/2) * u]. For small angles, uses first-order approximation.

pub fn log(&self) -> Vec3

Logarithmic map: log(q) returns the axis-angle vector θ u such that q = exp(θ u).

Trait Implementations

impl Clone for Quat

fn clone(&self) -> Quat

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Quat

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for Quat