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// Generated from quat.rs.tera template. Edit the template, not the generated file.
use crate::{
euler::{EulerFromQuaternion, EulerRot, EulerToQuaternion},
f64::math,
DMat3, DMat4, DVec2, DVec3, DVec4, Quat,
};
#[cfg(not(target_arch = "spirv"))]
use core::fmt;
use core::iter::{Product, Sum};
use core::ops::{Add, Div, Mul, MulAssign, Neg, Sub};
/// Creates a quaternion from `x`, `y`, `z` and `w` values.
///
/// This should generally not be called manually unless you know what you are doing. Use
/// one of the other constructors instead such as `identity` or `from_axis_angle`.
#[inline]
#[must_use]
pub const fn dquat(x: f64, y: f64, z: f64, w: f64) -> DQuat {
DQuat::from_xyzw(x, y, z, w)
}
/// A quaternion representing an orientation.
///
/// This quaternion is intended to be of unit length but may denormalize due to
/// floating point "error creep" which can occur when successive quaternion
/// operations are applied.
#[derive(Clone, Copy)]
#[cfg_attr(not(target_arch = "spirv"), repr(C))]
#[cfg_attr(target_arch = "spirv", repr(simd))]
pub struct DQuat {
pub x: f64,
pub y: f64,
pub z: f64,
pub w: f64,
}
impl DQuat {
/// All zeros.
const ZERO: Self = Self::from_array([0.0; 4]);
/// The identity quaternion. Corresponds to no rotation.
pub const IDENTITY: Self = Self::from_xyzw(0.0, 0.0, 0.0, 1.0);
/// All NANs.
pub const NAN: Self = Self::from_array([f64::NAN; 4]);
/// Creates a new rotation quaternion.
///
/// This should generally not be called manually unless you know what you are doing.
/// Use one of the other constructors instead such as `identity` or `from_axis_angle`.
///
/// `from_xyzw` is mostly used by unit tests and `serde` deserialization.
///
/// # Preconditions
///
/// This function does not check if the input is normalized, it is up to the user to
/// provide normalized input or to normalized the resulting quaternion.
#[inline(always)]
#[must_use]
pub const fn from_xyzw(x: f64, y: f64, z: f64, w: f64) -> Self {
Self { x, y, z, w }
}
/// Creates a rotation quaternion from an array.
///
/// # Preconditions
///
/// This function does not check if the input is normalized, it is up to the user to
/// provide normalized input or to normalized the resulting quaternion.
#[inline]
#[must_use]
pub const fn from_array(a: [f64; 4]) -> Self {
Self::from_xyzw(a[0], a[1], a[2], a[3])
}
/// Creates a new rotation quaternion from a 4D vector.
///
/// # Preconditions
///
/// This function does not check if the input is normalized, it is up to the user to
/// provide normalized input or to normalized the resulting quaternion.
#[inline]
#[must_use]
pub const fn from_vec4(v: DVec4) -> Self {
Self {
x: v.x,
y: v.y,
z: v.z,
w: v.w,
}
}
/// Creates a rotation quaternion from a slice.
///
/// # Preconditions
///
/// This function does not check if the input is normalized, it is up to the user to
/// provide normalized input or to normalized the resulting quaternion.
///
/// # Panics
///
/// Panics if `slice` length is less than 4.
#[inline]
#[must_use]
pub fn from_slice(slice: &[f64]) -> Self {
Self::from_xyzw(slice[0], slice[1], slice[2], slice[3])
}
/// Writes the quaternion to an unaligned slice.
///
/// # Panics
///
/// Panics if `slice` length is less than 4.
#[inline]
pub fn write_to_slice(self, slice: &mut [f64]) {
slice[0] = self.x;
slice[1] = self.y;
slice[2] = self.z;
slice[3] = self.w;
}
/// Create a quaternion for a normalized rotation `axis` and `angle` (in radians).
///
/// The axis must be a unit vector.
///
/// # Panics
///
/// Will panic if `axis` is not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn from_axis_angle(axis: DVec3, angle: f64) -> Self {
glam_assert!(axis.is_normalized());
let (s, c) = math::sin_cos(angle * 0.5);
let v = axis * s;
Self::from_xyzw(v.x, v.y, v.z, c)
}
/// Create a quaternion that rotates `v.length()` radians around `v.normalize()`.
///
/// `from_scaled_axis(Vec3::ZERO)` results in the identity quaternion.
#[inline]
#[must_use]
pub fn from_scaled_axis(v: DVec3) -> Self {
let length = v.length();
if length == 0.0 {
Self::IDENTITY
} else {
Self::from_axis_angle(v / length, length)
}
}
/// Creates a quaternion from the `angle` (in radians) around the x axis.
#[inline]
#[must_use]
pub fn from_rotation_x(angle: f64) -> Self {
let (s, c) = math::sin_cos(angle * 0.5);
Self::from_xyzw(s, 0.0, 0.0, c)
}
/// Creates a quaternion from the `angle` (in radians) around the y axis.
#[inline]
#[must_use]
pub fn from_rotation_y(angle: f64) -> Self {
let (s, c) = math::sin_cos(angle * 0.5);
Self::from_xyzw(0.0, s, 0.0, c)
}
/// Creates a quaternion from the `angle` (in radians) around the z axis.
#[inline]
#[must_use]
pub fn from_rotation_z(angle: f64) -> Self {
let (s, c) = math::sin_cos(angle * 0.5);
Self::from_xyzw(0.0, 0.0, s, c)
}
/// Creates a quaternion from the given Euler rotation sequence and the angles (in radians).
#[inline]
#[must_use]
pub fn from_euler(euler: EulerRot, a: f64, b: f64, c: f64) -> Self {
euler.new_quat(a, b, c)
}
/// From the columns of a 3x3 rotation matrix.
#[inline]
#[must_use]
pub(crate) fn from_rotation_axes(x_axis: DVec3, y_axis: DVec3, z_axis: DVec3) -> Self {
// Based on https://github.com/microsoft/DirectXMath `XM$quaternionRotationMatrix`
let (m00, m01, m02) = x_axis.into();
let (m10, m11, m12) = y_axis.into();
let (m20, m21, m22) = z_axis.into();
if m22 <= 0.0 {
// x^2 + y^2 >= z^2 + w^2
let dif10 = m11 - m00;
let omm22 = 1.0 - m22;
if dif10 <= 0.0 {
// x^2 >= y^2
let four_xsq = omm22 - dif10;
let inv4x = 0.5 / math::sqrt(four_xsq);
Self::from_xyzw(
four_xsq * inv4x,
(m01 + m10) * inv4x,
(m02 + m20) * inv4x,
(m12 - m21) * inv4x,
)
} else {
// y^2 >= x^2
let four_ysq = omm22 + dif10;
let inv4y = 0.5 / math::sqrt(four_ysq);
Self::from_xyzw(
(m01 + m10) * inv4y,
four_ysq * inv4y,
(m12 + m21) * inv4y,
(m20 - m02) * inv4y,
)
}
} else {
// z^2 + w^2 >= x^2 + y^2
let sum10 = m11 + m00;
let opm22 = 1.0 + m22;
if sum10 <= 0.0 {
// z^2 >= w^2
let four_zsq = opm22 - sum10;
let inv4z = 0.5 / math::sqrt(four_zsq);
Self::from_xyzw(
(m02 + m20) * inv4z,
(m12 + m21) * inv4z,
four_zsq * inv4z,
(m01 - m10) * inv4z,
)
} else {
// w^2 >= z^2
let four_wsq = opm22 + sum10;
let inv4w = 0.5 / math::sqrt(four_wsq);
Self::from_xyzw(
(m12 - m21) * inv4w,
(m20 - m02) * inv4w,
(m01 - m10) * inv4w,
four_wsq * inv4w,
)
}
}
}
/// Creates a quaternion from a 3x3 rotation matrix.
#[inline]
#[must_use]
pub fn from_mat3(mat: &DMat3) -> Self {
Self::from_rotation_axes(mat.x_axis, mat.y_axis, mat.z_axis)
}
/// Creates a quaternion from a 3x3 rotation matrix inside a homogeneous 4x4 matrix.
#[inline]
#[must_use]
pub fn from_mat4(mat: &DMat4) -> Self {
Self::from_rotation_axes(
mat.x_axis.truncate(),
mat.y_axis.truncate(),
mat.z_axis.truncate(),
)
}
/// Gets the minimal rotation for transforming `from` to `to`. The rotation is in the
/// plane spanned by the two vectors. Will rotate at most 180 degrees.
///
/// The inputs must be unit vectors.
///
/// `from_rotation_arc(from, to) * from ≈ to`.
///
/// For near-singular cases (from≈to and from≈-to) the current implementation
/// is only accurate to about 0.001 (for `f32`).
///
/// # Panics
///
/// Will panic if `from` or `to` are not normalized when `glam_assert` is enabled.
#[must_use]
pub fn from_rotation_arc(from: DVec3, to: DVec3) -> Self {
glam_assert!(from.is_normalized());
glam_assert!(to.is_normalized());
const ONE_MINUS_EPS: f64 = 1.0 - 2.0 * f64::EPSILON;
let dot = from.dot(to);
if dot > ONE_MINUS_EPS {
// 0° singularity: from ≈ to
Self::IDENTITY
} else if dot < -ONE_MINUS_EPS {
// 180° singularity: from ≈ -to
use core::f64::consts::PI; // half a turn = 𝛕/2 = 180°
Self::from_axis_angle(from.any_orthonormal_vector(), PI)
} else {
let c = from.cross(to);
Self::from_xyzw(c.x, c.y, c.z, 1.0 + dot).normalize()
}
}
/// Gets the minimal rotation for transforming `from` to either `to` or `-to`. This means
/// that the resulting quaternion will rotate `from` so that it is colinear with `to`.
///
/// The rotation is in the plane spanned by the two vectors. Will rotate at most 90
/// degrees.
///
/// The inputs must be unit vectors.
///
/// `to.dot(from_rotation_arc_colinear(from, to) * from).abs() ≈ 1`.
///
/// # Panics
///
/// Will panic if `from` or `to` are not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn from_rotation_arc_colinear(from: DVec3, to: DVec3) -> Self {
if from.dot(to) < 0.0 {
Self::from_rotation_arc(from, -to)
} else {
Self::from_rotation_arc(from, to)
}
}
/// Gets the minimal rotation for transforming `from` to `to`. The resulting rotation is
/// around the z axis. Will rotate at most 180 degrees.
///
/// The inputs must be unit vectors.
///
/// `from_rotation_arc_2d(from, to) * from ≈ to`.
///
/// For near-singular cases (from≈to and from≈-to) the current implementation
/// is only accurate to about 0.001 (for `f32`).
///
/// # Panics
///
/// Will panic if `from` or `to` are not normalized when `glam_assert` is enabled.
#[must_use]
pub fn from_rotation_arc_2d(from: DVec2, to: DVec2) -> Self {
glam_assert!(from.is_normalized());
glam_assert!(to.is_normalized());
const ONE_MINUS_EPSILON: f64 = 1.0 - 2.0 * f64::EPSILON;
let dot = from.dot(to);
if dot > ONE_MINUS_EPSILON {
// 0° singularity: from ≈ to
Self::IDENTITY
} else if dot < -ONE_MINUS_EPSILON {
// 180° singularity: from ≈ -to
const COS_FRAC_PI_2: f64 = 0.0;
const SIN_FRAC_PI_2: f64 = 1.0;
// rotation around z by PI radians
Self::from_xyzw(0.0, 0.0, SIN_FRAC_PI_2, COS_FRAC_PI_2)
} else {
// vector3 cross where z=0
let z = from.x * to.y - to.x * from.y;
let w = 1.0 + dot;
// calculate length with x=0 and y=0 to normalize
let len_rcp = 1.0 / math::sqrt(z * z + w * w);
Self::from_xyzw(0.0, 0.0, z * len_rcp, w * len_rcp)
}
}
/// Returns the rotation axis (normalized) and angle (in radians) of `self`.
#[inline]
#[must_use]
pub fn to_axis_angle(self) -> (DVec3, f64) {
const EPSILON: f64 = 1.0e-8;
let v = DVec3::new(self.x, self.y, self.z);
let length = v.length();
if length >= EPSILON {
let angle = 2.0 * math::atan2(length, self.w);
let axis = v / length;
(axis, angle)
} else {
(DVec3::X, 0.0)
}
}
/// Returns the rotation axis scaled by the rotation in radians.
#[inline]
#[must_use]
pub fn to_scaled_axis(self) -> DVec3 {
let (axis, angle) = self.to_axis_angle();
axis * angle
}
/// Returns the rotation angles for the given euler rotation sequence.
#[inline]
#[must_use]
pub fn to_euler(self, euler: EulerRot) -> (f64, f64, f64) {
euler.convert_quat(self)
}
/// `[x, y, z, w]`
#[inline]
#[must_use]
pub fn to_array(&self) -> [f64; 4] {
[self.x, self.y, self.z, self.w]
}
/// Returns the vector part of the quaternion.
#[inline]
#[must_use]
pub fn xyz(self) -> DVec3 {
DVec3::new(self.x, self.y, self.z)
}
/// Returns the quaternion conjugate of `self`. For a unit quaternion the
/// conjugate is also the inverse.
#[inline]
#[must_use]
pub fn conjugate(self) -> Self {
Self {
x: -self.x,
y: -self.y,
z: -self.z,
w: self.w,
}
}
/// Returns the inverse of a normalized quaternion.
///
/// Typically quaternion inverse returns the conjugate of a normalized quaternion.
/// Because `self` is assumed to already be unit length this method *does not* normalize
/// before returning the conjugate.
///
/// # Panics
///
/// Will panic if `self` is not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn inverse(self) -> Self {
glam_assert!(self.is_normalized());
self.conjugate()
}
/// Computes the dot product of `self` and `rhs`. The dot product is
/// equal to the cosine of the angle between two quaternion rotations.
#[inline]
#[must_use]
pub fn dot(self, rhs: Self) -> f64 {
DVec4::from(self).dot(DVec4::from(rhs))
}
/// Computes the length of `self`.
#[doc(alias = "magnitude")]
#[inline]
#[must_use]
pub fn length(self) -> f64 {
DVec4::from(self).length()
}
/// Computes the squared length of `self`.
///
/// This is generally faster than `length()` as it avoids a square
/// root operation.
#[doc(alias = "magnitude2")]
#[inline]
#[must_use]
pub fn length_squared(self) -> f64 {
DVec4::from(self).length_squared()
}
/// Computes `1.0 / length()`.
///
/// For valid results, `self` must _not_ be of length zero.
#[inline]
#[must_use]
pub fn length_recip(self) -> f64 {
DVec4::from(self).length_recip()
}
/// Returns `self` normalized to length 1.0.
///
/// For valid results, `self` must _not_ be of length zero.
///
/// Panics
///
/// Will panic if `self` is zero length when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn normalize(self) -> Self {
Self::from_vec4(DVec4::from(self).normalize())
}
/// Returns `true` if, and only if, all elements are finite.
/// If any element is either `NaN`, positive or negative infinity, this will return `false`.
#[inline]
#[must_use]
pub fn is_finite(self) -> bool {
DVec4::from(self).is_finite()
}
#[inline]
#[must_use]
pub fn is_nan(self) -> bool {
DVec4::from(self).is_nan()
}
/// Returns whether `self` of length `1.0` or not.
///
/// Uses a precision threshold of `1e-6`.
#[inline]
#[must_use]
pub fn is_normalized(self) -> bool {
DVec4::from(self).is_normalized()
}
#[inline]
#[must_use]
pub fn is_near_identity(self) -> bool {
// Based on https://github.com/nfrechette/rtm `rtm::quat_near_identity`
let threshold_angle = 0.002_847_144_6;
// Because of floating point precision, we cannot represent very small rotations.
// The closest f32 to 1.0 that is not 1.0 itself yields:
// 0.99999994.acos() * 2.0 = 0.000690533954 rad
//
// An error threshold of 1.e-6 is used by default.
// (1.0 - 1.e-6).acos() * 2.0 = 0.00284714461 rad
// (1.0 - 1.e-7).acos() * 2.0 = 0.00097656250 rad
//
// We don't really care about the angle value itself, only if it's close to 0.
// This will happen whenever quat.w is close to 1.0.
// If the quat.w is close to -1.0, the angle will be near 2*PI which is close to
// a negative 0 rotation. By forcing quat.w to be positive, we'll end up with
// the shortest path.
let positive_w_angle = math::acos_approx(math::abs(self.w)) * 2.0;
positive_w_angle < threshold_angle
}
/// Returns the angle (in radians) for the minimal rotation
/// for transforming this quaternion into another.
///
/// Both quaternions must be normalized.
///
/// # Panics
///
/// Will panic if `self` or `rhs` are not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn angle_between(self, rhs: Self) -> f64 {
glam_assert!(self.is_normalized() && rhs.is_normalized());
math::acos_approx(math::abs(self.dot(rhs))) * 2.0
}
/// Rotates towards `rhs` up to `max_angle` (in radians).
///
/// When `max_angle` is `0.0`, the result will be equal to `self`. When `max_angle` is equal to
/// `self.angle_between(rhs)`, the result will be equal to `rhs`. If `max_angle` is negative,
/// rotates towards the exact opposite of `rhs`. Will not go past the target.
///
/// Both quaternions must be normalized.
///
/// # Panics
///
/// Will panic if `self` or `rhs` are not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn rotate_towards(&self, rhs: Self, max_angle: f64) -> Self {
glam_assert!(self.is_normalized() && rhs.is_normalized());
let angle = self.angle_between(rhs);
if angle <= 1e-4 {
return *self;
}
let s = (max_angle / angle).clamp(-1.0, 1.0);
self.slerp(rhs, s)
}
/// Returns true if the absolute difference of all elements between `self` and `rhs`
/// is less than or equal to `max_abs_diff`.
///
/// This can be used to compare if two quaternions contain similar elements. It works
/// best when comparing with a known value. The `max_abs_diff` that should be used used
/// depends on the values being compared against.
///
/// For more see
/// [comparing floating point numbers](https://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/).
#[inline]
#[must_use]
pub fn abs_diff_eq(self, rhs: Self, max_abs_diff: f64) -> bool {
DVec4::from(self).abs_diff_eq(DVec4::from(rhs), max_abs_diff)
}
/// Performs a linear interpolation between `self` and `rhs` based on
/// the value `s`.
///
/// When `s` is `0.0`, the result will be equal to `self`. When `s`
/// is `1.0`, the result will be equal to `rhs`.
///
/// # Panics
///
/// Will panic if `self` or `end` are not normalized when `glam_assert` is enabled.
#[doc(alias = "mix")]
#[inline]
#[must_use]
pub fn lerp(self, end: Self, s: f64) -> Self {
glam_assert!(self.is_normalized());
glam_assert!(end.is_normalized());
let start = self;
let dot = start.dot(end);
let bias = if dot >= 0.0 { 1.0 } else { -1.0 };
let interpolated = start.add(end.mul(bias).sub(start).mul(s));
interpolated.normalize()
}
/// Performs a spherical linear interpolation between `self` and `end`
/// based on the value `s`.
///
/// When `s` is `0.0`, the result will be equal to `self`. When `s`
/// is `1.0`, the result will be equal to `end`.
///
/// # Panics
///
/// Will panic if `self` or `end` are not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn slerp(self, mut end: Self, s: f64) -> Self {
// http://number-none.com/product/Understanding%20Slerp,%20Then%20Not%20Using%20It/
glam_assert!(self.is_normalized());
glam_assert!(end.is_normalized());
const DOT_THRESHOLD: f64 = 0.9995;
// Note that a rotation can be represented by two quaternions: `q` and
// `-q`. The slerp path between `q` and `end` will be different from the
// path between `-q` and `end`. One path will take the long way around and
// one will take the short way. In order to correct for this, the `dot`
// product between `self` and `end` should be positive. If the `dot`
// product is negative, slerp between `self` and `-end`.
let mut dot = self.dot(end);
if dot < 0.0 {
end = -end;
dot = -dot;
}
if dot > DOT_THRESHOLD {
// assumes lerp returns a normalized quaternion
self.lerp(end, s)
} else {
let theta = math::acos_approx(dot);
let scale1 = math::sin(theta * (1.0 - s));
let scale2 = math::sin(theta * s);
let theta_sin = math::sin(theta);
self.mul(scale1).add(end.mul(scale2)).mul(1.0 / theta_sin)
}
}
/// Multiplies a quaternion and a 3D vector, returning the rotated vector.
///
/// # Panics
///
/// Will panic if `self` is not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn mul_vec3(self, rhs: DVec3) -> DVec3 {
glam_assert!(self.is_normalized());
let w = self.w;
let b = DVec3::new(self.x, self.y, self.z);
let b2 = b.dot(b);
rhs.mul(w * w - b2)
.add(b.mul(rhs.dot(b) * 2.0))
.add(b.cross(rhs).mul(w * 2.0))
}
/// Multiplies two quaternions. If they each represent a rotation, the result will
/// represent the combined rotation.
///
/// Note that due to floating point rounding the result may not be perfectly normalized.
///
/// # Panics
///
/// Will panic if `self` or `rhs` are not normalized when `glam_assert` is enabled.
#[inline]
#[must_use]
pub fn mul_quat(self, rhs: Self) -> Self {
glam_assert!(self.is_normalized());
glam_assert!(rhs.is_normalized());
let (x0, y0, z0, w0) = self.into();
let (x1, y1, z1, w1) = rhs.into();
Self::from_xyzw(
w0 * x1 + x0 * w1 + y0 * z1 - z0 * y1,
w0 * y1 - x0 * z1 + y0 * w1 + z0 * x1,
w0 * z1 + x0 * y1 - y0 * x1 + z0 * w1,
w0 * w1 - x0 * x1 - y0 * y1 - z0 * z1,
)
}
/// Creates a quaternion from a 3x3 rotation matrix inside a 3D affine transform.
#[inline]
#[must_use]
pub fn from_affine3(a: &crate::DAffine3) -> Self {
#[allow(clippy::useless_conversion)]
Self::from_rotation_axes(
a.matrix3.x_axis.into(),
a.matrix3.y_axis.into(),
a.matrix3.z_axis.into(),
)
}
#[inline]
#[must_use]
pub fn as_quat(self) -> Quat {
Quat::from_xyzw(self.x as f32, self.y as f32, self.z as f32, self.w as f32)
}
}
#[cfg(not(target_arch = "spirv"))]
impl fmt::Debug for DQuat {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_tuple(stringify!(DQuat))
.field(&self.x)
.field(&self.y)
.field(&self.z)
.field(&self.w)
.finish()
}
}
#[cfg(not(target_arch = "spirv"))]
impl fmt::Display for DQuat {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
if let Some(p) = f.precision() {
write!(
f,
"[{:.*}, {:.*}, {:.*}, {:.*}]",
p, self.x, p, self.y, p, self.z, p, self.w
)
} else {
write!(f, "[{}, {}, {}, {}]", self.x, self.y, self.z, self.w)
}
}
}
impl Add<DQuat> for DQuat {
type Output = Self;
/// Adds two quaternions.
///
/// The sum is not guaranteed to be normalized.
///
/// Note that addition is not the same as combining the rotations represented by the
/// two quaternions! That corresponds to multiplication.
#[inline]
fn add(self, rhs: Self) -> Self {
Self::from_vec4(DVec4::from(self) + DVec4::from(rhs))
}
}
impl Sub<DQuat> for DQuat {
type Output = Self;
/// Subtracts the `rhs` quaternion from `self`.
///
/// The difference is not guaranteed to be normalized.
#[inline]
fn sub(self, rhs: Self) -> Self {
Self::from_vec4(DVec4::from(self) - DVec4::from(rhs))
}
}
impl Mul<f64> for DQuat {
type Output = Self;
/// Multiplies a quaternion by a scalar value.
///
/// The product is not guaranteed to be normalized.
#[inline]
fn mul(self, rhs: f64) -> Self {
Self::from_vec4(DVec4::from(self) * rhs)
}
}
impl Div<f64> for DQuat {
type Output = Self;
/// Divides a quaternion by a scalar value.
/// The quotient is not guaranteed to be normalized.
#[inline]
fn div(self, rhs: f64) -> Self {
Self::from_vec4(DVec4::from(self) / rhs)
}
}
impl Mul<DQuat> for DQuat {
type Output = Self;
/// Multiplies two quaternions. If they each represent a rotation, the result will
/// represent the combined rotation.
///
/// Note that due to floating point rounding the result may not be perfectly
/// normalized.
///
/// # Panics
///
/// Will panic if `self` or `rhs` are not normalized when `glam_assert` is enabled.
#[inline]
fn mul(self, rhs: Self) -> Self {
self.mul_quat(rhs)
}
}
impl MulAssign<DQuat> for DQuat {
/// Multiplies two quaternions. If they each represent a rotation, the result will
/// represent the combined rotation.
///
/// Note that due to floating point rounding the result may not be perfectly
/// normalized.
///
/// # Panics
///
/// Will panic if `self` or `rhs` are not normalized when `glam_assert` is enabled.
#[inline]
fn mul_assign(&mut self, rhs: Self) {
*self = self.mul_quat(rhs);
}
}
impl Mul<DVec3> for DQuat {
type Output = DVec3;
/// Multiplies a quaternion and a 3D vector, returning the rotated vector.
///
/// # Panics
///
/// Will panic if `self` is not normalized when `glam_assert` is enabled.
#[inline]
fn mul(self, rhs: DVec3) -> Self::Output {
self.mul_vec3(rhs)
}
}
impl Neg for DQuat {
type Output = Self;
#[inline]
fn neg(self) -> Self {
self * -1.0
}
}
impl Default for DQuat {
#[inline]
fn default() -> Self {
Self::IDENTITY
}
}
impl PartialEq for DQuat {
#[inline]
fn eq(&self, rhs: &Self) -> bool {
DVec4::from(*self).eq(&DVec4::from(*rhs))
}
}
#[cfg(not(target_arch = "spirv"))]
impl AsRef<[f64; 4]> for DQuat {
#[inline]
fn as_ref(&self) -> &[f64; 4] {
unsafe { &*(self as *const Self as *const [f64; 4]) }
}
}
impl Sum<Self> for DQuat {
fn sum<I>(iter: I) -> Self
where
I: Iterator<Item = Self>,
{
iter.fold(Self::ZERO, Self::add)
}
}
impl<'a> Sum<&'a Self> for DQuat {
fn sum<I>(iter: I) -> Self
where
I: Iterator<Item = &'a Self>,
{
iter.fold(Self::ZERO, |a, &b| Self::add(a, b))
}
}
impl Product for DQuat {
fn product<I>(iter: I) -> Self
where
I: Iterator<Item = Self>,
{
iter.fold(Self::IDENTITY, Self::mul)
}
}
impl<'a> Product<&'a Self> for DQuat {
fn product<I>(iter: I) -> Self
where
I: Iterator<Item = &'a Self>,
{
iter.fold(Self::IDENTITY, |a, &b| Self::mul(a, b))
}
}
impl From<DQuat> for DVec4 {
#[inline]
fn from(q: DQuat) -> Self {
Self::new(q.x, q.y, q.z, q.w)
}
}
impl From<DQuat> for (f64, f64, f64, f64) {
#[inline]
fn from(q: DQuat) -> Self {
(q.x, q.y, q.z, q.w)
}
}
impl From<DQuat> for [f64; 4] {
#[inline]
fn from(q: DQuat) -> Self {
[q.x, q.y, q.z, q.w]
}
}