nalgebra/src/geometry/rotation_specialization.rs

429 lines
14 KiB
Rust
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#[cfg(feature = "arbitrary")]
use base::storage::Owned;
#[cfg(feature = "arbitrary")]
use quickcheck::{Arbitrary, Gen};
use alga::general::Real;
use num::Zero;
use rand::distributions::{Distribution, Standard, OpenClosed01};
use rand::Rng;
use std::ops::Neg;
use base::dimension::{U1, U2, U3};
use base::storage::Storage;
use base::{MatrixN, Unit, Vector, Vector1, Vector3, VectorN};
use geometry::{Rotation2, Rotation3, UnitComplex};
/*
*
* 2D Rotation matrix.
*
*/
impl<N: Real> Rotation2<N> {
/// Builds a 2 dimensional rotation matrix from an angle in radian.
pub fn new(angle: N) -> Self {
let (sia, coa) = angle.sin_cos();
Self::from_matrix_unchecked(MatrixN::<N, U2>::new(coa, -sia, sia, coa))
}
/// Builds a 2 dimensional rotation matrix from an angle in radian wrapped in a 1-dimensional vector.
///
/// Equivalent to `Self::new(axisangle[0])`.
#[inline]
pub fn from_scaled_axis<SB: Storage<N, U1>>(axisangle: Vector<N, U1, SB>) -> Self {
Self::new(axisangle[0])
}
/// The rotation matrix required to align `a` and `b` but with its angle.
///
/// This is the rotation `R` such that `(R * a).angle(b) == 0 && (R * a).dot(b).is_positive()`.
#[inline]
pub fn rotation_between<SB, SC>(a: &Vector<N, U2, SB>, b: &Vector<N, U2, SC>) -> Self
where
SB: Storage<N, U2>,
SC: Storage<N, U2>,
{
::convert(UnitComplex::rotation_between(a, b).to_rotation_matrix())
}
/// The smallest rotation needed to make `a` and `b` collinear and point toward the same
/// direction, raised to the power `s`.
#[inline]
pub fn scaled_rotation_between<SB, SC>(
a: &Vector<N, U2, SB>,
b: &Vector<N, U2, SC>,
s: N,
) -> Self
where
SB: Storage<N, U2>,
SC: Storage<N, U2>,
{
::convert(UnitComplex::scaled_rotation_between(a, b, s).to_rotation_matrix())
}
}
impl<N: Real> Rotation2<N> {
/// The rotation angle.
#[inline]
pub fn angle(&self) -> N {
self.matrix()[(1, 0)].atan2(self.matrix()[(0, 0)])
}
/// The rotation angle needed to make `self` and `other` coincide.
#[inline]
pub fn angle_to(&self, other: &Rotation2<N>) -> N {
self.rotation_to(other).angle()
}
/// The rotation matrix needed to make `self` and `other` coincide.
///
/// The result is such that: `self.rotation_to(other) * self == other`.
#[inline]
pub fn rotation_to(&self, other: &Rotation2<N>) -> Rotation2<N> {
other * self.inverse()
}
/// Raise the quaternion to a given floating power, i.e., returns the rotation with the angle
/// of `self` multiplied by `n`.
#[inline]
pub fn powf(&self, n: N) -> Rotation2<N> {
Self::new(self.angle() * n)
}
/// The rotation angle returned as a 1-dimensional vector.
#[inline]
pub fn scaled_axis(&self) -> VectorN<N, U1> {
Vector1::new(self.angle())
}
}
impl<N: Real> Distribution<Rotation2<N>> for Standard
where
OpenClosed01: Distribution<N>,
{
/// Generate a uniformly distributed random rotation.
#[inline]
fn sample<'a, R: Rng + ?Sized>(&self, rng: &'a mut R) -> Rotation2<N> {
Rotation2::new(rng.sample(OpenClosed01) * N::two_pi())
}
}
#[cfg(feature = "arbitrary")]
impl<N: Real + Arbitrary> Arbitrary for Rotation2<N>
where
Owned<N, U2, U2>: Send,
{
#[inline]
fn arbitrary<G: Gen>(g: &mut G) -> Self {
Self::new(N::arbitrary(g))
}
}
/*
*
* 3D Rotation matrix.
*
*/
impl<N: Real> Rotation3<N> {
/// Builds a 3 dimensional rotation matrix from an axis and an angle.
///
/// # Arguments
/// * `axisangle` - A vector representing the rotation. Its magnitude is the amount of rotation
/// in radian. Its direction is the axis of rotation.
pub fn new<SB: Storage<N, U3>>(axisangle: Vector<N, U3, SB>) -> Self {
let axisangle = axisangle.into_owned();
let (axis, angle) = Unit::new_and_get(axisangle);
Self::from_axis_angle(&axis, angle)
}
/// Builds a 3D rotation matrix from an axis scaled by the rotation angle.
pub fn from_scaled_axis<SB: Storage<N, U3>>(axisangle: Vector<N, U3, SB>) -> Self {
Self::new(axisangle)
}
/// Builds a 3D rotation matrix from an axis and a rotation angle.
pub fn from_axis_angle<SB>(axis: &Unit<Vector<N, U3, SB>>, angle: N) -> Self
where
SB: Storage<N, U3>,
{
if angle.is_zero() {
Self::identity()
} else {
let ux = axis.as_ref()[0];
let uy = axis.as_ref()[1];
let uz = axis.as_ref()[2];
let sqx = ux * ux;
let sqy = uy * uy;
let sqz = uz * uz;
let (sin, cos) = angle.sin_cos();
let one_m_cos = N::one() - cos;
Self::from_matrix_unchecked(MatrixN::<N, U3>::new(
sqx + (N::one() - sqx) * cos,
ux * uy * one_m_cos - uz * sin,
ux * uz * one_m_cos + uy * sin,
ux * uy * one_m_cos + uz * sin,
sqy + (N::one() - sqy) * cos,
uy * uz * one_m_cos - ux * sin,
ux * uz * one_m_cos - uy * sin,
uy * uz * one_m_cos + ux * sin,
sqz + (N::one() - sqz) * cos,
))
}
}
/// Creates a new rotation from Euler angles.
///
/// The primitive rotations are applied in order: 1 roll 2 pitch 3 yaw.
pub fn from_euler_angles(roll: N, pitch: N, yaw: N) -> Self {
let (sr, cr) = roll.sin_cos();
let (sp, cp) = pitch.sin_cos();
let (sy, cy) = yaw.sin_cos();
Self::from_matrix_unchecked(MatrixN::<N, U3>::new(
cy * cp,
cy * sp * sr - sy * cr,
cy * sp * cr + sy * sr,
sy * cp,
sy * sp * sr + cy * cr,
sy * sp * cr - cy * sr,
-sp,
cp * sr,
cp * cr,
))
}
/// Creates Euler angles from a rotation.
///
/// The angles are produced in the form (roll, yaw, pitch).
pub fn to_euler_angles(&self) -> (N, N, N) {
// Implementation informed by "Computing Euler angles from a rotation matrix", by Gregory G. Slabaugh
// http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.371.6578
if self[(2, 0)].abs() != N::one() {
let yaw = -self[(2, 0)].asin();
let roll = (self[(2, 1)] / yaw.cos()).atan2(self[(2, 2)] / yaw.cos());
let pitch = (self[(1, 0)] / yaw.cos()).atan2(self[(0, 0)] / yaw.cos());
(roll, yaw, pitch)
} else if self[(2, 0)] == -N::one() {
(self[(0, 1)].atan2(self[(0, 2)]), N::frac_pi_2(), N::zero())
} else {
(
-self[(0, 1)].atan2(-self[(0, 2)]),
-N::frac_pi_2(),
N::zero(),
)
}
}
/// Creates a rotation that corresponds to the local frame of an observer standing at the
/// origin and looking toward `dir`.
///
/// It maps the view direction `dir` to the positive `z` axis.
///
/// # Arguments
/// * dir - The look direction, that is, direction the matrix `z` axis will be aligned with.
/// * up - The vertical direction. The only requirement of this parameter is to not be
/// collinear
/// to `dir`. Non-collinearity is not checked.
#[inline]
pub fn new_observer_frame<SB, SC>(dir: &Vector<N, U3, SB>, up: &Vector<N, U3, SC>) -> Self
where
SB: Storage<N, U3>,
SC: Storage<N, U3>,
{
let zaxis = dir.normalize();
let xaxis = up.cross(&zaxis).normalize();
let yaxis = zaxis.cross(&xaxis).normalize();
Self::from_matrix_unchecked(MatrixN::<N, U3>::new(
xaxis.x, yaxis.x, zaxis.x, xaxis.y, yaxis.y, zaxis.y, xaxis.z, yaxis.z, zaxis.z,
))
}
/// Builds a right-handed look-at view matrix without translation.
///
/// This conforms to the common notion of right handed look-at matrix from the computer
/// graphics community.
///
/// # Arguments
/// * dir - The direction toward which the camera looks.
/// * up - A vector approximately aligned with required the vertical axis. The only
/// requirement of this parameter is to not be collinear to `target - eye`.
#[inline]
pub fn look_at_rh<SB, SC>(dir: &Vector<N, U3, SB>, up: &Vector<N, U3, SC>) -> Self
where
SB: Storage<N, U3>,
SC: Storage<N, U3>,
{
Self::new_observer_frame(&dir.neg(), up).inverse()
}
/// Builds a left-handed look-at view matrix without translation.
///
/// This conforms to the common notion of left handed look-at matrix from the computer
/// graphics community.
///
/// # Arguments
/// * dir - The direction toward which the camera looks.
/// * up - A vector approximately aligned with required the vertical axis. The only
/// requirement of this parameter is to not be collinear to `target - eye`.
#[inline]
pub fn look_at_lh<SB, SC>(dir: &Vector<N, U3, SB>, up: &Vector<N, U3, SC>) -> Self
where
SB: Storage<N, U3>,
SC: Storage<N, U3>,
{
Self::new_observer_frame(dir, up).inverse()
}
/// The rotation matrix required to align `a` and `b` but with its angle.
///
/// This is the rotation `R` such that `(R * a).angle(b) == 0 && (R * a).dot(b).is_positive()`.
#[inline]
pub fn rotation_between<SB, SC>(a: &Vector<N, U3, SB>, b: &Vector<N, U3, SC>) -> Option<Self>
where
SB: Storage<N, U3>,
SC: Storage<N, U3>,
{
Self::scaled_rotation_between(a, b, N::one())
}
/// The smallest rotation needed to make `a` and `b` collinear and point toward the same
/// direction, raised to the power `s`.
#[inline]
pub fn scaled_rotation_between<SB, SC>(
a: &Vector<N, U3, SB>,
b: &Vector<N, U3, SC>,
n: N,
) -> Option<Self>
where
SB: Storage<N, U3>,
SC: Storage<N, U3>,
{
// FIXME: code duplication with Rotation.
if let (Some(na), Some(nb)) = (a.try_normalize(N::zero()), b.try_normalize(N::zero())) {
let c = na.cross(&nb);
if let Some(axis) = Unit::try_new(c, N::default_epsilon()) {
return Some(Self::from_axis_angle(&axis, na.dot(&nb).acos() * n));
}
// Zero or PI.
if na.dot(&nb) < N::zero() {
// PI
//
// The rotation axis is undefined but the angle not zero. This is not a
// simple rotation.
return None;
}
}
Some(Self::identity())
}
/// The rotation angle.
#[inline]
pub fn angle(&self) -> N {
((self.matrix()[(0, 0)] + self.matrix()[(1, 1)] + self.matrix()[(2, 2)] - N::one())
/ ::convert(2.0))
.acos()
}
/// The rotation axis. Returns `None` if the rotation angle is zero or PI.
#[inline]
pub fn axis(&self) -> Option<Unit<Vector3<N>>> {
let axis = VectorN::<N, U3>::new(
self.matrix()[(2, 1)] - self.matrix()[(1, 2)],
self.matrix()[(0, 2)] - self.matrix()[(2, 0)],
self.matrix()[(1, 0)] - self.matrix()[(0, 1)],
);
Unit::try_new(axis, N::default_epsilon())
}
/// The rotation axis multiplied by the rotation angle.
#[inline]
pub fn scaled_axis(&self) -> Vector3<N> {
if let Some(axis) = self.axis() {
axis.unwrap() * self.angle()
} else {
Vector::zero()
}
}
/// The rotation angle needed to make `self` and `other` coincide.
#[inline]
pub fn angle_to(&self, other: &Rotation3<N>) -> N {
self.rotation_to(other).angle()
}
/// The rotation matrix needed to make `self` and `other` coincide.
///
/// The result is such that: `self.rotation_to(other) * self == other`.
#[inline]
pub fn rotation_to(&self, other: &Rotation3<N>) -> Rotation3<N> {
other * self.inverse()
}
/// Raise the quaternion to a given floating power, i.e., returns the rotation with the same
/// axis as `self` and an angle equal to `self.angle()` multiplied by `n`.
#[inline]
pub fn powf(&self, n: N) -> Rotation3<N> {
if let Some(axis) = self.axis() {
Self::from_axis_angle(&axis, self.angle() * n)
} else if self.matrix()[(0, 0)] < N::zero() {
let minus_id = MatrixN::<N, U3>::from_diagonal_element(-N::one());
Self::from_matrix_unchecked(minus_id)
} else {
Self::identity()
}
}
}
impl<N: Real> Distribution<Rotation3<N>> for Standard
where
OpenClosed01: Distribution<N>,
{
/// Generate a uniformly distributed random rotation.
#[inline]
fn sample<'a, R: Rng + ?Sized>(&self, rng: &mut R) -> Rotation3<N> {
// James Arvo.
// Fast random rotation matrices.
// In D. Kirk, editor, Graphics Gems III, pages 117-120. Academic, New York, 1992.
// Compute a random rotation around Z
let theta = N::two_pi() * rng.sample(OpenClosed01);
let (ts, tc) = theta.sin_cos();
let a = MatrixN::<N, U3>::new(
tc, ts, N::zero(),
-ts, tc, N::zero(),
N::zero(), N::zero(), N::one()
);
// Compute a random rotation *of* Z
let phi = N::two_pi() * rng.sample(OpenClosed01);
let z = rng.sample(OpenClosed01);
let (ps, pc) = phi.sin_cos();
let sqrt_z = z.sqrt();
let v = Vector3::new(pc * sqrt_z, ps * sqrt_z, (N::one() - z).sqrt());
let mut b = v * v.transpose();
b += b;
b -= MatrixN::<N, U3>::identity();
Rotation3::from_matrix_unchecked(b * a)
}
}
#[cfg(feature = "arbitrary")]
impl<N: Real + Arbitrary> Arbitrary for Rotation3<N>
where
Owned<N, U3, U3>: Send,
Owned<N, U3>: Send,
{
#[inline]
fn arbitrary<G: Gen>(g: &mut G) -> Self {
Self::new(VectorN::arbitrary(g))
}
}