diff --git a/.gitignore b/.gitignore index 84b112d0..17a97cc7 100644 --- a/.gitignore +++ b/.gitignore @@ -7,3 +7,4 @@ target/ Cargo.lock *.orig *.swo +site/ \ No newline at end of file diff --git a/CHANGELOG.md b/CHANGELOG.md index d272d63c..d8eacebb 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -4,6 +4,14 @@ documented here. This project adheres to [Semantic Versioning](http://semver.org/). +## [0.15.0] - WIP +### Modified +### Added + * Add methods `.rotation_between_axis(...)` and `.scaled_rotation_between_axis(...)` to `UnitComplex` + to compute the rotation matrix between two 2D **unit** vectors. + * Add methods `.axis_angle()` to `UnitComplex` and `UnitQuaternion` in order to retrieve both the + unit rotation axis and the rotation angle simultaneously. + ## [0.14.0] ### Modified * Allow the `Isometry * Unit` multiplication. diff --git a/src/core/blas.rs b/src/core/blas.rs index 91035199..de8020ec 100644 --- a/src/core/blas.rs +++ b/src/core/blas.rs @@ -462,8 +462,7 @@ where let (nrows3, ncols3) = b.shape(); assert_eq!( - ncols2, - nrows3, + ncols2, nrows3, "gemm: dimensions mismatch for multiplication." ); assert_eq!( @@ -564,8 +563,7 @@ where let (nrows3, ncols3) = b.shape(); assert_eq!( - nrows2, - nrows3, + nrows2, nrows3, "gemm: dimensions mismatch for multiplication." ); assert_eq!( diff --git a/src/geometry/quaternion.rs b/src/geometry/quaternion.rs index 1a70c541..88ad945d 100644 --- a/src/geometry/quaternion.rs +++ b/src/geometry/quaternion.rs @@ -491,6 +491,18 @@ impl UnitQuaternion { } } + /// The rotation axis and angle in ]0, pi] of this unit quaternion. + /// + /// Returns `None` if the angle is zero. + #[inline] + pub fn axis_angle(&self) -> Option<(Unit>, N)> { + if let Some(axis) = self.axis() { + Some((axis, self.angle())) + } else { + None + } + } + /// Compute the exponential of a quaternion. /// /// Note that this function yields a `Quaternion` because it looses the unit property. diff --git a/src/geometry/unit_complex.rs b/src/geometry/unit_complex.rs index 299e5d0b..07c7cdca 100644 --- a/src/geometry/unit_complex.rs +++ b/src/geometry/unit_complex.rs @@ -34,6 +34,22 @@ impl UnitComplex { Vector1::new(self.angle()) } + /// The rotation axis and angle in ]0, pi] of this complex number. + /// + /// Returns `None` if the angle is zero. + #[inline] + pub fn axis_angle(&self) -> Option<(Unit>, N)> { + let ang = self.angle(); + + if ang.is_zero() { + None + } else if ang.is_sign_negative() { + Some((Unit::new_unchecked(Vector1::x()), -ang)) + } else { + Some((Unit::new_unchecked(-Vector1::::x()), ang)) + } + } + /// The underlying complex number. /// /// Same as `self.as_ref()`. diff --git a/src/geometry/unit_complex_construction.rs b/src/geometry/unit_complex_construction.rs index 73d0ccdd..4ea268f5 100644 --- a/src/geometry/unit_complex_construction.rs +++ b/src/geometry/unit_complex_construction.rs @@ -6,7 +6,7 @@ use num_complex::Complex; use rand::{Rand, Rng}; use alga::general::Real; -use core::{DefaultAllocator, Vector}; +use core::{DefaultAllocator, Unit, Vector}; use core::dimension::{U1, U2}; use core::storage::Storage; use core::allocator::Allocator; @@ -99,15 +99,48 @@ impl UnitComplex { SB: Storage, SC: Storage, { - if let (Some(na), Some(nb)) = (a.try_normalize(N::zero()), b.try_normalize(N::zero())) { - let sang = na.perp(&nb); - let cang = na.dot(&nb); - - Self::from_angle(sang.atan2(cang) * s) + // FIXME: code duplication with Rotation. + if let (Some(na), Some(nb)) = ( + Unit::try_new(a.clone_owned(), N::zero()), + Unit::try_new(b.clone_owned(), N::zero()), + ) { + Self::scaled_rotation_between_axis(&na, &nb, s) } else { Self::identity() } } + + /// The unit complex needed to make `a` and `b` be collinear and point toward the same + /// direction. + #[inline] + pub fn rotation_between_axis( + a: &Unit>, + b: &Unit>, + ) -> Self + where + SB: Storage, + SC: Storage, + { + Self::scaled_rotation_between_axis(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_axis( + na: &Unit>, + nb: &Unit>, + s: N, + ) -> Self + where + SB: Storage, + SC: Storage, + { + let sang = na.perp(&nb); + let cang = na.dot(&nb); + + Self::from_angle(sang.atan2(cang) * s) + } } impl One for UnitComplex {