nphysics2d/utils/
generalized_cross.rs

1use na::RealField;
2use na::{Matrix2, Matrix3, RowVector2, Vector1, Vector2, Vector3};
3
4/// This is a non-standard generalization of the cross product design exclusively to group the
5/// 3D cross product and the 2D perpendicular product behind the same interface.
6pub trait GeneralizedCross {
7    /// The right-hand-side of this cross product.
8    type Rhs;
9    /// The result type of the this (non-standard) generalized cross product.
10    type CrossVector;
11    /// The matrix representation of this (non-standard) generalized cross product.
12    type CrossMatrix;
13    /// The transposed matrix representation of this (non-standard) generalized cross product.
14    type CrossMatrixTr;
15
16    /// Computes this (non-standard) generalized cross product.
17    fn gcross(&self, rhs: &Self::Rhs) -> Self::CrossVector;
18
19    /// Computes the matrix represenattion of this (non-standard) generalized cross product.
20    fn gcross_matrix(&self) -> Self::CrossMatrix;
21
22    /// Computes the transposed matrix represenattion of this (non-standard) generalized cross product.
23    fn gcross_matrix_tr(&self) -> Self::CrossMatrixTr;
24}
25
26impl<N: RealField + Copy> GeneralizedCross for Vector1<N> {
27    type Rhs = Vector2<N>;
28    type CrossVector = Vector2<N>;
29    type CrossMatrix = Matrix2<N>;
30    type CrossMatrixTr = Matrix2<N>;
31
32    #[inline]
33    fn gcross(&self, rhs: &Vector2<N>) -> Vector2<N> {
34        Vector2::new(-rhs.y * self.x, rhs.x * self.x)
35    }
36
37    #[inline]
38    fn gcross_matrix(&self) -> Matrix2<N> {
39        Matrix2::new(N::zero(), -self.x, self.x, N::zero())
40    }
41
42    #[inline]
43    fn gcross_matrix_tr(&self) -> Matrix2<N> {
44        Matrix2::new(N::zero(), self.x, -self.x, N::zero())
45    }
46}
47
48impl<N: RealField + Copy> GeneralizedCross for Vector2<N> {
49    type Rhs = Vector2<N>;
50    type CrossVector = Vector1<N>;
51    type CrossMatrix = RowVector2<N>;
52    type CrossMatrixTr = Vector2<N>;
53
54    #[inline]
55    fn gcross(&self, rhs: &Vector2<N>) -> Vector1<N> {
56        Vector1::new(self.x * rhs.y - self.y * rhs.x)
57    }
58
59    #[inline]
60    fn gcross_matrix(&self) -> RowVector2<N> {
61        RowVector2::new(-self.y, self.x)
62    }
63
64    #[inline]
65    fn gcross_matrix_tr(&self) -> Vector2<N> {
66        Vector2::new(-self.y, self.x)
67    }
68}
69
70impl<N: RealField + Copy> GeneralizedCross for Vector3<N> {
71    type Rhs = Vector3<N>;
72    type CrossVector = Vector3<N>;
73    type CrossMatrix = Matrix3<N>;
74    type CrossMatrixTr = Matrix3<N>;
75
76    #[inline]
77    fn gcross(&self, rhs: &Vector3<N>) -> Vector3<N> {
78        self.cross(rhs)
79    }
80
81    #[inline]
82    fn gcross_matrix(&self) -> Matrix3<N> {
83        self.cross_matrix()
84    }
85
86    #[inline]
87    fn gcross_matrix_tr(&self) -> Matrix3<N> {
88        Matrix3::new(
89            N::zero(),
90            self.z,
91            -self.y,
92            -self.z,
93            N::zero(),
94            self.x,
95            self.y,
96            -self.x,
97            N::zero(),
98        )
99    }
100}
nphysics2d/utils/generalized_cross.rs

nphysics2d/utils/
generalized_cross.rs
