1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

use cgmath;
use mint;
use std::{mem, ops};

use approx::ApproxEq;
use cgmath::SquareMatrix;
use Vec2;

/// 2x2 column major matrix.
#[derive(Clone, Copy, Debug, PartialEq)]
#[repr(C)]
pub struct Mat2(pub(crate) cgmath::Matrix2<f32>);

impl Mat2 {
    /// Returns the identity matrix.
    pub fn identity() -> Self {
        Mat2(cgmath::Matrix2::identity())
    }

    /// Computes the inverse of this matrix.
    ///
    /// # Panics
    ///
    /// Panics if the matrix is not invertible.
    pub fn invert(self) -> Mat2 {
        self.try_invert().unwrap()
    }

    /// Computes the inverse of this matrix, returning `None` if non-invertible.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # #[macro_use] extern crate euler;
    /// # fn main() {
    /// let m = mat2!();
    /// assert_eq!(m.try_invert(), Some(mat2!()));
    /// # }
    /// ```
    ///
    /// ```rust
    /// # #[macro_use] extern crate euler;
    /// # fn main() {
    /// let m = mat2!(
    ///     0.0, 0.0,
    ///     0.0, 0.0,
    /// );
    /// assert_eq!(m.try_invert(), None);
    /// # }
    /// ```
    pub fn try_invert(self) -> Option<Mat2> {
        self.0.invert().map(Mat2)
    }
}

impl AsRef<[[f32; 2]; 2]> for Mat2 {
    fn as_ref(&self) -> &[[f32; 2]; 2] {
        unsafe {
            mem::transmute(self)
        }
    }
}

impl From<cgmath::Matrix2<f32>> for Mat2 {
    fn from(m: cgmath::Matrix2<f32>) -> Self {
        Mat2(m)
    }
}

impl From<[[f32; 2]; 2]> for Mat2 {
    fn from(m: [[f32; 2]; 2]) -> Self {
        Mat2(m.into())
    }
}

impl Into<[[f32; 2]; 2]> for Mat2 {
    fn into(self) -> [[f32; 2]; 2] {
        self.0.into()
    }
}

impl ops::Mul<Mat2> for Mat2 {
    type Output = Mat2;
    fn mul(self, rhs: Mat2) -> Self::Output {
        Mat2(self.0 * rhs.0)
    }
}

impl ops::Mul<Vec2> for Mat2 {
    type Output = Vec2;
    fn mul(self, rhs: Vec2) -> Self::Output {
        let v = self.0 * cgmath::Vector2::new(rhs.x, rhs.y);
        vec2!(v.x, v.y)
    }
}

impl<'a> ops::Mul<Vec2> for &'a Mat2 {
    type Output = Vec2;
    fn mul(self, rhs: Vec2) -> Self::Output {
        (*self).mul(rhs)
    }
}

impl ApproxEq for Mat2 {
    type Epsilon = <f32 as ApproxEq>::Epsilon;

    fn default_epsilon() -> Self::Epsilon {
        <f32 as ApproxEq>::default_epsilon()
    }

    fn default_max_relative() -> Self::Epsilon {
        <f32 as ApproxEq>::default_max_relative()
    }

    fn default_max_ulps() -> u32 {
        <f32 as ApproxEq>::default_max_ulps()
    }

    fn relative_eq(
        &self,
        other: &Self,
        epsilon: Self::Epsilon,
        max_relative: Self::Epsilon,
    ) -> bool {
        self.0.relative_eq(&other.0, epsilon, max_relative)
    }

    fn ulps_eq(&self, other: &Self, epsilon: Self::Epsilon, max_ulps: u32) -> bool {
        self.0.ulps_eq(&other.0, epsilon, max_ulps)
    }
}

impl From<mint::ColumnMatrix2<f32>> for Mat2 {
    fn from(m: mint::ColumnMatrix2<f32>) -> Self {
        Mat2(m.into())
    }
}

impl Into<mint::ColumnMatrix2<f32>> for Mat2 {
    fn into(self) -> mint::ColumnMatrix2<f32> {
        self.0.into()
    }
}