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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159

use std::f32;
use std::ops::{Add, Sub, Mul, Div, Neg, Index, IndexMut};

use linalg::Point;

/// Vector is a standard 3 component vector
#[derive(Debug, Copy, Clone, PartialEq, PartialOrd)]
pub struct Vector {
    pub x: f32,
    pub y: f32,
    pub z: f32,
}

impl Vector {
    /// Initialize the vector and set values for x, y, z
    pub fn new(x: f32, y: f32, z: f32) -> Vector {
        Vector { x: x, y: y, z: z }
    }
    /// Initialize the vector with the same value of x, y, z
    pub fn broadcast(x: f32) -> Vector {
        Vector { x: x, y: x, z: x }
    }
    /// Compute the squared length of the vector
    pub fn length_sqr(&self) -> f32 {
        self.x * self.x + self.y * self.y + self.z * self.z
    }
    /// Compute the length of the vector
    pub fn length(&self) -> f32 {
        f32::sqrt(self.length_sqr())
    }
    /// Get a normalized copy of this vector
    pub fn normalized(&self) -> Vector {
        let len = self.length();
        Vector { x: self.x / len, y: self.y / len, z: self.z / len }
    }
}

impl Add for Vector {
    type Output = Vector;
    /// Add two vectors together
    fn add(self, rhs: Vector) -> Vector {
        Vector { x: self.x + rhs.x, y: self.y + rhs.y, z: self.z + rhs.z }
    }
}

impl Sub for Vector {
    type Output = Vector;
    /// Subtract two vectors
    fn sub(self, rhs: Vector) -> Vector {
        Vector { x: self.x - rhs.x, y: self.y - rhs.y, z: self.z - rhs.z }
    }
}

impl Mul for Vector {
    type Output = Vector;
    /// Multiply two vectors
    fn mul(self, rhs: Vector) -> Vector {
        Vector { x: self.x * rhs.x, y: self.y * rhs.y, z: self.z * rhs.z }
    }
}

impl Mul<f32> for Vector {
    type Output = Vector;
    /// Scale the vector by some value
    fn mul(self, rhs: f32) -> Vector {
        Vector { x: self.x * rhs, y: self.y * rhs, z: self.z * rhs }
    }
}

impl Mul<Vector> for f32 {
    type Output = Vector;
    /// Scale the vector by some value
    fn mul(self, rhs: Vector) -> Vector {
        Vector { x: self * rhs.x, y: self * rhs.y, z: self * rhs.z }
    }
}

impl Mul<Point> for Vector {
    type Output = Point;
    /// Scale the vector by some value
    fn mul(self, rhs: Point) -> Point {
        Point { x: self.x * rhs.x, y: self.y * rhs.y, z: self.z * rhs.z }
    }
}

impl Div for Vector {
    type Output = Vector;
    /// Divide the vectors components by the right hand side's components
    fn div(self, rhs: Vector) -> Vector {
        Vector { x: self.x / rhs.x, y: self.y / rhs.y, z: self.z / rhs.z }
    }
}

impl Div<f32> for Vector {
    type Output = Vector;
    /// Divide the vectors components by a scalar
    fn div(self, rhs: f32) -> Vector {
        Vector { x: self.x / rhs, y: self.y / rhs, z: self.z / rhs }
    }
}

impl Neg for Vector {
    type Output = Vector;
    /// Negate the vector
    fn neg(self) -> Vector {
        Vector { x: -self.x, y: -self.y, z: -self.z }
    }
}

impl Index<usize> for Vector {
    type Output = f32;
    /// Access the vector by index
    ///
    /// - 0 = x
    /// - 1 = y
    /// - 2 = z
    fn index(&self, i: usize) -> &f32 {
        match i {
            0 => &self.x,
            1 => &self.y,
            2 => &self.z,
            _ => panic!("Invalid index into vector"),
        }
    }
}

impl IndexMut<usize> for Vector {
    /// Access the vector by index
    ///
    /// - 0 = x
    /// - 1 = y
    /// - 2 = z
    fn index_mut(&mut self, i: usize) -> &mut f32 {
        match i {
            0 => &mut self.x,
            1 => &mut self.y,
            2 => &mut self.z,
            _ => panic!("Invalid index into vector"),
        }
    }
}

#[test]
fn test_len_sqr() {
    let v = Vector::new(1f32, 2f32, 3f32);
    assert!(v.length_sqr() == 1f32 + 4f32 + 9f32);
}

#[test]
fn test_idx() {
    let mut v = Vector::new(1f32, 2f32, 3f32);
    assert!(v[0] == 1f32 && v[1] == 2f32 && v[2] == 3f32);
    {
        let x = &mut v[1];
        *x = 5f32;
    }
    assert!(v[1] == 5f32);
}