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

#![allow(clippy::len_without_is_empty)]

use std::ops;
use std::hash::{Hasher, Hash};

#[derive(Copy, Clone, Debug)]
#[repr(C)]
pub struct Vec2 {
    pub x: f32,
    pub y: f32,
}

impl PartialEq for Vec2 {
    fn eq(&self, other: &Self) -> bool {
        self.validate();
        self.x == other.x && self.y == other.y
    }
}

impl Eq for Vec2 {}

impl Hash for Vec2 {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.validate();
        unsafe {
            state.write(std::slice::from_raw_parts(
                self as *const Self as *const _,
                std::mem::size_of::<Self>()))
        }
    }
}

impl Default for Vec2 {
    fn default() -> Self {
        Self::ZERO
    }
}

impl Vec2 {
    pub const ZERO: Self = Vec2 { x: 0.0, y: 0.0 };
    pub const UNIT: Self = Vec2 { x: 1.0, y: 1.0 };

    fn validate(self) {
        debug_assert!(!self.x.is_nan());
        debug_assert!(!self.y.is_nan());
    }

    #[inline]
    pub const fn new(x: f32, y: f32) -> Self {
        Vec2 { x, y }
    }

    #[inline]
    pub fn dot(self, other: Self) -> f32 {
        self.x * other.x + self.y * other.y
    }

    #[inline]
    pub fn len(self) -> f32 {
        self.dot(self).sqrt()
    }

    #[inline]
    pub fn angle(self, other: Self) -> f32 {
        (self.dot(other) / (self.len() * other.len())).acos()
    }

    #[inline]
    pub fn perpendicular(self) -> Vec2 {
        Vec2 {
            x: self.y,
            y: -self.x
        }
    }

    #[inline]
    pub fn scale(self, scalar: f32) -> Vec2 {
        Vec2 {
            x: self.x * scalar,
            y: self.y * scalar
        }
    }


    /// Per component min
    pub fn min(&self, other: Self) -> Self {
        Self {
            x: self.x.min(other.x),
            y: self.y.min(other.y),
        }
    }

    /// Per component max
    pub fn max(&self, other: Self) -> Self {
        Self {
            x: self.x.max(other.x),
            y: self.y.max(other.y),
        }
    }

    #[inline]
    pub fn normalized(self) -> Option<Vec2> {
        let len = self.len();
        if len >= std::f32::EPSILON {
            let inv_len = 1.0 / len;
            return Some(Vec2 {
                x: self.x * inv_len,
                y: self.y * inv_len,
            });
        }
        None
    }
}

impl From<(f32, f32)> for Vec2 {
    fn from(v: (f32, f32)) -> Self {
        Self {
            x: v.0,
            y: v.1
        }
    }
}

impl ops::Add<Self> for Vec2 {
    type Output = Self;
    fn add(self, b: Self) -> Self {
        Self {
            x: self.x + b.x,
            y: self.y + b.y,
        }
    }
}

impl ops::AddAssign<Self> for Vec2 {
    fn add_assign(&mut self, b: Self) {
        self.x += b.x;
        self.y += b.y;
    }
}

impl ops::Sub<Self> for Vec2 {
    type Output = Self;
    fn sub(self, b: Self) -> Self {
        Self {
            x: self.x - b.x,
            y: self.y - b.y,
        }
    }
}

impl ops::SubAssign<Self> for Vec2 {
    fn sub_assign(&mut self, b: Self) {
        self.x -= b.x;
        self.y -= b.y;
    }
}