| 1 | use std::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign, Neg}; |
| 2 | |
| 3 | pub type Nanoseconds = u64; |
| 4 | |
| 5 | #[macro_export] |
| 6 | macro_rules! point { |
| 7 | ( $x:expr, $y:expr ) => { |
| 8 | Point2D { x: $x, y: $y } |
| 9 | }; |
| 10 | } |
| 11 | |
| 12 | #[derive(Debug, Default, Copy, Clone, PartialEq)] |
| 13 | pub struct Point2D<T> { |
| 14 | pub x: T, |
| 15 | pub y: T, |
| 16 | } |
| 17 | |
| 18 | impl Point2D<f64> { |
| 19 | pub fn length(self) -> f64 { |
| 20 | ((self.x * self.x) + (self.y * self.y)).sqrt() |
| 21 | } |
| 22 | } |
| 23 | |
| 24 | macro_rules! point_op { |
| 25 | ($op:tt, $trait:ident($fn:ident), $trait_assign:ident($fn_assign:ident), $rhs:ident = $Rhs:ty => $x:expr, $y:expr) => { |
| 26 | impl<T: $trait<Output = T>> $trait<$Rhs> for Point2D<T> { |
| 27 | type Output = Self; |
| 28 | |
| 29 | fn $fn(self, $rhs: $Rhs) -> Self { |
| 30 | Self { |
| 31 | x: self.x $op $x, |
| 32 | y: self.y $op $y, |
| 33 | } |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | impl<T: $trait<Output = T> + Copy> $trait_assign<$Rhs> for Point2D<T> { |
| 38 | fn $fn_assign(&mut self, $rhs: $Rhs) { |
| 39 | *self = Self { |
| 40 | x: self.x $op $x, |
| 41 | y: self.y $op $y, |
| 42 | } |
| 43 | } |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | point_op!(+, Add(add), AddAssign(add_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 49 | point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 50 | point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 51 | point_op!(/, Div(div), DivAssign(div_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 52 | point_op!(+, Add(add), AddAssign(add_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 53 | point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 54 | point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 55 | point_op!(/, Div(div), DivAssign(div_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 56 | |
| 57 | ////////// multiply point with scalar ////////////////////////////////////////// |
| 58 | impl<T: Mul<Output = T> + Copy> Mul<T> for Point2D<T> { |
| 59 | type Output = Self; |
| 60 | |
| 61 | fn mul(self, rhs: T) -> Self { |
| 62 | Self { |
| 63 | x: self.x * rhs, |
| 64 | y: self.y * rhs, |
| 65 | } |
| 66 | } |
| 67 | } |
| 68 | |
| 69 | impl<T: Mul<Output = T> + Copy> MulAssign<T> for Point2D<T> { |
| 70 | fn mul_assign(&mut self, rhs: T) { |
| 71 | *self = Self { |
| 72 | x: self.x * rhs, |
| 73 | y: self.y * rhs, |
| 74 | } |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | ////////// divide point with scalar //////////////////////////////////////////// |
| 79 | impl<T: Div<Output = T> + Copy> Div<T> for Point2D<T> { |
| 80 | type Output = Self; |
| 81 | |
| 82 | fn div(self, rhs: T) -> Self { |
| 83 | Self { |
| 84 | x: self.x / rhs, |
| 85 | y: self.y / rhs, |
| 86 | } |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | impl<T: Div<Output = T> + Copy> DivAssign<T> for Point2D<T> { |
| 91 | fn div_assign(&mut self, rhs: T) { |
| 92 | *self = Self { |
| 93 | x: self.x / rhs, |
| 94 | y: self.y / rhs, |
| 95 | } |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | impl<T: Neg<Output = T>> Neg for Point2D<T> { |
| 100 | type Output = Self; |
| 101 | |
| 102 | fn neg(self) -> Self { |
| 103 | Self { |
| 104 | x: -self.x, |
| 105 | y: -self.y, |
| 106 | } |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | impl<T> From<(T, T)> for Point2D<T> { |
| 111 | fn from(item: (T, T)) -> Self { |
| 112 | Point2D { |
| 113 | x: item.0, |
| 114 | y: item.1, |
| 115 | } |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | impl From<Degrees> for Point2D<f64> { |
| 120 | fn from(item: Degrees) -> Self { |
| 121 | Point2D { |
| 122 | x: (item.0 * std::f64::consts::PI / 180.0).cos(), |
| 123 | y: (item.0 * std::f64::consts::PI / 180.0).sin(), |
| 124 | } |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | impl From<Radians> for Point2D<f64> { |
| 129 | fn from(item: Radians) -> Self { |
| 130 | Point2D { |
| 131 | x: item.0.cos(), |
| 132 | y: item.0.sin(), |
| 133 | } |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | #[derive(Debug, PartialEq, Clone, Copy)] |
| 138 | struct Degrees(f64); |
| 139 | #[derive(Debug, PartialEq, Clone, Copy)] |
| 140 | struct Radians(f64); |
| 141 | |
| 142 | impl Degrees { |
| 143 | fn to_radians(&self) -> Radians { |
| 144 | Radians(self.0 * std::f64::consts::PI / 180.0) |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | impl Radians { |
| 149 | fn to_degrees(&self) -> Degrees { |
| 150 | Degrees(self.0 * 180.0 * std::f64::consts::FRAC_1_PI) |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | #[macro_export] |
| 155 | macro_rules! rect { |
| 156 | ( $x:expr, $y:expr ) => { |
| 157 | Rect { x: $x, y: $y } |
| 158 | }; |
| 159 | } |
| 160 | |
| 161 | #[derive(Default)] |
| 162 | pub struct Rect<T> { |
| 163 | pub width: T, |
| 164 | pub height: T, |
| 165 | } |
| 166 | |
| 167 | impl<T: Mul<Output = T> + Copy> Rect<T> { |
| 168 | #[allow(dead_code)] |
| 169 | pub fn area(&self) -> T { |
| 170 | self.width * self.height |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | impl<T> From<(T, T)> for Rect<T> { |
| 175 | fn from(item: (T, T)) -> Self { |
| 176 | Rect { |
| 177 | width: item.0, |
| 178 | height: item.1, |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | #[cfg(test)] |
| 184 | mod tests { |
| 185 | use super::*; |
| 186 | |
| 187 | #[test] |
| 188 | fn immutable_copy_of_point() { |
| 189 | let a = point!(0, 0); |
| 190 | let mut b = a; // Copy |
| 191 | assert_eq!(a, b); // PartialEq |
| 192 | b.x = 1; |
| 193 | assert_ne!(a, b); // PartialEq |
| 194 | } |
| 195 | |
| 196 | #[test] |
| 197 | fn add_points() { |
| 198 | let mut a = point!(1, 0); |
| 199 | assert_eq!(a + point!(2, 2), point!(3, 2)); // Add |
| 200 | a += point!(2, 2); // AddAssign |
| 201 | assert_eq!(a, point!(3, 2)); |
| 202 | assert_eq!(point!(1, 0) + (2, 3), point!(3, 3)); |
| 203 | } |
| 204 | |
| 205 | #[test] |
| 206 | fn sub_points() { |
| 207 | let mut a = point!(1, 0); |
| 208 | assert_eq!(a - point!(2, 2), point!(-1, -2)); |
| 209 | a -= point!(2, 2); |
| 210 | assert_eq!(a, point!(-1, -2)); |
| 211 | assert_eq!(point!(1, 0) - (2, 3), point!(-1, -3)); |
| 212 | } |
| 213 | |
| 214 | #[test] |
| 215 | fn mul_points() { |
| 216 | let mut a = point!(1, 2); |
| 217 | assert_eq!(a * 2, point!(2, 4)); |
| 218 | assert_eq!(a * point!(2, 3), point!(2, 6)); |
| 219 | a *= 2; |
| 220 | assert_eq!(a, point!(2, 4)); |
| 221 | a *= point!(3, 1); |
| 222 | assert_eq!(a, point!(6, 4)); |
| 223 | assert_eq!(point!(1, 0) * (2, 3), point!(2, 0)); |
| 224 | } |
| 225 | |
| 226 | #[test] |
| 227 | fn div_points() { |
| 228 | let mut a = point!(4, 8); |
| 229 | assert_eq!(a / 2, point!(2, 4)); |
| 230 | assert_eq!(a / point!(2, 4), point!(2, 2)); |
| 231 | a /= 2; |
| 232 | assert_eq!(a, point!(2, 4)); |
| 233 | a /= point!(2, 4); |
| 234 | assert_eq!(a, point!(1, 1)); |
| 235 | assert_eq!(point!(6, 3) / (2, 3), point!(3, 1)); |
| 236 | } |
| 237 | |
| 238 | #[test] |
| 239 | fn neg_point() { |
| 240 | assert_eq!(point!(1, 1), -point!(-1, -1)); |
| 241 | } |
| 242 | |
| 243 | #[test] |
| 244 | fn angles() { |
| 245 | assert_eq!(Radians(0.0).to_degrees(), Degrees(0.0)); |
| 246 | assert_eq!(Radians(std::f64::consts::PI).to_degrees(), Degrees(180.0)); |
| 247 | assert_eq!(Degrees(180.0).to_radians(), Radians(std::f64::consts::PI)); |
| 248 | assert!((Point2D::from(Degrees(90.0)) - point!(0.0, 1.0)).length() < 0.001); |
| 249 | assert!((Point2D::from(Radians(std::f64::consts::FRAC_PI_2)) - point!(0.0, 1.0)).length() < 0.001); |
| 250 | } |
| 251 | |
| 252 | #[test] |
| 253 | fn area_for_rect_of_multipliable_type() { |
| 254 | let r: Rect<_> = (30, 20).into(); // the Into trait uses the From trait |
| 255 | assert_eq!(r.area(), 30 * 20); |
| 256 | // let a = Rect::from(("a".to_string(), "b".to_string())).area(); // this doesn't work, because area() is not implemented for String |
| 257 | } |
| 258 | } |