| 1 | use std::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign, Neg}; |
| 2 | |
| 3 | #[macro_export] |
| 4 | macro_rules! point { |
| 5 | ( $x:expr, $y:expr ) => { |
| 6 | Point2D { x: $x, y: $y } |
| 7 | }; |
| 8 | } |
| 9 | |
| 10 | #[derive(Debug, Default, Copy, Clone, PartialEq)] |
| 11 | pub struct Point2D<T> { |
| 12 | pub x: T, |
| 13 | pub y: T, |
| 14 | } |
| 15 | |
| 16 | impl Point2D<f64> { |
| 17 | pub fn length(self) -> f64 { |
| 18 | ((self.x * self.x) + (self.y * self.y)).sqrt() |
| 19 | } |
| 20 | |
| 21 | pub fn to_i32(self) -> Point2D<i32> { |
| 22 | Point2D { |
| 23 | x: self.x as i32, |
| 24 | y: self.y as i32, |
| 25 | } |
| 26 | } |
| 27 | } |
| 28 | |
| 29 | macro_rules! point_op { |
| 30 | ($op:tt, $trait:ident($fn:ident), $trait_assign:ident($fn_assign:ident), $rhs:ident = $Rhs:ty => $x:expr, $y:expr) => { |
| 31 | impl<T: $trait<Output = T>> $trait<$Rhs> for Point2D<T> { |
| 32 | type Output = Self; |
| 33 | |
| 34 | fn $fn(self, $rhs: $Rhs) -> Self { |
| 35 | Self { |
| 36 | x: self.x $op $x, |
| 37 | y: self.y $op $y, |
| 38 | } |
| 39 | } |
| 40 | } |
| 41 | |
| 42 | impl<T: $trait<Output = T> + Copy> $trait_assign<$Rhs> for Point2D<T> { |
| 43 | fn $fn_assign(&mut self, $rhs: $Rhs) { |
| 44 | *self = Self { |
| 45 | x: self.x $op $x, |
| 46 | y: self.y $op $y, |
| 47 | } |
| 48 | } |
| 49 | } |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | point_op!(+, Add(add), AddAssign(add_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 54 | point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 55 | point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 56 | point_op!(/, Div(div), DivAssign(div_assign), rhs = Point2D<T> => rhs.x, rhs.y); |
| 57 | point_op!(+, Add(add), AddAssign(add_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 58 | point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 59 | point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 60 | point_op!(/, Div(div), DivAssign(div_assign), rhs = (T, T) => rhs.0, rhs.1); |
| 61 | |
| 62 | ////////// multiply point with scalar ////////////////////////////////////////// |
| 63 | impl<T: Mul<Output = T> + Copy> Mul<T> for Point2D<T> { |
| 64 | type Output = Self; |
| 65 | |
| 66 | fn mul(self, rhs: T) -> Self { |
| 67 | Self { |
| 68 | x: self.x * rhs, |
| 69 | y: self.y * rhs, |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | impl<T: Mul<Output = T> + Copy> MulAssign<T> for Point2D<T> { |
| 75 | fn mul_assign(&mut self, rhs: T) { |
| 76 | *self = Self { |
| 77 | x: self.x * rhs, |
| 78 | y: self.y * rhs, |
| 79 | } |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | ////////// divide point with scalar //////////////////////////////////////////// |
| 84 | impl<T: Div<Output = T> + Copy> Div<T> for Point2D<T> { |
| 85 | type Output = Self; |
| 86 | |
| 87 | fn div(self, rhs: T) -> Self { |
| 88 | Self { |
| 89 | x: self.x / rhs, |
| 90 | y: self.y / rhs, |
| 91 | } |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | impl<T: Div<Output = T> + Copy> DivAssign<T> for Point2D<T> { |
| 96 | fn div_assign(&mut self, rhs: T) { |
| 97 | *self = Self { |
| 98 | x: self.x / rhs, |
| 99 | y: self.y / rhs, |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | impl<T: Neg<Output = T>> Neg for Point2D<T> { |
| 105 | type Output = Self; |
| 106 | |
| 107 | fn neg(self) -> Self { |
| 108 | Self { |
| 109 | x: -self.x, |
| 110 | y: -self.y, |
| 111 | } |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | impl<T> From<(T, T)> for Point2D<T> { |
| 116 | fn from(item: (T, T)) -> Self { |
| 117 | Point2D { |
| 118 | x: item.0, |
| 119 | y: item.1, |
| 120 | } |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | impl<T> From<Point2D<T>> for (T, T) { |
| 125 | fn from(item: Point2D<T>) -> Self { |
| 126 | (item.x, item.y) |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | impl From<Degrees> for Point2D<f64> { |
| 131 | fn from(item: Degrees) -> Self { |
| 132 | Point2D { |
| 133 | x: (item.0 * std::f64::consts::PI / 180.0).cos(), |
| 134 | y: (item.0 * std::f64::consts::PI / 180.0).sin(), |
| 135 | } |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | impl From<Radians> for Point2D<f64> { |
| 140 | fn from(item: Radians) -> Self { |
| 141 | Point2D { |
| 142 | x: item.0.cos(), |
| 143 | y: item.0.sin(), |
| 144 | } |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | #[derive(Debug, Default, PartialEq, Clone, Copy)] |
| 149 | pub struct Degrees(pub f64); |
| 150 | #[derive(Debug, Default, PartialEq, Clone, Copy)] |
| 151 | pub struct Radians(pub f64); |
| 152 | |
| 153 | impl Degrees { |
| 154 | #[allow(dead_code)] |
| 155 | fn to_radians(&self) -> Radians { |
| 156 | Radians(self.0 * std::f64::consts::PI / 180.0) |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | impl Radians { |
| 161 | #[allow(dead_code)] |
| 162 | fn to_degrees(&self) -> Degrees { |
| 163 | Degrees(self.0 * 180.0 * std::f64::consts::FRAC_1_PI) |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | #[macro_export] |
| 168 | macro_rules! rect { |
| 169 | ( $x:expr, $y:expr ) => { |
| 170 | Rect { x: $x, y: $y } |
| 171 | }; |
| 172 | } |
| 173 | |
| 174 | #[derive(Default)] |
| 175 | pub struct Rect<T> { |
| 176 | pub width: T, |
| 177 | pub height: T, |
| 178 | } |
| 179 | |
| 180 | impl<T: Mul<Output = T> + Copy> Rect<T> { |
| 181 | #[allow(dead_code)] |
| 182 | pub fn area(&self) -> T { |
| 183 | self.width * self.height |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | impl<T> From<(T, T)> for Rect<T> { |
| 188 | fn from(item: (T, T)) -> Self { |
| 189 | Rect { |
| 190 | width: item.0, |
| 191 | height: item.1, |
| 192 | } |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | #[macro_export] |
| 197 | macro_rules! hashmap { |
| 198 | ($($k:expr => $v:expr),*) => { |
| 199 | { |
| 200 | let mut map = std::collections::HashMap::new(); |
| 201 | $(map.insert($k, $v);)* |
| 202 | map |
| 203 | } |
| 204 | } |
| 205 | } |
| 206 | |
| 207 | #[cfg(test)] |
| 208 | mod tests { |
| 209 | use super::*; |
| 210 | |
| 211 | #[test] |
| 212 | fn immutable_copy_of_point() { |
| 213 | let a = point!(0, 0); |
| 214 | let mut b = a; // Copy |
| 215 | assert_eq!(a, b); // PartialEq |
| 216 | b.x = 1; |
| 217 | assert_ne!(a, b); // PartialEq |
| 218 | } |
| 219 | |
| 220 | #[test] |
| 221 | fn add_points() { |
| 222 | let mut a = point!(1, 0); |
| 223 | assert_eq!(a + point!(2, 2), point!(3, 2)); // Add |
| 224 | a += point!(2, 2); // AddAssign |
| 225 | assert_eq!(a, point!(3, 2)); |
| 226 | assert_eq!(point!(1, 0) + (2, 3), point!(3, 3)); |
| 227 | } |
| 228 | |
| 229 | #[test] |
| 230 | fn sub_points() { |
| 231 | let mut a = point!(1, 0); |
| 232 | assert_eq!(a - point!(2, 2), point!(-1, -2)); |
| 233 | a -= point!(2, 2); |
| 234 | assert_eq!(a, point!(-1, -2)); |
| 235 | assert_eq!(point!(1, 0) - (2, 3), point!(-1, -3)); |
| 236 | } |
| 237 | |
| 238 | #[test] |
| 239 | fn mul_points() { |
| 240 | let mut a = point!(1, 2); |
| 241 | assert_eq!(a * 2, point!(2, 4)); |
| 242 | assert_eq!(a * point!(2, 3), point!(2, 6)); |
| 243 | a *= 2; |
| 244 | assert_eq!(a, point!(2, 4)); |
| 245 | a *= point!(3, 1); |
| 246 | assert_eq!(a, point!(6, 4)); |
| 247 | assert_eq!(point!(1, 0) * (2, 3), point!(2, 0)); |
| 248 | } |
| 249 | |
| 250 | #[test] |
| 251 | fn div_points() { |
| 252 | let mut a = point!(4, 8); |
| 253 | assert_eq!(a / 2, point!(2, 4)); |
| 254 | assert_eq!(a / point!(2, 4), point!(2, 2)); |
| 255 | a /= 2; |
| 256 | assert_eq!(a, point!(2, 4)); |
| 257 | a /= point!(2, 4); |
| 258 | assert_eq!(a, point!(1, 1)); |
| 259 | assert_eq!(point!(6, 3) / (2, 3), point!(3, 1)); |
| 260 | } |
| 261 | |
| 262 | #[test] |
| 263 | fn neg_point() { |
| 264 | assert_eq!(point!(1, 1), -point!(-1, -1)); |
| 265 | } |
| 266 | |
| 267 | #[test] |
| 268 | fn angles() { |
| 269 | assert_eq!(Radians(0.0).to_degrees(), Degrees(0.0)); |
| 270 | assert_eq!(Radians(std::f64::consts::PI).to_degrees(), Degrees(180.0)); |
| 271 | assert_eq!(Degrees(180.0).to_radians(), Radians(std::f64::consts::PI)); |
| 272 | assert!((Point2D::from(Degrees(90.0)) - point!(0.0, 1.0)).length() < 0.001); |
| 273 | assert!((Point2D::from(Radians(std::f64::consts::FRAC_PI_2)) - point!(0.0, 1.0)).length() < 0.001); |
| 274 | } |
| 275 | |
| 276 | #[test] |
| 277 | fn area_for_rect_of_multipliable_type() { |
| 278 | let r: Rect<_> = (30, 20).into(); // the Into trait uses the From trait |
| 279 | assert_eq!(r.area(), 30 * 20); |
| 280 | // let a = Rect::from(("a".to_string(), "b".to_string())).area(); // this doesn't work, because area() is not implemented for String |
| 281 | } |
| 282 | } |