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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351
use radians::{self, Radians}; use turtle_window::TurtleWindow; use event::MouseButton; use {Speed, Color, Event}; #[derive(Debug, Clone, Copy, PartialEq, Eq)] enum AngleUnit { Degrees, Radians, } impl AngleUnit { fn to_radians(&self, angle: Angle) -> Radians { match *self { AngleUnit::Degrees => Radians::from_degrees_value(angle), AngleUnit::Radians => Radians::from_radians_value(angle), } } fn to_angle(&self, angle: Radians) -> Angle { match *self { AngleUnit::Degrees => angle.to_degrees(), AngleUnit::Radians => angle.to_radians(), } } } /// A point in 2D space: [x, y] /// /// ```rust /// # extern crate turtle; /// # use turtle::Point; /// # fn main() { /// let p: Point = [100., 120.]; /// // get x coordinate /// let x = p[0]; /// assert_eq!(x, 100.); /// // get y coordinate /// let y = p[1]; /// assert_eq!(y, 120.); /// # } pub type Point = [f64; 2]; /// Any distance value pub type Distance = f64; /// An angle value without a unit /// /// The unit of the angle represented by this value depends on what /// unit the Turtle was set to when this angle was retrieved pub type Angle = f64; /// A turtle with a pen attached to its tail pub struct Turtle { window: TurtleWindow, angle_unit: AngleUnit, } impl Turtle { /// Initialize a new Turtle instance pub fn new() -> Turtle { Turtle { window: TurtleWindow::new(), angle_unit: AngleUnit::Degrees, } } /// Returns the current speed of the turtle pub fn speed(&self) -> Speed { self.window.turtle().speed } /// Returns the turtle's current location (x, y) pub fn position(&self) -> Point { self.window.turtle().position } /// Returns the turtle's current heading /// /// Units are by default degrees, but can be set using the methods /// [`Turtle::use_degrees`](struct.Turtle.html#method.use_degrees) or /// [`Turtle::use_radians`](struct.Turtle.html#method.use_radians). pub fn heading(&self) -> Angle { let heading = self.window.turtle().heading; self.angle_unit.to_angle(heading) } /// Returns true if the turtle is visible pub fn is_visible(&self) -> bool { self.window.turtle().visible } /// Returns true if Angle values will be interpreted as degrees pub fn is_using_degrees(&self) -> bool { self.angle_unit == AngleUnit::Degrees } /// Returns true if Angle values will be interpreted as radians pub fn is_using_radians(&self) -> bool { self.angle_unit == AngleUnit::Radians } /// Return true if pen is down, false if it’s up. pub fn is_pen_down(&self) -> bool { self.window.drawing().pen.enabled } /// Returns the size (thickness) of the pen pub fn pen_size(&self) -> f64 { self.window.drawing().pen.thickness } /// Returns the color of the pen pub fn pen_color(&self) -> Color { self.window.drawing().pen.color } /// Returns the color of the background pub fn background_color(&self) -> Color { self.window.drawing().background } /// Returns the current fill color /// /// This will be used to fill the shape when `begin_fill()` and `end_fill()` are called. //TODO: Hyperlink begin_fill() and end_fill() methods to their docs pub fn fill_color(&self) -> Color { self.window.drawing().fill_color } /// Begin filling the shape drawn by the turtle's movements pub fn begin_fill(&mut self) { self.window.begin_fill(); } /// Stop filling the shape drawn by the turtle's movements pub fn end_fill(&mut self) { self.window.end_fill(); } /// Pull the pen down so that the turtle draws while moving pub fn pen_down(&mut self) { self.window.drawing_mut().pen.enabled = true; } /// Pick the pen up so that the turtle does not draw while moving pub fn pen_up(&mut self) { self.window.drawing_mut().pen.enabled = false; } /// Sets the thickness of the pen to the given size //TODO: Document this more like set_speed pub fn set_pen_size(&mut self, thickness: f64) { self.window.drawing_mut().pen.thickness = thickness; } /// Sets the color of the pen to the given color //TODO: Document this more like set_speed pub fn set_pen_color<C: Into<Color>>(&mut self, color: C) { self.window.drawing_mut().pen.color = color.into(); } /// Sets the color of the background to the given color //TODO: Document this more like set_speed pub fn set_background_color<C: Into<Color>>(&mut self, color: C) { self.window.drawing_mut().background = color.into(); } /// Sets the fill color to the given color /// /// **Note:** Only the fill color set **before** `begin_fill()` is called will be used to fill /// the shape. //TODO: Document this more like set_speed pub fn set_fill_color<C: Into<Color>>(&mut self, color: C) { self.window.drawing_mut().fill_color = color.into(); } /// Set the turtle's movement speed to the given setting. This speed affects the animation of /// the turtle's movement and rotation. /// /// This method's types make it so that it can be called in a number of different ways: /// /// ```rust,no_run /// # extern crate turtle; /// # use turtle::*; /// # fn main() { /// # let mut turtle = Turtle::new(); /// turtle.set_speed("normal"); /// turtle.set_speed("fast"); /// turtle.set_speed(2); /// turtle.set_speed(10); /// // Directly using a Speed variant works, but the methods above are usually more convenient. /// turtle.set_speed(Speed::Six); /// # } /// ``` /// /// If input is a number greater than 10 or smaller than 1, /// speed is set to 0 (`Speed::Instant`). Strings are converted as follows: /// /// | String | Value | /// | ----------- | -------------- | /// | `"slowest"` | `Speed::One` | /// | `"slow"` | `Speed::Three` | /// | `"normal"` | `Speed::Six` | /// | `"fast"` | `Speed::Eight` | /// | `"fastest"` | `Speed::Ten` | /// | `"instant"` | `Speed::Instant` | /// /// Anything else will cause the program to `panic!` at runtime. /// /// ## Moving Instantly /// /// A speed of zero (`Speed::Instant`) results in no animation. The turtle moves instantly /// and turns instantly. This is very useful for moving the turtle from its "home" position /// before you start drawing. By setting the speed to instant, you don't have to wait for /// the turtle to move into position. /// /// ## Learning About Conversion Traits /// /// Using this method is an excellent way to learn about conversion /// traits `From` and `Into`. This method takes a *generic type* as its speed parameter. That type /// is specified to implement the `Into` trait for the type `Speed`. That means that *any* type /// that can be converted into a `Speed` can be passed to this method. /// /// We have implemented that trait for several types like strings and 32-bit integers so that /// those values can be passed into this method. /// Rather than calling this function and passing `Speed::Six` directly, you can use just `6`. /// Rust will then allow us to call `.into()` as provided by the `Into<Speed>` trait to get the /// corresponding `Speed` value. /// /// You can pass in strings, 32-bit integers, and even `Speed` enum variants because they all /// implement the `Into<Speed>` trait. pub fn set_speed<S: Into<Speed>>(&mut self, speed: S) { self.window.turtle_mut().speed = speed.into(); } /// Makes the turtle invisible. The shell will not be shown, but drawings will continue. /// /// Useful for some complex drawings. pub fn hide(&mut self) { self.window.turtle_mut().visible = false; } /// Makes the turtle visible. pub fn show(&mut self) { self.window.turtle_mut().visible = true; } /// Change the angle unit to degrees. pub fn use_degrees(&mut self) { self.angle_unit = AngleUnit::Degrees; } /// Change the angle unit to radians. pub fn use_radians(&mut self) { self.angle_unit = AngleUnit::Radians; } /// Move the turtle forward by the given amount of `distance`. /// /// `distance` is given in "pixels" which are like really small turtle steps. /// `distance` can be negative in which case the turtle can move backward /// using this method. pub fn forward(&mut self, distance: Distance) { self.window.forward(distance); } /// Move the turtle backward by the given amount of `distance`. /// /// `distance` is given in "pixels" which are like really small turtle steps. /// `distance` can be negative in which case the turtle can move forwards /// using this method. pub fn backward(&mut self, distance: Distance) { // Moving backwards is essentially moving forwards with a negative distance self.window.forward(-distance); } /// Rotate the turtle right (clockwise) by the given angle. /// /// Units are by default degrees, but can be set using the methods /// [`Turtle::use_degrees`](struct.Turtle.html#method.use_degrees) or /// [`Turtle::use_radians`](struct.Turtle.html#method.use_radians). pub fn right(&mut self, angle: Angle) { let angle = self.angle_unit.to_radians(angle); self.window.rotate(angle, true); } /// Rotate the turtle left (counterclockwise) by the given angle. /// /// Units are by default degrees, but can be set using the methods /// [`Turtle::use_degrees`](struct.Turtle.html#method.use_degrees) or /// [`Turtle::use_radians`](struct.Turtle.html#method.use_radians). pub fn left(&mut self, angle: Angle) { let angle = self.angle_unit.to_radians(angle); self.window.rotate(angle, false); } /// Rotates the turtle to face the given coordinates. /// Coordinates are relative to the center of the window. /// /// If the coordinates are the same as the turtle's current position, no rotation takes place. /// Always rotates the least amount necessary in order to face the given point. /// /// ## UNSTABLE /// This feature is currently unstable and completely buggy. Do not use it until it is fixed. pub fn turn_towards(&mut self, target: Point) { let target_x = target[0]; let target_y = target[1]; let position = self.position(); let x = position[0]; let y = position[1]; if (target_x - x).abs() < 0.1 && (target_y - y).abs() < 0.1 { return; } let heading = self.window.turtle().heading; let angle = (target_y - y).atan2(target_x - x); let angle = Radians::from_radians_value(angle); let angle = (angle - heading) % radians::TWO_PI; // Try to rotate as little as possible let angle = if angle.abs() > radians::PI { // Using signum to deal with negative angles properly angle.signum()*(radians::TWO_PI - angle.abs()) } else { angle }; self.window.rotate(angle, false); } /// Returns the next event (if any). //TODO: Example of usage with an event loop pub fn poll_event(&mut self) -> Option<Event> { self.window.poll_event() } /// Convenience function that waits for a click to occur before returning. /// /// Useful for when you want your program to wait for the user to click before continuing so /// that it doesn't start right away. pub fn wait_for_click(&mut self) { loop { if let Some(Event::MouseButtonReleased(MouseButton::Left)) = self.poll_event() { break; } } } }