Merge pull request #325 from hecrj/feature/canvas-interaction

Canvas interactivity and Game of Life example

Cargo.toml

@@ -46,6 +46,7 @@ members = [
     "examples/custom_widget",
     "examples/download_progress",
     "examples/events",
+    "examples/game_of_life",
     "examples/geometry",
     "examples/integration",
     "examples/pane_grid",

core/src/keyboard.rs

@@ -1,6 +1,8 @@
 //! Reuse basic keyboard types.
+mod event;
 mod key_code;
 mod modifiers_state;
 
+pub use event::Event;
 pub use key_code::KeyCode;
 pub use modifiers_state::ModifiersState;

native/src/input/keyboard/event.rs → core/src/keyboard/event.rs

@@ -1,5 +1,4 @@
 use super::{KeyCode, ModifiersState};
-use crate::input::ButtonState;
 
 /// A keyboard event.
 ///
@@ -9,11 +8,17 @@ use crate::input::ButtonState;
 /// [open an issue]: https://github.com/hecrj/iced/issues
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub enum Event {
-    /// A keyboard key was pressed or released.
-    Input {
-        /// The state of the key
-        state: ButtonState,
+    /// A keyboard key was pressed.
+    KeyPressed {
+        /// The key identifier
+        key_code: KeyCode,
+
+        /// The state of the modifier keys
+        modifiers: ModifiersState,
+    },
 
+    /// A keyboard key was released.
+    KeyReleased {
         /// The key identifier
         key_code: KeyCode,
 

core/src/lib.rs

@@ -15,6 +15,7 @@
 #![forbid(unsafe_code)]
 #![forbid(rust_2018_idioms)]
 pub mod keyboard;
+pub mod mouse;
 
 mod align;
 mod background;

native/src/input/mouse.rs → core/src/mouse.rs

@@ -1,9 +1,8 @@
-//! Build mouse events.
+//! Reuse basic mouse types.
 mod button;
 mod event;
-
-pub mod click;
+mod interaction;
 
 pub use button::Button;
-pub use click::Click;
 pub use event::{Event, ScrollDelta};
+pub use interaction::Interaction;

native/src/input/mouse/event.rs → core/src/mouse/event.rs

@@ -1,5 +1,4 @@
 use super::Button;
-use crate::input::ButtonState;
 
 /// A mouse event.
 ///
@@ -24,14 +23,11 @@ pub enum Event {
         y: f32,
     },
 
-    /// A mouse button was pressed or released.
-    Input {
-        /// The state of the button
-        state: ButtonState,
+    /// A mouse button was pressed.
+    ButtonPressed(Button),
 
-        /// The button identifier
-        button: Button,
-    },
+    /// A mouse button was released.
+    ButtonReleased(Button),
 
     /// The mouse wheel was scrolled.
     WheelScrolled {

core/src/mouse/interaction.rs

@@ -0,0 +1,20 @@
+/// The interaction of a mouse cursor.
+#[derive(Debug, Eq, PartialEq, Clone, Copy, PartialOrd, Ord)]
+#[allow(missing_docs)]
+pub enum Interaction {
+    Idle,
+    Pointer,
+    Grab,
+    Text,
+    Crosshair,
+    Working,
+    Grabbing,
+    ResizingHorizontally,
+    ResizingVertically,
+}
+
+impl Default for Interaction {
+    fn default() -> Interaction {
+        Interaction::Idle
+    }
+}

core/src/point.rs

@@ -1,7 +1,7 @@
 use crate::Vector;
 
 /// A 2D point.
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq, Default)]
 pub struct Point {
     /// The X coordinate.
     pub x: f32,
@@ -67,3 +67,11 @@ impl std::ops::Sub<Vector> for Point {
         }
     }
 }
+
+impl std::ops::Sub<Point> for Point {
+    type Output = Vector;
+
+    fn sub(self, point: Point) -> Vector {
+        Vector::new(self.x - point.x, self.y - point.y)
+    }
+}

core/src/rectangle.rs

@@ -1,4 +1,4 @@
-use crate::Point;
+use crate::{Point, Size, Vector};
 
 /// A rectangle.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
@@ -17,6 +17,35 @@ pub struct Rectangle<T = f32> {
 }
 
 impl Rectangle<f32> {
+    /// Creates a new [`Rectangle`] with its top-left corner in the given
+    /// [`Point`] and with the provided [`Size`].
+    ///
+    /// [`Rectangle`]: struct.Rectangle.html
+    /// [`Point`]: struct.Point.html
+    /// [`Size`]: struct.Size.html
+    pub fn new(top_left: Point, size: Size) -> Self {
+        Self {
+            x: top_left.x,
+            y: top_left.y,
+            width: size.width,
+            height: size.height,
+        }
+    }
+
+    /// Creates a new [`Rectangle`] with its top-left corner at the origin
+    /// and with the provided [`Size`].
+    ///
+    /// [`Rectangle`]: struct.Rectangle.html
+    /// [`Size`]: struct.Size.html
+    pub fn with_size(size: Size) -> Self {
+        Self {
+            x: 0.0,
+            y: 0.0,
+            width: size.width,
+            height: size.height,
+        }
+    }
+
     /// Returns the [`Point`] at the center of the [`Rectangle`].
     ///
     /// [`Point`]: struct.Point.html
@@ -43,6 +72,21 @@ impl Rectangle<f32> {
         self.y + self.height / 2.0
     }
 
+    /// Returns the position of the top left corner of the [`Rectangle`].
+    ///
+    /// [`Rectangle`]: struct.Rectangle.html
+    pub fn position(&self) -> Point {
+        Point::new(self.x, self.y)
+    }
+
+    /// Returns the [`Size`] of the [`Rectangle`].
+    ///
+    /// [`Size`]: struct.Size.html
+    /// [`Rectangle`]: struct.Rectangle.html
+    pub fn size(&self) -> Size {
+        Size::new(self.width, self.height)
+    }
+
     /// Returns true if the given [`Point`] is contained in the [`Rectangle`].
     ///
     /// [`Point`]: struct.Point.html
@@ -112,8 +156,23 @@ impl From<Rectangle<f32>> for Rectangle<u32> {
         Rectangle {
             x: rectangle.x as u32,
             y: rectangle.y as u32,
-            width: rectangle.width.ceil() as u32,
-            height: rectangle.height.ceil() as u32,
+            width: (rectangle.width + 0.5).round() as u32,
+            height: (rectangle.height + 0.5).round() as u32,
+        }
+    }
+}
+
+impl<T> std::ops::Add<Vector<T>> for Rectangle<T>
+where
+    T: std::ops::Add<Output = T>,
+{
+    type Output = Rectangle<T>;
+
+    fn add(self, translation: Vector<T>) -> Self {
+        Rectangle {
+            x: self.x + translation.x,
+            y: self.y + translation.y,
+            ..self
         }
     }
 }

core/src/size.rs

@@ -15,6 +15,11 @@ impl Size {
     /// [`Size`]: struct.Size.html
     pub const ZERO: Size = Size::new(0., 0.);
 
+    /// A [`Size`] with a width and height of 1 unit.
+    ///
+    /// [`Size`]: struct.Size.html
+    pub const UNIT: Size = Size::new(1., 1.);
+
     /// A [`Size`] with infinite width and height.
     ///
     /// [`Size`]: struct.Size.html

core/src/vector.rs

@@ -43,6 +43,17 @@ where
     }
 }
 
+impl<T> std::ops::Mul<T> for Vector<T>
+where
+    T: std::ops::Mul<Output = T> + Copy,
+{
+    type Output = Self;
+
+    fn mul(self, scale: T) -> Self {
+        Self::new(self.x * scale, self.y * scale)
+    }
+}
+
 impl<T> Default for Vector<T>
 where
     T: Default,

examples/README.md

@@ -50,6 +50,27 @@ We have not yet implemented a `LocalStorage` version of the auto-save feature. T
 
 [TodoMVC]: http://todomvc.com/
 
+## [Game of Life](game_of_life)
+An interactive version of the [Game of Life], invented by [John Horton Conway].
+
+It runs a simulation in a background thread while allowing interaction with a `Canvas` that displays an infinite grid with zooming, panning, and drawing support.
+
+The relevant code is located in the __[`main`](game_of_life/src/main.rs)__ file.
+
+<div align="center">
+  <a href="https://gfycat.com/briefaccurateaardvark">
+    <img src="https://thumbs.gfycat.com/BriefAccurateAardvark-size_restricted.gif">
+  </a>
+</div>
+
+You can run it with `cargo run`:
+```
+cargo run --package game_of_life
+```
+
+[Game of Life]: https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life
+[John Horton Conway]: https://en.wikipedia.org/wiki/John_Horton_Conway
+
 ## [Styling](styling)
 An example showcasing custom styling with a light and dark theme.
 
@@ -69,7 +90,7 @@ cargo run --package styling
 ## Extras
 A bunch of simpler examples exist:
 
-- [`bezier_tool`](bezier_tool), a Paint-like tool for drawing Bézier curves using [`lyon`].
+- [`bezier_tool`](bezier_tool), a Paint-like tool for drawing Bézier curves using the `Canvas` widget.
 - [`clock`](clock), an application that uses the `Canvas` widget to draw a clock and its hands to display the current time.
 - [`color_palette`](color_palette), a color palette generator based on a user-defined root color.
 - [`counter`](counter), the classic counter example explained in the [`README`](../README.md).

examples/bezier_tool/Cargo.toml

@@ -6,7 +6,4 @@ edition = "2018"
 publish = false
 
 [dependencies]
-iced = { path = "../.." }
-iced_native = { path = "../../native" }
-iced_wgpu = { path = "../../wgpu" }
-lyon = "0.15"
+iced = { path = "../..", features = ["canvas"] }

examples/bezier_tool/README.md

@@ -1,6 +1,6 @@
 ## Bézier tool
 
-A Paint-like tool for drawing Bézier curves using [`lyon`].
+A Paint-like tool for drawing Bézier curves using the `Canvas` widget.
 
 The __[`main`]__ file contains all the code of the example.
 
@@ -16,4 +16,3 @@ cargo run --package bezier_tool
 ```
 
 [`main`]: src/main.rs
-[`lyon`]: https://github.com/nical/lyon