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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use std::sync::RwLock;
// A point in two-dimensional space.
#[derive(Debug, Clone)]
pub struct Point {
x: f64,
y: f64,
}
// A magnitude and direction in two-dimensional space.
// For simplicity we represent this as a point relative to the origin.
#[derive(Debug, Clone)]
pub struct Vector {
dx: f64,
dy: f64,
}
// Move from the given Point, according to the given Vector.
pub fn translate(p: &Point, v: Vector) -> Point {
Point {
x: p.x + v.dx,
y: p.y + v.dy,
}
}
// An entity in our imaginary world, which occupies a position in space
// and which can move about over time.
#[derive(Debug)]
pub struct Sprite {
// We must use interior mutability for managing mutable state, hence the `RwLock`.
current_position: RwLock<Point>,
}
impl Sprite {
fn new(initial_position: Option<Point>) -> Sprite {
Sprite {
current_position: RwLock::new(initial_position.unwrap_or(Point { x: 0.0, y: 0.0 })),
}
}
fn new_relative_to(reference: Point, direction: Vector) -> Sprite {
Sprite {
current_position: RwLock::new(translate(&reference, direction)),
}
}
fn get_position(&self) -> Point {
self.current_position.read().unwrap().clone()
}
fn move_to(&self, position: Point) {
*self.current_position.write().unwrap() = position;
}
fn move_by(&self, direction: Vector) {
let mut current_position = self.current_position.write().unwrap();
*current_position = translate(¤t_position, direction)
}
}
uniffi::include_scaffolding!("sprites");
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