bevy/examples/app/plugin.rs
Chris Janaqi ab407aa697 ♻️ Timer refactor to duration. Add Stopwatch struct. (#1151)
This pull request is following the discussion on the issue #1127. Additionally, it integrates the change proposed by #1112.

The list of change of this pull request:

*  Add `Timer::times_finished` method that counts the number of wraps for repeating timers.
* ♻️ Refactored `Timer`
* 🐛 Fix a bug where 2 successive calls to `Timer::tick` which makes a repeating timer to finish makes `Timer::just_finished` to return `false` where it should return `true`. Minimal failing example:
```rust
use bevy::prelude::*;
let mut timer: Timer<()> = Timer::from_seconds(1.0, true);
timer.tick(1.5);
assert!(timer.finished());
assert!(timer.just_finished());
timer.tick(1.5);
assert!(timer.finished());
assert!(timer.just_finished()); // <- This fails where it should not
```
* 📚 Add extensive documentation for Timer with doc examples.
*  Add a `Stopwatch` struct similar to `Timer` with extensive doc and tests.

Even if the type specialization is not retained for bevy, the doc, bugfix and added method are worth salvaging 😅.
This is my first PR for bevy, please be kind to me ❤️ .

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-03-05 19:59:14 +00:00

45 lines
1.4 KiB
Rust

use bevy::{prelude::*, utils::Duration};
/// Plugins are the foundation of Bevy. They are scoped sets of components, resources, and systems
/// that provide a specific piece of functionality (generally the smaller the scope, the better).
/// This example illustrates how to create a simple plugin that prints out a message.
fn main() {
App::build()
.add_plugins(DefaultPlugins)
// plugins are registered as part of the "app building" process
.add_plugin(PrintMessagePlugin {
wait_duration: Duration::from_secs(1),
message: "This is an example plugin".to_string(),
})
.run();
}
// This "print message plugin" prints a `message` every `wait_duration`
pub struct PrintMessagePlugin {
// Put your plugin configuration here
wait_duration: Duration,
message: String,
}
impl Plugin for PrintMessagePlugin {
// this is where we set up our plugin
fn build(&self, app: &mut AppBuilder) {
let state = PrintMessageState {
message: self.message.clone(),
timer: Timer::new(self.wait_duration, true),
};
app.insert_resource(state)
.add_system(print_message_system.system());
}
}
struct PrintMessageState {
message: String,
timer: Timer,
}
fn print_message_system(mut state: ResMut<PrintMessageState>, time: Res<Time>) {
if state.timer.tick(time.delta()).finished() {
println!("{}", state.message);
}
}