dea91e94d6
# Objective In https://github.com/bevyengine/bevy/pull/6503 there were two changes to the top level tracing span "frame. Firstly it was renamed to "main app" and secondly the scope was reduced to *only* the main app. This means that there is no longer a top level span that can be used to compare frame times. In addition to making it easier to compare across versions again, it also helps when running without the render feature. Previously the "frame" span was present in both cases but now to compare "headless" and render the comparison is between "main app" and "winit event_handler" and Tracy doesn't handle comparing non-matching frames well. Before (0.9)  After (0.10)  ## Solution This PR reintroduces the "frame" span so comparisons across versions and features is again easy.   ### Alternative As an alternative route, the `tracy-client` crate that is used by `tracing-tracy` supports the ability to set multiple "Frame" markers using the `secondary_mark_frame` function. It may be possible to create a PR for `tracing-tracy` that exposes that functionality and then publish an "update" frame marker instead. This might have additional benefits in the future as it could be used for other systems we might want to track as frames without endless nesting.
1042 lines
36 KiB
Rust
1042 lines
36 KiB
Rust
use crate::{
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First, Main, MainSchedulePlugin, Plugin, PluginGroup, Startup, StateTransition, Update,
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};
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pub use bevy_derive::AppLabel;
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use bevy_ecs::{
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prelude::*,
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schedule::{
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apply_state_transition, common_conditions::run_once as run_once_condition,
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run_enter_schedule, BoxedScheduleLabel, IntoSystemConfigs, IntoSystemSetConfigs,
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ScheduleLabel,
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},
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};
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use bevy_utils::{tracing::debug, HashMap, HashSet};
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use std::{
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fmt::Debug,
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panic::{catch_unwind, resume_unwind, AssertUnwindSafe},
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};
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#[cfg(feature = "trace")]
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use bevy_utils::tracing::info_span;
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bevy_utils::define_label!(
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/// A strongly-typed class of labels used to identify an [`App`].
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AppLabel,
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/// A strongly-typed identifier for an [`AppLabel`].
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AppLabelId,
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);
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/// The [`Resource`] that stores the [`App`]'s [`TypeRegistry`](bevy_reflect::TypeRegistry).
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#[cfg(feature = "bevy_reflect")]
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#[derive(Resource, Clone, bevy_derive::Deref, bevy_derive::DerefMut, Default)]
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pub struct AppTypeRegistry(pub bevy_reflect::TypeRegistryArc);
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pub(crate) enum AppError {
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DuplicatePlugin { plugin_name: String },
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}
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#[allow(clippy::needless_doctest_main)]
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/// A container of app logic and data.
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///
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/// Bundles together the necessary elements like [`World`] and [`Schedule`] to create
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/// an ECS-based application. It also stores a pointer to a [runner function](Self::set_runner).
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/// The runner is responsible for managing the application's event loop and applying the
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/// [`Schedule`] to the [`World`] to drive application logic.
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///
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/// # Examples
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///
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/// Here is a simple "Hello World" Bevy app:
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///
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/// ```
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/// # use bevy_app::prelude::*;
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/// # use bevy_ecs::prelude::*;
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/// #
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/// fn main() {
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/// App::new()
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/// .add_systems(Update, hello_world_system)
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/// .run();
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/// }
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///
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/// fn hello_world_system() {
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/// println!("hello world");
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/// }
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/// ```
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pub struct App {
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/// The main ECS [`World`] of the [`App`].
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/// This stores and provides access to all the main data of the application.
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/// The systems of the [`App`] will run using this [`World`].
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/// If additional separate [`World`]-[`Schedule`] pairs are needed, you can use [`sub_app`](App::insert_sub_app)s.
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pub world: World,
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/// The [runner function](Self::set_runner) is primarily responsible for managing
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/// the application's event loop and advancing the [`Schedule`].
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/// Typically, it is not configured manually, but set by one of Bevy's built-in plugins.
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/// See `bevy::winit::WinitPlugin` and [`ScheduleRunnerPlugin`](crate::schedule_runner::ScheduleRunnerPlugin).
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pub runner: Box<dyn Fn(App) + Send>, // Send bound is required to make App Send
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/// The schedule that systems are added to by default.
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///
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/// The schedule that runs the main loop of schedule execution.
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///
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/// This is initially set to [`Main`].
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pub main_schedule_label: BoxedScheduleLabel,
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sub_apps: HashMap<AppLabelId, SubApp>,
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plugin_registry: Vec<Box<dyn Plugin>>,
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plugin_name_added: HashSet<String>,
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/// A private counter to prevent incorrect calls to `App::run()` from `Plugin::build()`
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building_plugin_depth: usize,
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}
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impl Debug for App {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(f, "App {{ sub_apps: ")?;
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f.debug_map()
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.entries(self.sub_apps.iter().map(|(k, v)| (k, v)))
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.finish()?;
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write!(f, "}}")
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}
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}
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/// A [`SubApp`] contains its own [`Schedule`] and [`World`] separate from the main [`App`].
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/// This is useful for situations where data and data processing should be kept completely separate
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/// from the main application. The primary use of this feature in bevy is to enable pipelined rendering.
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///
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/// # Example
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///
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/// ```rust
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/// # use bevy_app::{App, AppLabel, SubApp, Main};
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/// # use bevy_ecs::prelude::*;
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/// # use bevy_ecs::schedule::ScheduleLabel;
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///
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/// #[derive(Resource, Default)]
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/// struct Val(pub i32);
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///
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/// #[derive(Debug, Clone, Copy, Hash, PartialEq, Eq, AppLabel)]
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/// struct ExampleApp;
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///
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/// let mut app = App::new();
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///
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/// // initialize the main app with a value of 0;
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/// app.insert_resource(Val(10));
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///
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/// // create a app with a resource and a single schedule
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/// let mut sub_app = App::empty();
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/// // add an outer schedule that runs the main schedule
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/// sub_app.insert_resource(Val(100));
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///
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/// // initialize main schedule
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/// sub_app.add_systems(Main, |counter: Res<Val>| {
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/// // since we assigned the value from the main world in extract
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/// // we see that value instead of 100
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/// assert_eq!(counter.0, 10);
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/// });
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///
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/// // add the sub_app to the app
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/// app.insert_sub_app(ExampleApp, SubApp::new(sub_app, |main_world, sub_app| {
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/// // extract the value from the main app to the sub app
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/// sub_app.world.resource_mut::<Val>().0 = main_world.resource::<Val>().0;
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/// }));
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///
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/// // This will run the schedules once, since we're using the default runner
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/// app.run();
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/// ```
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pub struct SubApp {
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/// The [`SubApp`]'s instance of [`App`]
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pub app: App,
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/// A function that allows access to both the [`SubApp`] [`World`] and the main [`App`]. This is
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/// useful for moving data between the sub app and the main app.
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extract: Box<dyn Fn(&mut World, &mut App) + Send>,
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}
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impl SubApp {
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/// Creates a new [`SubApp`].
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///
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/// The provided function `extract` is normally called by the [`update`](App::update) method.
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/// After extract is called, the [`Schedule`] of the sub app is run. The [`World`]
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/// parameter represents the main app world, while the [`App`] parameter is just a mutable
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/// reference to the `SubApp` itself.
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pub fn new(app: App, extract: impl Fn(&mut World, &mut App) + Send + 'static) -> Self {
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Self {
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app,
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extract: Box::new(extract),
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}
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}
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/// Runs the [`SubApp`]'s default schedule.
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pub fn run(&mut self) {
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self.app.world.run_schedule(&*self.app.main_schedule_label);
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self.app.world.clear_trackers();
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}
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/// Extracts data from main world to this sub-app.
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pub fn extract(&mut self, main_world: &mut World) {
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(self.extract)(main_world, &mut self.app);
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}
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}
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impl Debug for SubApp {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(f, "SubApp {{ app: ")?;
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f.debug_map()
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.entries(self.app.sub_apps.iter().map(|(k, v)| (k, v)))
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.finish()?;
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write!(f, "}}")
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}
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}
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impl Default for App {
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fn default() -> Self {
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let mut app = App::empty();
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#[cfg(feature = "bevy_reflect")]
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app.init_resource::<AppTypeRegistry>();
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app.add_plugin(MainSchedulePlugin);
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app.add_event::<AppExit>();
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#[cfg(feature = "bevy_ci_testing")]
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{
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crate::ci_testing::setup_app(&mut app);
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}
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app
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}
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}
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impl App {
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/// Creates a new [`App`] with some default structure to enable core engine features.
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/// This is the preferred constructor for most use cases.
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pub fn new() -> App {
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App::default()
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}
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/// Creates a new empty [`App`] with minimal default configuration.
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///
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/// This constructor should be used if you wish to provide custom scheduling, exit handling, cleanup, etc.
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pub fn empty() -> App {
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let mut world = World::new();
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world.init_resource::<Schedules>();
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Self {
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world,
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runner: Box::new(run_once),
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sub_apps: HashMap::default(),
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plugin_registry: Vec::default(),
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plugin_name_added: Default::default(),
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main_schedule_label: Box::new(Main),
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building_plugin_depth: 0,
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}
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}
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/// Advances the execution of the [`Schedule`] by one cycle.
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///
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/// This method also updates sub apps.
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/// See [`insert_sub_app`](Self::insert_sub_app) for more details.
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///
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/// The schedule run by this method is determined by the [`main_schedule_label`](App) field.
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/// By default this is [`Main`].
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///
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/// # Panics
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///
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/// The active schedule of the app must be set before this method is called.
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pub fn update(&mut self) {
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#[cfg(feature = "trace")]
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let _bevy_update_span = info_span!("update").entered();
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{
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#[cfg(feature = "trace")]
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let _bevy_main_update_span = info_span!("main app").entered();
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self.world.run_schedule(&*self.main_schedule_label);
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}
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for (_label, sub_app) in self.sub_apps.iter_mut() {
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#[cfg(feature = "trace")]
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let _sub_app_span = info_span!("sub app", name = ?_label).entered();
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sub_app.extract(&mut self.world);
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sub_app.run();
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}
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self.world.clear_trackers();
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}
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/// Starts the application by calling the app's [runner function](Self::set_runner).
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///
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/// Finalizes the [`App`] configuration. For general usage, see the example on the item
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/// level documentation.
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///
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/// # `run()` might not return
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///
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/// Calls to [`App::run()`] might never return.
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///
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/// In simple and *headless* applications, one can expect that execution will
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/// proceed, normally, after calling [`run()`](App::run()) but this is not the case for
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/// windowed applications.
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///
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/// Windowed apps are typically driven by an *event loop* or *message loop* and
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/// some window-manager APIs expect programs to terminate when their primary
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/// window is closed and that event loop terminates – behavior of processes that
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/// do not is often platform dependent or undocumented.
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///
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/// By default, *Bevy* uses the `winit` crate for window creation. See
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/// [`WinitSettings::return_from_run`](https://docs.rs/bevy/latest/bevy/winit/struct.WinitSettings.html#structfield.return_from_run)
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/// for further discussion of this topic and for a mechanism to require that [`App::run()`]
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/// *does* return – albeit one that carries its own caveats and disclaimers.
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///
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/// # Panics
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///
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/// Panics if called from `Plugin::build()`, because it would prevent other plugins to properly build.
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pub fn run(&mut self) {
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#[cfg(feature = "trace")]
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let _bevy_app_run_span = info_span!("bevy_app").entered();
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let mut app = std::mem::replace(self, App::empty());
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if app.building_plugin_depth > 0 {
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panic!("App::run() was called from within Plugin::build(), which is not allowed.");
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}
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Self::setup(&mut app);
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let runner = std::mem::replace(&mut app.runner, Box::new(run_once));
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(runner)(app);
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}
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/// Run [`Plugin::setup`] for each plugin. This is usually called by [`App::run`], but can
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/// be useful for situations where you want to use [`App::update`].
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pub fn setup(&mut self) {
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// temporarily remove the plugin registry to run each plugin's setup function on app.
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let plugin_registry = std::mem::take(&mut self.plugin_registry);
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for plugin in &plugin_registry {
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plugin.setup(self);
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}
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self.plugin_registry = plugin_registry;
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}
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|
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/// Adds [`State<S>`] and [`NextState<S>`] resources, [`OnEnter`] and [`OnExit`] schedules
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/// for each state variant (if they don't already exist), an instance of [`apply_state_transition::<S>`] in
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/// [`StateTransition`] so that transitions happen before [`Update`] and
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/// a instance of [`run_enter_schedule::<S>`] in [`StateTransition`] with a
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/// [`run_once`](`run_once_condition`) condition to run the on enter schedule of the
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/// initial state.
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///
|
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/// If you would like to control how other systems run based on the current state,
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/// you can emulate this behavior using the [`in_state`] [`Condition`](bevy_ecs::schedule::Condition).
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///
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/// Note that you can also apply state transitions at other points in the schedule
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/// by adding the [`apply_state_transition`] system manually.
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pub fn add_state<S: States>(&mut self) -> &mut Self {
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self.init_resource::<State<S>>()
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.init_resource::<NextState<S>>()
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.add_systems(
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StateTransition,
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(
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run_enter_schedule::<S>.run_if(run_once_condition()),
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apply_state_transition::<S>,
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)
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.chain(),
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);
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|
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// The OnEnter, OnExit, and OnTransition schedules are lazily initialized
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// (i.e. when the first system is added to them), and World::try_run_schedule is used to fail
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// gracefully if they aren't present.
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|
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self
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}
|
||
|
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/// Adds a system to the default system set and schedule of the app's [`Schedules`].
|
||
///
|
||
/// Refer to the [system module documentation](bevy_ecs::system) to see how a system
|
||
/// can be defined.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// # fn my_system() {}
|
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/// # let mut app = App::new();
|
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/// #
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/// app.add_system(my_system);
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||
/// ```
|
||
#[deprecated(
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since = "0.11.0",
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note = "Please use `add_systems` instead. If you didn't change the default base set, you should use `add_systems(Update, your_system).`"
|
||
)]
|
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pub fn add_system<M>(&mut self, system: impl IntoSystemConfigs<M>) -> &mut Self {
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self.add_systems(Update, system)
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}
|
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|
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/// Adds a system to the given schedule in this app's [`Schedules`].
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// # let mut app = App::new();
|
||
/// # fn system_a() {}
|
||
/// # fn system_b() {}
|
||
/// # fn system_c() {}
|
||
/// # fn should_run() -> bool { true }
|
||
/// #
|
||
/// app.add_systems(Update, (system_a, system_b, system_c));
|
||
/// app.add_systems(Update, (system_a, system_b).run_if(should_run));
|
||
/// ```
|
||
pub fn add_systems<M>(
|
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&mut self,
|
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schedule: impl ScheduleLabel,
|
||
systems: impl IntoSystemConfigs<M>,
|
||
) -> &mut Self {
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||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
|
||
if let Some(schedule) = schedules.get_mut(&schedule) {
|
||
schedule.add_systems(systems);
|
||
} else {
|
||
let mut new_schedule = Schedule::new();
|
||
new_schedule.add_systems(systems);
|
||
schedules.insert(schedule, new_schedule);
|
||
}
|
||
|
||
self
|
||
}
|
||
|
||
/// Adds a system to [`Startup`].
|
||
///
|
||
/// These systems will run exactly once, at the start of the [`App`]'s lifecycle.
|
||
/// To add a system that runs every frame, see [`add_system`](Self::add_system).
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// fn my_startup_system(_commands: Commands) {
|
||
/// println!("My startup system");
|
||
/// }
|
||
///
|
||
/// App::new()
|
||
/// .add_systems(Startup, my_startup_system);
|
||
/// ```
|
||
#[deprecated(
|
||
since = "0.11.0",
|
||
note = "Please use `add_systems` instead. If you didn't change the default base set, you should use `add_systems(Startup, your_system).`"
|
||
)]
|
||
pub fn add_startup_system<M>(&mut self, system: impl IntoSystemConfigs<M>) -> &mut Self {
|
||
self.add_systems(Startup, system)
|
||
}
|
||
|
||
/// Adds a collection of systems to [`Startup`].
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// # let mut app = App::new();
|
||
/// # fn startup_system_a() {}
|
||
/// # fn startup_system_b() {}
|
||
/// # fn startup_system_c() {}
|
||
/// #
|
||
/// app.add_systems(Startup, (
|
||
/// startup_system_a,
|
||
/// startup_system_b,
|
||
/// startup_system_c,
|
||
/// ));
|
||
/// ```
|
||
#[deprecated(
|
||
since = "0.11.0",
|
||
note = "Please use `add_systems` instead. If you didn't change the default base set, you should use `add_systems(Startup, your_system).`"
|
||
)]
|
||
pub fn add_startup_systems<M>(&mut self, systems: impl IntoSystemConfigs<M>) -> &mut Self {
|
||
self.add_systems(Startup, systems.into_configs())
|
||
}
|
||
|
||
/// Configures a system set in the default schedule, adding the set if it does not exist.
|
||
pub fn configure_set(
|
||
&mut self,
|
||
schedule: impl ScheduleLabel,
|
||
set: impl IntoSystemSetConfig,
|
||
) -> &mut Self {
|
||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
if let Some(schedule) = schedules.get_mut(&schedule) {
|
||
schedule.configure_set(set);
|
||
} else {
|
||
let mut new_schedule = Schedule::new();
|
||
new_schedule.configure_set(set);
|
||
schedules.insert(schedule, new_schedule);
|
||
}
|
||
self
|
||
}
|
||
|
||
/// Configures a collection of system sets in the default schedule, adding any sets that do not exist.
|
||
pub fn configure_sets(
|
||
&mut self,
|
||
schedule: impl ScheduleLabel,
|
||
sets: impl IntoSystemSetConfigs,
|
||
) -> &mut Self {
|
||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
if let Some(schedule) = schedules.get_mut(&schedule) {
|
||
schedule.configure_sets(sets);
|
||
} else {
|
||
let mut new_schedule = Schedule::new();
|
||
new_schedule.configure_sets(sets);
|
||
schedules.insert(schedule, new_schedule);
|
||
}
|
||
self
|
||
}
|
||
|
||
/// Setup the application to manage events of type `T`.
|
||
///
|
||
/// This is done by adding a [`Resource`] of type [`Events::<T>`],
|
||
/// and inserting an [`update_system`](Events::update_system) into [`First`].
|
||
///
|
||
/// See [`Events`] for defining events.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// # struct MyEvent;
|
||
/// # let mut app = App::new();
|
||
/// #
|
||
/// app.add_event::<MyEvent>();
|
||
/// ```
|
||
pub fn add_event<T>(&mut self) -> &mut Self
|
||
where
|
||
T: Event,
|
||
{
|
||
if !self.world.contains_resource::<Events<T>>() {
|
||
self.init_resource::<Events<T>>()
|
||
.add_systems(First, Events::<T>::update_system);
|
||
}
|
||
self
|
||
}
|
||
|
||
/// Inserts a [`Resource`] to the current [`App`] and overwrites any [`Resource`] previously added of the same type.
|
||
///
|
||
/// A [`Resource`] in Bevy represents globally unique data. [`Resource`]s must be added to Bevy apps
|
||
/// before using them. This happens with [`insert_resource`](Self::insert_resource).
|
||
///
|
||
/// See [`init_resource`](Self::init_resource) for [`Resource`]s that implement [`Default`] or [`FromWorld`].
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// #[derive(Resource)]
|
||
/// struct MyCounter {
|
||
/// counter: usize,
|
||
/// }
|
||
///
|
||
/// App::new()
|
||
/// .insert_resource(MyCounter { counter: 0 });
|
||
/// ```
|
||
pub fn insert_resource<R: Resource>(&mut self, resource: R) -> &mut Self {
|
||
self.world.insert_resource(resource);
|
||
self
|
||
}
|
||
|
||
/// Inserts a non-send resource to the app.
|
||
///
|
||
/// You usually want to use [`insert_resource`](Self::insert_resource),
|
||
/// but there are some special cases when a resource cannot be sent across threads.
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// struct MyCounter {
|
||
/// counter: usize,
|
||
/// }
|
||
///
|
||
/// App::new()
|
||
/// .insert_non_send_resource(MyCounter { counter: 0 });
|
||
/// ```
|
||
pub fn insert_non_send_resource<R: 'static>(&mut self, resource: R) -> &mut Self {
|
||
self.world.insert_non_send_resource(resource);
|
||
self
|
||
}
|
||
|
||
/// Initialize a [`Resource`] with standard starting values by adding it to the [`World`].
|
||
///
|
||
/// If the [`Resource`] already exists, nothing happens.
|
||
///
|
||
/// The [`Resource`] must implement the [`FromWorld`] trait.
|
||
/// If the [`Default`] trait is implemented, the [`FromWorld`] trait will use
|
||
/// the [`Default::default`] method to initialize the [`Resource`].
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// # use bevy_ecs::prelude::*;
|
||
/// #
|
||
/// #[derive(Resource)]
|
||
/// struct MyCounter {
|
||
/// counter: usize,
|
||
/// }
|
||
///
|
||
/// impl Default for MyCounter {
|
||
/// fn default() -> MyCounter {
|
||
/// MyCounter {
|
||
/// counter: 100
|
||
/// }
|
||
/// }
|
||
/// }
|
||
///
|
||
/// App::new()
|
||
/// .init_resource::<MyCounter>();
|
||
/// ```
|
||
pub fn init_resource<R: Resource + FromWorld>(&mut self) -> &mut Self {
|
||
self.world.init_resource::<R>();
|
||
self
|
||
}
|
||
|
||
/// Initialize a non-send [`Resource`] with standard starting values by adding it to the [`World`].
|
||
///
|
||
/// The [`Resource`] must implement the [`FromWorld`] trait.
|
||
/// If the [`Default`] trait is implemented, the [`FromWorld`] trait will use
|
||
/// the [`Default::default`] method to initialize the [`Resource`].
|
||
pub fn init_non_send_resource<R: 'static + FromWorld>(&mut self) -> &mut Self {
|
||
self.world.init_non_send_resource::<R>();
|
||
self
|
||
}
|
||
|
||
/// Sets the function that will be called when the app is run.
|
||
///
|
||
/// The runner function `run_fn` is called only once by [`App::run`]. If the
|
||
/// presence of a main loop in the app is desired, it is the responsibility of the runner
|
||
/// function to provide it.
|
||
///
|
||
/// The runner function is usually not set manually, but by Bevy integrated plugins
|
||
/// (e.g. `WinitPlugin`).
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// #
|
||
/// fn my_runner(mut app: App) {
|
||
/// loop {
|
||
/// println!("In main loop");
|
||
/// app.update();
|
||
/// }
|
||
/// }
|
||
///
|
||
/// App::new()
|
||
/// .set_runner(my_runner);
|
||
/// ```
|
||
pub fn set_runner(&mut self, run_fn: impl Fn(App) + 'static + Send) -> &mut Self {
|
||
self.runner = Box::new(run_fn);
|
||
self
|
||
}
|
||
|
||
/// Adds a single [`Plugin`].
|
||
///
|
||
/// One of Bevy's core principles is modularity. All Bevy engine features are implemented
|
||
/// as [`Plugin`]s. This includes internal features like the renderer.
|
||
///
|
||
/// Bevy also provides a few sets of default [`Plugin`]s. See [`add_plugins`](Self::add_plugins).
|
||
///
|
||
/// # Examples
|
||
///
|
||
/// ```
|
||
/// # use bevy_app::prelude::*;
|
||
/// #
|
||
/// # // Dummies created to avoid using `bevy_log`,
|
||
/// # // which pulls in too many dependencies and breaks rust-analyzer
|
||
/// # pub mod bevy_log {
|
||
/// # use bevy_app::prelude::*;
|
||
/// # #[derive(Default)]
|
||
/// # pub struct LogPlugin;
|
||
/// # impl Plugin for LogPlugin{
|
||
/// # fn build(&self, app: &mut App) {}
|
||
/// # }
|
||
/// # }
|
||
/// App::new().add_plugin(bevy_log::LogPlugin::default());
|
||
/// ```
|
||
///
|
||
/// # Panics
|
||
///
|
||
/// Panics if the plugin was already added to the application.
|
||
pub fn add_plugin<T>(&mut self, plugin: T) -> &mut Self
|
||
where
|
||
T: Plugin,
|
||
{
|
||
match self.add_boxed_plugin(Box::new(plugin)) {
|
||
Ok(app) => app,
|
||
Err(AppError::DuplicatePlugin { plugin_name }) => panic!(
|
||
"Error adding plugin {plugin_name}: : plugin was already added in application"
|
||
),
|
||
}
|
||
}
|
||
|
||
/// Boxed variant of [`add_plugin`](App::add_plugin) that can be used from a [`PluginGroup`]
|
||
pub(crate) fn add_boxed_plugin(
|
||
&mut self,
|
||
plugin: Box<dyn Plugin>,
|
||
) -> Result<&mut Self, AppError> {
|
||
debug!("added plugin: {}", plugin.name());
|
||
if plugin.is_unique() && !self.plugin_name_added.insert(plugin.name().to_string()) {
|
||
Err(AppError::DuplicatePlugin {
|
||
plugin_name: plugin.name().to_string(),
|
||
})?;
|
||
}
|
||
self.building_plugin_depth += 1;
|
||
let result = catch_unwind(AssertUnwindSafe(|| plugin.build(self)));
|
||
self.building_plugin_depth -= 1;
|
||
if let Err(payload) = result {
|
||
resume_unwind(payload);
|
||
}
|
||
self.plugin_registry.push(plugin);
|
||
Ok(self)
|
||
}
|
||
|
||
/// Checks if a [`Plugin`] has already been added.
|
||
///
|
||
/// This can be used by plugins to check if a plugin they depend upon has already been
|
||
/// added.
|
||
pub fn is_plugin_added<T>(&self) -> bool
|
||
where
|
||
T: Plugin,
|
||
{
|
||
self.plugin_registry
|
||
.iter()
|
||
.any(|p| p.downcast_ref::<T>().is_some())
|
||
}
|
||
|
||
/// Returns a vector of references to any plugins of type `T` that have been added.
|
||
///
|
||
/// This can be used to read the settings of any already added plugins.
|
||
/// This vector will be length zero if no plugins of that type have been added.
|
||
/// If multiple copies of the same plugin are added to the [`App`], they will be listed in insertion order in this vector.
|
||
///
|
||
/// ```rust
|
||
/// # use bevy_app::prelude::*;
|
||
/// # #[derive(Default)]
|
||
/// # struct ImagePlugin {
|
||
/// # default_sampler: bool,
|
||
/// # }
|
||
/// # impl Plugin for ImagePlugin {
|
||
/// # fn build(&self, app: &mut App) {}
|
||
/// # }
|
||
/// # let mut app = App::new();
|
||
/// # app.add_plugin(ImagePlugin::default());
|
||
/// let default_sampler = app.get_added_plugins::<ImagePlugin>()[0].default_sampler;
|
||
/// ```
|
||
pub fn get_added_plugins<T>(&self) -> Vec<&T>
|
||
where
|
||
T: Plugin,
|
||
{
|
||
self.plugin_registry
|
||
.iter()
|
||
.filter_map(|p| p.downcast_ref())
|
||
.collect()
|
||
}
|
||
|
||
/// Adds a group of [`Plugin`]s.
|
||
///
|
||
/// [`Plugin`]s can be grouped into a set by using a [`PluginGroup`].
|
||
///
|
||
/// There are built-in [`PluginGroup`]s that provide core engine functionality.
|
||
/// The [`PluginGroup`]s available by default are `DefaultPlugins` and `MinimalPlugins`.
|
||
///
|
||
/// To customize the plugins in the group (reorder, disable a plugin, add a new plugin
|
||
/// before / after another plugin), call [`build()`](PluginGroup::build) on the group,
|
||
/// which will convert it to a [`PluginGroupBuilder`](crate::PluginGroupBuilder).
|
||
///
|
||
/// ## Examples
|
||
/// ```
|
||
/// # use bevy_app::{prelude::*, PluginGroupBuilder, NoopPluginGroup as MinimalPlugins};
|
||
/// #
|
||
/// App::new()
|
||
/// .add_plugins(MinimalPlugins);
|
||
/// ```
|
||
///
|
||
/// # Panics
|
||
///
|
||
/// Panics if one of the plugin in the group was already added to the application.
|
||
pub fn add_plugins<T: PluginGroup>(&mut self, group: T) -> &mut Self {
|
||
let builder = group.build();
|
||
builder.finish(self);
|
||
self
|
||
}
|
||
|
||
/// Registers the type `T` in the [`TypeRegistry`](bevy_reflect::TypeRegistry) resource,
|
||
/// adding reflect data as specified in the [`Reflect`](bevy_reflect::Reflect) derive:
|
||
/// ```rust,ignore
|
||
/// #[derive(Reflect)]
|
||
/// #[reflect(Component, Serialize, Deserialize)] // will register ReflectComponent, ReflectSerialize, ReflectDeserialize
|
||
/// ```
|
||
///
|
||
/// See [`bevy_reflect::TypeRegistry::register`].
|
||
#[cfg(feature = "bevy_reflect")]
|
||
pub fn register_type<T: bevy_reflect::GetTypeRegistration>(&mut self) -> &mut Self {
|
||
let registry = self.world.resource_mut::<AppTypeRegistry>();
|
||
registry.write().register::<T>();
|
||
self
|
||
}
|
||
|
||
/// Adds the type data `D` to type `T` in the [`TypeRegistry`](bevy_reflect::TypeRegistry) resource.
|
||
///
|
||
/// Most of the time [`App::register_type`] can be used instead to register a type you derived [`Reflect`](bevy_reflect::Reflect) for.
|
||
/// However, in cases where you want to add a piece of type data that was not included in the list of `#[reflect(...)]` type data in the derive,
|
||
/// or where the type is generic and cannot register e.g. `ReflectSerialize` unconditionally without knowing the specific type parameters,
|
||
/// this method can be used to insert additional type data.
|
||
///
|
||
/// # Example
|
||
/// ```rust
|
||
/// use bevy_app::App;
|
||
/// use bevy_reflect::{ReflectSerialize, ReflectDeserialize};
|
||
///
|
||
/// App::new()
|
||
/// .register_type::<Option<String>>()
|
||
/// .register_type_data::<Option<String>, ReflectSerialize>()
|
||
/// .register_type_data::<Option<String>, ReflectDeserialize>();
|
||
/// ```
|
||
///
|
||
/// See [`bevy_reflect::TypeRegistry::register_type_data`].
|
||
#[cfg(feature = "bevy_reflect")]
|
||
pub fn register_type_data<
|
||
T: bevy_reflect::Reflect + 'static,
|
||
D: bevy_reflect::TypeData + bevy_reflect::FromType<T>,
|
||
>(
|
||
&mut self,
|
||
) -> &mut Self {
|
||
let registry = self.world.resource_mut::<AppTypeRegistry>();
|
||
registry.write().register_type_data::<T, D>();
|
||
self
|
||
}
|
||
|
||
/// Retrieves a `SubApp` stored inside this [`App`].
|
||
///
|
||
/// # Panics
|
||
///
|
||
/// Panics if the `SubApp` doesn't exist.
|
||
pub fn sub_app_mut(&mut self, label: impl AppLabel) -> &mut App {
|
||
match self.get_sub_app_mut(label) {
|
||
Ok(app) => app,
|
||
Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_str()),
|
||
}
|
||
}
|
||
|
||
/// Retrieves a `SubApp` inside this [`App`] with the given label, if it exists. Otherwise returns
|
||
/// an [`Err`] containing the given label.
|
||
pub fn get_sub_app_mut(&mut self, label: impl AppLabel) -> Result<&mut App, AppLabelId> {
|
||
let label = label.as_label();
|
||
self.sub_apps
|
||
.get_mut(&label)
|
||
.map(|sub_app| &mut sub_app.app)
|
||
.ok_or(label)
|
||
}
|
||
|
||
/// Retrieves a `SubApp` stored inside this [`App`].
|
||
///
|
||
/// # Panics
|
||
///
|
||
/// Panics if the `SubApp` doesn't exist.
|
||
pub fn sub_app(&self, label: impl AppLabel) -> &App {
|
||
match self.get_sub_app(label) {
|
||
Ok(app) => app,
|
||
Err(label) => panic!("Sub-App with label '{:?}' does not exist", label.as_str()),
|
||
}
|
||
}
|
||
|
||
/// Inserts an existing sub app into the app
|
||
pub fn insert_sub_app(&mut self, label: impl AppLabel, sub_app: SubApp) {
|
||
self.sub_apps.insert(label.as_label(), sub_app);
|
||
}
|
||
|
||
/// Removes a sub app from the app. Returns [`None`] if the label doesn't exist.
|
||
pub fn remove_sub_app(&mut self, label: impl AppLabel) -> Option<SubApp> {
|
||
self.sub_apps.remove(&label.as_label())
|
||
}
|
||
|
||
/// Retrieves a `SubApp` inside this [`App`] with the given label, if it exists. Otherwise returns
|
||
/// an [`Err`] containing the given label.
|
||
pub fn get_sub_app(&self, label: impl AppLabel) -> Result<&App, impl AppLabel> {
|
||
self.sub_apps
|
||
.get(&label.as_label())
|
||
.map(|sub_app| &sub_app.app)
|
||
.ok_or(label)
|
||
}
|
||
|
||
/// Adds a new `schedule` to the [`App`] under the provided `label`.
|
||
///
|
||
/// # Warning
|
||
/// This method will overwrite any existing schedule at that label.
|
||
/// To avoid this behavior, use the `init_schedule` method instead.
|
||
pub fn add_schedule(&mut self, label: impl ScheduleLabel, schedule: Schedule) -> &mut Self {
|
||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
schedules.insert(label, schedule);
|
||
|
||
self
|
||
}
|
||
|
||
/// Initializes a new empty `schedule` to the [`App`] under the provided `label` if it does not exists.
|
||
///
|
||
/// See [`App::add_schedule`] to pass in a pre-constructed schedule.
|
||
pub fn init_schedule(&mut self, label: impl ScheduleLabel) -> &mut Self {
|
||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
if !schedules.contains(&label) {
|
||
schedules.insert(label, Schedule::new());
|
||
}
|
||
self
|
||
}
|
||
|
||
/// Gets read-only access to the [`Schedule`] with the provided `label` if it exists.
|
||
pub fn get_schedule(&self, label: impl ScheduleLabel) -> Option<&Schedule> {
|
||
let schedules = self.world.get_resource::<Schedules>()?;
|
||
schedules.get(&label)
|
||
}
|
||
|
||
/// Gets read-write access to a [`Schedule`] with the provided `label` if it exists.
|
||
pub fn get_schedule_mut(&mut self, label: impl ScheduleLabel) -> Option<&mut Schedule> {
|
||
let schedules = self.world.get_resource_mut::<Schedules>()?;
|
||
// We need to call .into_inner here to satisfy the borrow checker:
|
||
// it can reason about reborrows using ordinary references but not the `Mut` smart pointer.
|
||
schedules.into_inner().get_mut(&label)
|
||
}
|
||
|
||
/// Applies the function to the [`Schedule`] associated with `label`.
|
||
///
|
||
/// **Note:** This will create the schedule if it does not already exist.
|
||
pub fn edit_schedule(
|
||
&mut self,
|
||
label: impl ScheduleLabel,
|
||
mut f: impl FnMut(&mut Schedule),
|
||
) -> &mut Self {
|
||
let mut schedules = self.world.resource_mut::<Schedules>();
|
||
|
||
if schedules.get(&label).is_none() {
|
||
schedules.insert(label.dyn_clone(), Schedule::new());
|
||
}
|
||
|
||
let schedule = schedules.get_mut(&label).unwrap();
|
||
// Call the function f, passing in the schedule retrieved
|
||
f(schedule);
|
||
|
||
self
|
||
}
|
||
}
|
||
|
||
fn run_once(mut app: App) {
|
||
app.update();
|
||
}
|
||
|
||
/// An event that indicates the [`App`] should exit. This will fully exit the app process at the
|
||
/// start of the next tick of the schedule.
|
||
///
|
||
/// You can also use this event to detect that an exit was requested. In order to receive it, systems
|
||
/// subscribing to this event should run after it was emitted and before the schedule of the same
|
||
/// frame is over. This is important since [`App::run()`] might never return.
|
||
///
|
||
/// If you don't require access to other components or resources, consider implementing the [`Drop`]
|
||
/// trait on components/resources for code that runs on exit. That saves you from worrying about
|
||
/// system schedule ordering, and is idiomatic Rust.
|
||
#[derive(Debug, Clone, Default)]
|
||
pub struct AppExit;
|
||
|
||
#[cfg(test)]
|
||
mod tests {
|
||
use bevy_ecs::{
|
||
schedule::{OnEnter, States},
|
||
system::Commands,
|
||
};
|
||
|
||
use crate::{App, Plugin};
|
||
|
||
struct PluginA;
|
||
impl Plugin for PluginA {
|
||
fn build(&self, _app: &mut crate::App) {}
|
||
}
|
||
struct PluginB;
|
||
impl Plugin for PluginB {
|
||
fn build(&self, _app: &mut crate::App) {}
|
||
}
|
||
struct PluginC<T>(T);
|
||
impl<T: Send + Sync + 'static> Plugin for PluginC<T> {
|
||
fn build(&self, _app: &mut crate::App) {}
|
||
}
|
||
struct PluginD;
|
||
impl Plugin for PluginD {
|
||
fn build(&self, _app: &mut crate::App) {}
|
||
fn is_unique(&self) -> bool {
|
||
false
|
||
}
|
||
}
|
||
|
||
#[test]
|
||
fn can_add_two_plugins() {
|
||
App::new().add_plugin(PluginA).add_plugin(PluginB);
|
||
}
|
||
|
||
#[test]
|
||
#[should_panic]
|
||
fn cant_add_twice_the_same_plugin() {
|
||
App::new().add_plugin(PluginA).add_plugin(PluginA);
|
||
}
|
||
|
||
#[test]
|
||
fn can_add_twice_the_same_plugin_with_different_type_param() {
|
||
App::new().add_plugin(PluginC(0)).add_plugin(PluginC(true));
|
||
}
|
||
|
||
#[test]
|
||
fn can_add_twice_the_same_plugin_not_unique() {
|
||
App::new().add_plugin(PluginD).add_plugin(PluginD);
|
||
}
|
||
|
||
#[test]
|
||
#[should_panic]
|
||
fn cant_call_app_run_from_plugin_build() {
|
||
struct PluginRun;
|
||
struct InnerPlugin;
|
||
impl Plugin for InnerPlugin {
|
||
fn build(&self, _: &mut crate::App) {}
|
||
}
|
||
impl Plugin for PluginRun {
|
||
fn build(&self, app: &mut crate::App) {
|
||
app.add_plugin(InnerPlugin).run();
|
||
}
|
||
}
|
||
App::new().add_plugin(PluginRun);
|
||
}
|
||
|
||
#[derive(States, PartialEq, Eq, Debug, Default, Hash, Clone)]
|
||
enum AppState {
|
||
#[default]
|
||
MainMenu,
|
||
}
|
||
fn bar(mut commands: Commands) {
|
||
commands.spawn_empty();
|
||
}
|
||
|
||
fn foo(mut commands: Commands) {
|
||
commands.spawn_empty();
|
||
}
|
||
|
||
#[test]
|
||
fn add_systems_should_create_schedule_if_it_does_not_exist() {
|
||
let mut app = App::new();
|
||
app.add_state::<AppState>()
|
||
.add_systems(OnEnter(AppState::MainMenu), (foo, bar));
|
||
|
||
app.world.run_schedule(OnEnter(AppState::MainMenu));
|
||
assert_eq!(app.world.entities().len(), 2);
|
||
}
|
||
|
||
#[test]
|
||
fn add_systems_should_create_schedule_if_it_does_not_exist2() {
|
||
let mut app = App::new();
|
||
app.add_systems(OnEnter(AppState::MainMenu), (foo, bar))
|
||
.add_state::<AppState>();
|
||
|
||
app.world.run_schedule(OnEnter(AppState::MainMenu));
|
||
assert_eq!(app.world.entities().len(), 2);
|
||
}
|
||
}
|