b8263b55fb
# Objective
Support the following syntax for adding systems:
```rust
App::new()
.add_system(setup.on_startup())
.add_systems((
show_menu.in_schedule(OnEnter(GameState::Paused)),
menu_ssytem.in_set(OnUpdate(GameState::Paused)),
hide_menu.in_schedule(OnExit(GameState::Paused)),
))
```
## Solution
Add the traits `IntoSystemAppConfig{s}`, which provide the extension methods necessary for configuring which schedule a system belongs to. These extension methods return `IntoSystemAppConfig{s}`, which `App::add_system{s}` uses to choose which schedule to add systems to.
---
## Changelog
+ Added the extension methods `in_schedule(label)` and `on_startup()` for configuring the schedule a system belongs to.
## Future Work
* Replace all uses of `add_startup_system` in the engine.
* Deprecate this method
39 lines
1.2 KiB
Rust
39 lines
1.2 KiB
Rust
//! Shows how to create systems that run every fixed timestep, rather than every tick.
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use bevy::prelude::*;
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const FIXED_TIMESTEP: f32 = 0.5;
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fn main() {
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App::new()
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.add_plugins(DefaultPlugins)
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// this system will run once every update (it should match your screen's refresh rate)
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.add_system(frame_update)
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// add our system to the fixed timestep schedule
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.add_system(fixed_update.in_schedule(CoreSchedule::FixedUpdate))
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// configure our fixed timestep schedule to run twice a second
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.insert_resource(FixedTime::new_from_secs(FIXED_TIMESTEP))
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.run();
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}
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fn frame_update(mut last_time: Local<f32>, time: Res<Time>) {
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info!(
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"time since last frame_update: {}",
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time.raw_elapsed_seconds() - *last_time
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);
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*last_time = time.raw_elapsed_seconds();
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}
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fn fixed_update(mut last_time: Local<f32>, time: Res<Time>, fixed_time: Res<FixedTime>) {
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info!(
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"time since last fixed_update: {}\n",
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time.raw_elapsed_seconds() - *last_time
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);
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info!("fixed timestep: {}\n", FIXED_TIMESTEP);
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info!(
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"time accrued toward next fixed_update: {}\n",
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fixed_time.accumulated().as_secs_f32()
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);
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*last_time = time.raw_elapsed_seconds();
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}
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