bevy/examples/ecs/run_conditions.rs
Thierry Berger ced216f59a
Update winit dependency to 0.29 (#10702)
# Objective

- Update winit dependency to 0.29

## Changelog

### KeyCode changes

- Removed `ScanCode`, as it was [replaced by
KeyCode](https://github.com/rust-windowing/winit/blob/master/CHANGELOG.md#0292).
- `ReceivedCharacter.char` is now a `SmolStr`, [relevant
doc](https://docs.rs/winit/latest/winit/event/struct.KeyEvent.html#structfield.text).
- Changed most `KeyCode` values, and added more.

KeyCode has changed meaning. With this PR, it refers to physical
position on keyboard rather than the printed letter on keyboard keys.

In practice this means:
- On QWERTY keyboard layouts, nothing changes
- On any other keyboard layout, `KeyCode` no longer reflects the label
on key.
- This is "good". In bevy 0.12, when you used WASD for movement, users
with non-QWERTY keyboards couldn't play your game! This was especially
bad for non-latin keyboards. Now, WASD represents the physical keys. A
French player will press the ZQSD keys, which are near each other,
Kyrgyz players will use "Цфыв".
- This is "bad" as well. You can't know in advance what the label of the
key for input is. Your UI says "press WASD to move", even if in reality,
they should be pressing "ZQSD" or "Цфыв". You also no longer can use
`KeyCode` for text inputs. In any case, it was a pretty bad API for text
input. You should use `ReceivedCharacter` now instead.

### Other changes
- Use `web-time` rather than `instant` crate.
(https://github.com/rust-windowing/winit/pull/2836)
- winit did split `run_return` in `run_onDemand` and `pump_events`, I
did the same change in bevy_winit and used `pump_events`.
- Removed `return_from_run` from `WinitSettings` as `winit::run` now
returns on supported platforms.
- I left the example "return_after_run" as I think it's still useful.
- This winit change is done partly to allow to create a new window after
quitting all windows: https://github.com/emilk/egui/issues/1918 ; this
PR doesn't address.
- added `width` and `height` properties in the `canvas` from wasm
example
(https://github.com/bevyengine/bevy/pull/10702#discussion_r1420567168)

## Known regressions (important follow ups?)
- Provide an API for reacting when a specific key from current layout
was released.
- possible solutions: use winit::Key from winit::KeyEvent ; mapping
between KeyCode and Key ; or .
- We don't receive characters through alt+numpad (e.g. alt + 151 = "ù")
anymore ; reproduced on winit example "ime". maybe related to
https://github.com/rust-windowing/winit/issues/2945
- (windows) Window content doesn't refresh at all when resizing. By
reading https://github.com/rust-windowing/winit/issues/2900 ; I suspect
we should just fire a `window.request_redraw();` from `AboutToWait`, and
handle actual redrawing within `RedrawRequested`. I'm not sure how to
move all that code so I'd appreciate it to be a follow up.
- (windows) unreleased winit fix for using set_control_flow in
AboutToWait https://github.com/rust-windowing/winit/issues/3215 ; ⚠️ I'm
not sure what the implications are, but that feels bad 🤔

## Follow up 

I'd like to avoid bloating this PR, here are a few follow up tasks
worthy of a separate PR, or new issue to track them once this PR is
closed, as they would either complicate reviews, or at risk of being
controversial:
- remove CanvasParentResizePlugin
(https://github.com/bevyengine/bevy/pull/10702#discussion_r1417068856)
- avoid mentionning explicitly winit in docs from bevy_window ?
- NamedKey integration on bevy_input:
https://github.com/rust-windowing/winit/pull/3143 introduced a new
NamedKey variant. I implemented it only on the converters but we'd
benefit making the same changes to bevy_input.
- Add more info in KeyboardInput
https://github.com/bevyengine/bevy/pull/10702#pullrequestreview-1748336313
- https://github.com/bevyengine/bevy/pull/9905 added a workaround on a
bug allegedly fixed by winit 0.29. We should check if it's still
necessary.
- update to raw_window_handle 0.6
  - blocked by wgpu
- Rename `KeyCode` to `PhysicalKeyCode`
https://github.com/bevyengine/bevy/pull/10702#discussion_r1404595015
- remove `instant` dependency, [replaced
by](https://github.com/rust-windowing/winit/pull/2836) `web_time`), we'd
need to update to :
  - fastrand >= 2.0
- [`async-executor`](https://github.com/smol-rs/async-executor) >= 1.7
    - [`futures-lite`](https://github.com/smol-rs/futures-lite) >= 2.0
- Verify license, see
[discussion](https://github.com/bevyengine/bevy/pull/8745#discussion_r1402439800)
  - we might be missing a short notice or description of changes made
- Consider using https://github.com/rust-windowing/cursor-icon directly
rather than vendoring it in bevy.
- investigate [this
unwrap](https://github.com/bevyengine/bevy/pull/8745#discussion_r1387044986)
(`winit_window.canvas().unwrap();`)
- Use more good things about winit's update
- https://github.com/bevyengine/bevy/pull/10689#issuecomment-1823560428
## Migration Guide

This PR should have one.
2023-12-21 07:40:47 +00:00

106 lines
5.2 KiB
Rust

//! This example demonstrates how to use run conditions to control when systems run.
use bevy::prelude::*;
fn main() {
println!();
println!("For the first 2 seconds you will not be able to increment the counter");
println!("Once that time has passed you can press space, enter, left mouse, right mouse or touch the screen to increment the counter");
println!();
App::new()
.add_plugins(DefaultPlugins)
.init_resource::<InputCounter>()
.add_systems(
Update,
(
increment_input_counter
// The common_conditions module has a few useful run conditions
// for checking resources and states. These are included in the prelude.
.run_if(resource_exists::<InputCounter>())
// `.or_else()` is a run condition combinator that only evaluates the second condition
// if the first condition returns `false`. This behavior is known as "short-circuiting",
// and is how the `||` operator works in Rust (as well as most C-family languages).
// In this case, the `has_user_input` run condition will be evaluated since the `Unused` resource has not been initialized.
.run_if(resource_exists::<Unused>().or_else(
// This is a custom run condition, defined using a system that returns
// a `bool` and which has read-only `SystemParam`s.
// Both run conditions must return `true` in order for the system to run.
// Note that this second run condition will be evaluated even if the first returns `false`.
has_user_input,
)),
print_input_counter
// `.and_then()` is a run condition combinator that only evaluates the second condition
// if the first condition returns `true`, analogous to the `&&` operator.
// In this case, the short-circuiting behavior prevents the second run condition from
// panicking if the `InputCounter` resource has not been initialized.
.run_if(resource_exists::<InputCounter>().and_then(
// This is a custom run condition in the form of a closure.
// This is useful for small, simple run conditions you don't need to reuse.
// All the normal rules still apply: all parameters must be read only except for local parameters.
|counter: Res<InputCounter>| counter.is_changed() && !counter.is_added(),
)),
print_time_message
// This function returns a custom run condition, much like the common conditions module.
// It will only return true once 2 seconds have passed.
.run_if(time_passed(2.0))
// You can use the `not` condition from the common_conditions module
// to inverse a run condition. In this case it will return true if
// less than 2.5 seconds have elapsed since the app started.
.run_if(not(time_passed(2.5))),
),
)
.run();
}
#[derive(Resource, Default)]
struct InputCounter(usize);
#[derive(Resource)]
struct Unused;
/// Return true if any of the defined inputs were just pressed.
/// This is a custom run condition, it can take any normal system parameters as long as
/// they are read only (except for local parameters which can be mutable).
/// It returns a bool which determines if the system should run.
fn has_user_input(
keyboard_input: Res<ButtonInput<KeyCode>>,
mouse_button_input: Res<ButtonInput<MouseButton>>,
touch_input: Res<Touches>,
) -> bool {
keyboard_input.just_pressed(KeyCode::Space)
|| keyboard_input.just_pressed(KeyCode::Enter)
|| mouse_button_input.just_pressed(MouseButton::Left)
|| mouse_button_input.just_pressed(MouseButton::Right)
|| touch_input.any_just_pressed()
}
/// This is a function that returns a closure which can be used as a run condition.
/// This is useful because you can reuse the same run condition but with different variables.
/// This is how the common conditions module works.
fn time_passed(t: f32) -> impl FnMut(Local<f32>, Res<Time>) -> bool {
move |mut timer: Local<f32>, time: Res<Time>| {
// Tick the timer
*timer += time.delta_seconds();
// Return true if the timer has passed the time
*timer >= t
}
}
/// SYSTEM: Increment the input counter
/// Notice how we can take just the `ResMut` and not have to wrap
/// it in an option in case it hasn't been initialized, this is because
/// it has a run condition that checks if the `InputCounter` resource exists
fn increment_input_counter(mut counter: ResMut<InputCounter>) {
counter.0 += 1;
}
/// SYSTEM: Print the input counter
fn print_input_counter(counter: Res<InputCounter>) {
println!("Input counter: {}", counter.0);
}
/// SYSTEM: Adds the input counter resource
fn print_time_message() {
println!("It has been more than 2 seconds since the program started and less than 2.5 seconds");
}