bevy/crates/bevy_input/src/lib.rs
Carter Anderson dcc03724a5 Base Sets (#7466)
# Objective

NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267.

"Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365).

## Solution

This adds "base sets" as a variant of `SystemSet`:

A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive:

```rust
#[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)]
#[system_set(base)]
enum MyBaseSet {
  A,
  B,
}
``` 

**Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build. 

**Base sets cannot belong to other sets**: this is where the word "base" comes from

Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set.

```rust
app.add_system(foo.in_base_set(MyBaseSet::A))
       // X must be a normal set ... base sets cannot be added to base sets
       .configure_set(X.in_base_set(MyBaseSet::A))
```

Base sets can still be configured like normal sets:

```rust
app.add_system(MyBaseSet::B.after(MyBaseSet::Ap))
``` 

The primary use case for base sets is enabling a "default base set":

```rust
schedule.set_default_base_set(CoreSet::Update)
  // this will belong to CoreSet::Update by default
  .add_system(foo)
  // this will override the default base set with PostUpdate
  .add_system(bar.in_base_set(CoreSet::PostUpdate))
```

This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides.

---

## Changelog

- Added "base sets" and ported CoreSet to use them.

## Migration Guide

TODO
2023-02-06 03:10:08 +00:00

146 lines
4.8 KiB
Rust

mod axis;
pub mod gamepad;
mod input;
pub mod keyboard;
pub mod mouse;
pub mod touch;
pub use axis::*;
pub use input::*;
pub mod prelude {
#[doc(hidden)]
pub use crate::{
gamepad::{
Gamepad, GamepadAxis, GamepadAxisType, GamepadButton, GamepadButtonType, Gamepads,
},
keyboard::{KeyCode, ScanCode},
mouse::MouseButton,
touch::{TouchInput, Touches},
Axis, Input,
};
}
use bevy_app::prelude::*;
use bevy_ecs::prelude::*;
use bevy_reflect::{FromReflect, Reflect};
use keyboard::{keyboard_input_system, KeyCode, KeyboardInput, ScanCode};
use mouse::{
mouse_button_input_system, MouseButton, MouseButtonInput, MouseMotion, MouseScrollUnit,
MouseWheel,
};
use touch::{touch_screen_input_system, ForceTouch, TouchInput, TouchPhase, Touches};
use gamepad::{
gamepad_axis_event_system, gamepad_button_event_system, gamepad_connection_system,
gamepad_event_system, AxisSettings, ButtonAxisSettings, ButtonSettings, Gamepad, GamepadAxis,
GamepadAxisChangedEvent, GamepadAxisType, GamepadButton, GamepadButtonChangedEvent,
GamepadButtonType, GamepadConnection, GamepadConnectionEvent, GamepadEvent, GamepadSettings,
Gamepads,
};
#[cfg(feature = "serialize")]
use bevy_reflect::{ReflectDeserialize, ReflectSerialize};
/// Adds keyboard and mouse input to an App
#[derive(Default)]
pub struct InputPlugin;
#[derive(Debug, PartialEq, Eq, Clone, Hash, SystemSet)]
pub struct InputSystem;
impl Plugin for InputPlugin {
fn build(&self, app: &mut App) {
app.configure_set(InputSystem.in_base_set(CoreSet::PreUpdate))
// keyboard
.add_event::<KeyboardInput>()
.init_resource::<Input<KeyCode>>()
.init_resource::<Input<ScanCode>>()
.add_system(keyboard_input_system.in_set(InputSystem))
// mouse
.add_event::<MouseButtonInput>()
.add_event::<MouseMotion>()
.add_event::<MouseWheel>()
.init_resource::<Input<MouseButton>>()
.add_system(mouse_button_input_system.in_set(InputSystem))
// gamepad
.add_event::<GamepadConnectionEvent>()
.add_event::<GamepadButtonChangedEvent>()
.add_event::<GamepadAxisChangedEvent>()
.add_event::<GamepadEvent>()
.init_resource::<GamepadSettings>()
.init_resource::<Gamepads>()
.init_resource::<Input<GamepadButton>>()
.init_resource::<Axis<GamepadAxis>>()
.init_resource::<Axis<GamepadButton>>()
.add_systems(
(
gamepad_event_system,
gamepad_connection_system.after(gamepad_event_system),
gamepad_button_event_system
.after(gamepad_event_system)
.after(gamepad_connection_system),
gamepad_axis_event_system
.after(gamepad_event_system)
.after(gamepad_connection_system),
)
.in_set(InputSystem),
)
// touch
.add_event::<TouchInput>()
.init_resource::<Touches>()
.add_system(touch_screen_input_system.in_set(InputSystem));
// Register common types
app.register_type::<ButtonState>();
// Register keyboard types
app.register_type::<KeyboardInput>()
.register_type::<KeyCode>()
.register_type::<ScanCode>();
// Register mouse types
app.register_type::<MouseButtonInput>()
.register_type::<MouseButton>()
.register_type::<MouseMotion>()
.register_type::<MouseScrollUnit>()
.register_type::<MouseWheel>();
// Register touch types
app.register_type::<TouchInput>()
.register_type::<ForceTouch>()
.register_type::<TouchPhase>();
// Register gamepad types
app.register_type::<Gamepad>()
.register_type::<GamepadConnection>()
.register_type::<GamepadButtonType>()
.register_type::<GamepadButton>()
.register_type::<GamepadAxisType>()
.register_type::<GamepadAxis>()
.register_type::<GamepadSettings>()
.register_type::<ButtonSettings>()
.register_type::<AxisSettings>()
.register_type::<ButtonAxisSettings>();
}
}
/// The current "press" state of an element
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash, Reflect, FromReflect)]
#[reflect(Debug, Hash, PartialEq)]
#[cfg_attr(
feature = "serialize",
derive(serde::Serialize, serde::Deserialize),
reflect(Serialize, Deserialize)
)]
pub enum ButtonState {
Pressed,
Released,
}
impl ButtonState {
pub fn is_pressed(&self) -> bool {
matches!(self, ButtonState::Pressed)
}
}