feat: add GamepadInfo, expose gamepad names (bevyengine#6342)

# Objective

Fixes bevyengine#6339.

## Solution

This PR adds a new type, `GamepadInfo`, which holds metadata associated with a particular `Gamepad`. The `Gamepads` resource now holds a `HashMap<Gamepad, GamepadInfo>`. The `GamepadInfo` is created when the gamepad backend (by default `bevy_gilrs`) emits a "gamepad connected" event.

The `gamepad_viewer` example has been updated to showcase the new functionality.

Before:

![bevy-gamepad-old](https://user-images.githubusercontent.com/86984145/197359427-2130a3c0-bd8a-4683-ae24-2a9eaa98b586.png)

After:

![bevy-gamepad-new](https://user-images.githubusercontent.com/86984145/197359429-f7963163-df26-4906-af7f-6186fe3bd338.png)


---

## Changelog

### Added

- Added `GamepadInfo`.
- Added `Gamepads::name()`, which returns the name of the specified gamepad if it exists.

### Changed

- `GamepadEventType::Connected` is now a tuple variant with a single field of type `GamepadInfo`.
- Since `GamepadInfo` is not `Copy`, `GamepadEventType` is no longer `Copy`. The same is true of `GamepadEvent` and `GamepadEventRaw`.

## Migration Guide

- Pattern matches on `GamepadEventType::Connected` will need to be updated, as the form of the variant has changed.
- Code that requires `GamepadEvent`, `GamepadEventRaw` or `GamepadEventType` to be `Copy` will need to be updated.

crates/bevy_gilrs/src/gilrs_system.rs

@@ -1,14 +1,19 @@
 use crate::converter::{convert_axis, convert_button, convert_gamepad_id};
 use bevy_ecs::event::EventWriter;
 use bevy_ecs::system::{NonSend, NonSendMut};
+use bevy_input::gamepad::GamepadInfo;
 use bevy_input::{gamepad::GamepadEventRaw, prelude::*};
 use gilrs::{ev::filter::axis_dpad_to_button, EventType, Filter, Gilrs};
 
 pub fn gilrs_event_startup_system(gilrs: NonSend<Gilrs>, mut events: EventWriter<GamepadEventRaw>) {
-    for (id, _) in gilrs.gamepads() {
+    for (id, gamepad) in gilrs.gamepads() {
+        let info = GamepadInfo {
+            name: gamepad.name().into(),
+        };
+
         events.send(GamepadEventRaw::new(
             convert_gamepad_id(id),
-            GamepadEventType::Connected,
+            GamepadEventType::Connected(info),
         ));
     }
 }
@@ -22,9 +27,14 @@ pub fn gilrs_event_system(mut gilrs: NonSendMut<Gilrs>, mut events: EventWriter<
 
         match gilrs_event.event {
             EventType::Connected => {
+                let pad = gilrs.gamepad(gilrs_event.id);
+                let info = GamepadInfo {
+                    name: pad.name().into(),
+                };
+
                 events.send(GamepadEventRaw::new(
                     convert_gamepad_id(gilrs_event.id),
-                    GamepadEventType::Connected,
+                    GamepadEventType::Connected(info),
                 ));
             }
             EventType::Disconnected => {

crates/bevy_input/src/gamepad.rs

@@ -1,7 +1,7 @@
 use crate::{Axis, Input};
 use bevy_ecs::event::{EventReader, EventWriter};
 use bevy_ecs::system::{Res, ResMut, Resource};
-use bevy_utils::{tracing::info, HashMap, HashSet};
+use bevy_utils::{tracing::info, HashMap};
 use thiserror::Error;
 
 /// Errors that occur when setting axis settings for gamepad input.
@@ -78,6 +78,13 @@ impl Gamepad {
     }
 }
 
+/// Metadata associated with a `Gamepad`.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serialize", derive(serde::Serialize, serde::Deserialize))]
+pub struct GamepadInfo {
+    pub name: String,
+}
+
 /// A collection of connected [`Gamepad`]s.
 ///
 /// ## Usage
@@ -92,23 +99,27 @@ impl Gamepad {
 #[derive(Resource, Default, Debug)]
 pub struct Gamepads {
     /// The collection of the connected [`Gamepad`]s.
-    gamepads: HashSet<Gamepad>,
+    gamepads: HashMap<Gamepad, GamepadInfo>,
 }
 
 impl Gamepads {
     /// Returns `true` if the `gamepad` is connected.
     pub fn contains(&self, gamepad: Gamepad) -> bool {
-        self.gamepads.contains(&gamepad)
+        self.gamepads.contains_key(&gamepad)
     }
 
     /// Returns an iterator over registered [`Gamepad`]s in an arbitrary order.
     pub fn iter(&self) -> impl Iterator<Item = Gamepad> + '_ {
-        self.gamepads.iter().copied()
+        self.gamepads.keys().copied()
+    }
+
+    pub fn name(&self, gamepad: Gamepad) -> Option<&str> {
+        self.gamepads.get(&gamepad).map(|g| g.name.as_str())
     }
 
     /// Registers the `gamepad`, marking it as connected.
-    fn register(&mut self, gamepad: Gamepad) {
-        self.gamepads.insert(gamepad);
+    fn register(&mut self, gamepad: Gamepad, info: GamepadInfo) {
+        self.gamepads.insert(gamepad, info);
     }
 
     /// Deregisters the `gamepad`, marking it as disconnected.
@@ -118,11 +129,11 @@ impl Gamepads {
 }
 
 /// The data contained in a [`GamepadEvent`] or [`GamepadEventRaw`].
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, PartialEq)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize, serde::Deserialize))]
 pub enum GamepadEventType {
     /// A [`Gamepad`] has been connected.
-    Connected,
+    Connected(GamepadInfo),
     /// A [`Gamepad`] has been disconnected.
     Disconnected,
 
@@ -151,7 +162,7 @@ pub enum GamepadEventType {
 /// [`Axis<GamepadAxis>`], and [`Axis<GamepadButton>`] resources won't be updated correctly.
 ///
 /// An example for gamepad input mocking can be seen in the documentation of the [`GamepadEventRaw`].
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, PartialEq)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize, serde::Deserialize))]
 pub struct GamepadEvent {
     /// The gamepad this event corresponds to.
@@ -191,7 +202,7 @@ impl GamepadEvent {
 /// ```
 /// # use bevy_input::prelude::*;
 /// # use bevy_input::InputPlugin;
-/// # use bevy_input::gamepad::GamepadEventRaw;
+/// # use bevy_input::gamepad::{GamepadEventRaw, GamepadInfo};
 /// # use bevy_app::prelude::*;
 /// # use bevy_ecs::prelude::*;
 /// #[derive(Resource)]
@@ -223,7 +234,8 @@ impl GamepadEvent {
 ///
 /// // Send the gamepad connected event to mark our gamepad as connected.
 /// // This updates the `Gamepads` resource accordingly.
-/// app.world.send_event(GamepadEventRaw::new(gamepad, GamepadEventType::Connected));
+/// let info = GamepadInfo { name: "Mock Gamepad".into() };
+/// app.world.send_event(GamepadEventRaw::new(gamepad, GamepadEventType::Connected(info)));
 ///
 /// // Send the gamepad input event to mark the `South` gamepad button as pressed.
 /// // This updates the `Input<GamepadButton>` resource accordingly.
@@ -254,7 +266,7 @@ impl GamepadEvent {
 /// #
 /// # bevy_ecs::system::assert_is_system(change_resource_on_gamepad_button_press);
 /// ```
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, PartialEq)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize, serde::Deserialize))]
 pub struct GamepadEventRaw {
     /// The gamepad this event corresponds to.
@@ -1062,11 +1074,12 @@ pub fn gamepad_connection_system(
     mut gamepad_event: EventReader<GamepadEvent>,
 ) {
     for event in gamepad_event.iter() {
-        match event.event_type {
-            GamepadEventType::Connected => {
-                gamepads.register(event.gamepad);
+        match &event.event_type {
+            GamepadEventType::Connected(info) => {
+                gamepads.register(event.gamepad, info.clone());
                 info!("{:?} Connected", event.gamepad);
             }
+
             GamepadEventType::Disconnected => {
                 gamepads.deregister(event.gamepad);
                 info!("{:?} Disconnected", event.gamepad);
@@ -1096,9 +1109,9 @@ pub fn gamepad_event_system(
 ) {
     button_input.clear();
     for event in raw_events.iter() {
-        match event.event_type {
-            GamepadEventType::Connected => {
-                events.send(GamepadEvent::new(event.gamepad, event.event_type));
+        match &event.event_type {
+            GamepadEventType::Connected(_) => {
+                events.send(GamepadEvent::new(event.gamepad, event.event_type.clone()));
                 for button_type in &ALL_BUTTON_TYPES {
                     let gamepad_button = GamepadButton::new(event.gamepad, *button_type);
                     button_input.reset(gamepad_button);
@@ -1109,7 +1122,7 @@ pub fn gamepad_event_system(
                 }
             }
             GamepadEventType::Disconnected => {
-                events.send(GamepadEvent::new(event.gamepad, event.event_type));
+                events.send(GamepadEvent::new(event.gamepad, event.event_type.clone()));
                 for button_type in &ALL_BUTTON_TYPES {
                     let gamepad_button = GamepadButton::new(event.gamepad, *button_type);
                     button_input.reset(gamepad_button);
@@ -1120,37 +1133,37 @@ pub fn gamepad_event_system(
                 }
             }
             GamepadEventType::AxisChanged(axis_type, value) => {
-                let gamepad_axis = GamepadAxis::new(event.gamepad, axis_type);
+                let gamepad_axis = GamepadAxis::new(event.gamepad, *axis_type);
                 if let Some(filtered_value) = settings
                     .get_axis_settings(gamepad_axis)
-                    .filter(value, axis.get(gamepad_axis))
+                    .filter(*value, axis.get(gamepad_axis))
                 {
                     axis.set(gamepad_axis, filtered_value);
                     events.send(GamepadEvent::new(
                         event.gamepad,
-                        GamepadEventType::AxisChanged(axis_type, filtered_value),
+                        GamepadEventType::AxisChanged(*axis_type, filtered_value),
                     ));
                 }
             }
             GamepadEventType::ButtonChanged(button_type, value) => {
-                let gamepad_button = GamepadButton::new(event.gamepad, button_type);
+                let gamepad_button = GamepadButton::new(event.gamepad, *button_type);
                 if let Some(filtered_value) = settings
                     .get_button_axis_settings(gamepad_button)
-                    .filter(value, button_axis.get(gamepad_button))
+                    .filter(*value, button_axis.get(gamepad_button))
                 {
                     button_axis.set(gamepad_button, filtered_value);
                     events.send(GamepadEvent::new(
                         event.gamepad,
-                        GamepadEventType::ButtonChanged(button_type, filtered_value),
+                        GamepadEventType::ButtonChanged(*button_type, filtered_value),
                     ));
                 }
 
                 let button_property = settings.get_button_settings(gamepad_button);
                 if button_input.pressed(gamepad_button) {
-                    if button_property.is_released(value) {
+                    if button_property.is_released(*value) {
                         button_input.release(gamepad_button);
                     }
-                } else if button_property.is_pressed(value) {
+                } else if button_property.is_pressed(*value) {
                     button_input.press(gamepad_button);
                 }
             }

examples/input/gamepad_input_events.rs

@@ -15,7 +15,7 @@ fn main() {
 fn gamepad_events(mut gamepad_event: EventReader<GamepadEvent>) {
     for event in gamepad_event.iter() {
         match event.event_type {
-            GamepadEventType::Connected => {
+            GamepadEventType::Connected(_) => {
                 info!("{:?} Connected", event.gamepad);
             }
             GamepadEventType::Disconnected => {

examples/tools/gamepad_viewer.rs

@@ -437,7 +437,7 @@ fn setup_connected(mut commands: Commands, font: Res<FontHandle>) {
     commands.spawn((
         TextBundle::from_sections([
             TextSection {
-                value: "Connected Gamepads\n".to_string(),
+                value: "Connected Gamepads:\n".to_string(),
                 style: style.clone(),
             },
             TextSection {
@@ -521,7 +521,7 @@ fn update_connected(
 
     let formatted = gamepads
         .iter()
-        .map(|g| format!("{:?}", g))
+        .map(|g| format!("- {}", gamepads.name(g).unwrap()))
         .collect::<Vec<_>>()
         .join("\n");