small input example improvements (#701)

Cargo.toml

@@ -235,8 +235,8 @@ name = "touch_input"
 path = "examples/input/touch_input.rs"
 
 [[example]]
-name = "touch_input_highlevel"
-path = "examples/input/touch_input_highlevel.rs"
+name = "touch_input_events"
+path = "examples/input/touch_input_events.rs"
 
 [[example]]
 name = "scene"

crates/bevy_input/src/touch.rs

@@ -98,22 +98,18 @@ pub fn touch_screen_input_system(
     mut touch_state: ResMut<Touches>,
     touch_input_events: Res<Events<TouchInput>>,
 ) {
-    touch_state.just_pressed.clear();
-
-    let released_touch_ids: HashSet<_> = touch_state.just_released.iter().cloned().collect();
-    let cancelled_touch_ids: HashSet<_> = touch_state.just_released.iter().cloned().collect();
-
-    touch_state.just_released.clear();
-    touch_state.just_cancelled.clear();
-
-    for released_id in released_touch_ids {
+    let touch_state = &mut *touch_state;
+    for released_id in touch_state.just_released.iter() {
         touch_state.active_touches.remove(&released_id);
     }
 
-    for cancelled_id in cancelled_touch_ids {
+    for cancelled_id in touch_state.just_cancelled.iter() {
         touch_state.active_touches.remove(&cancelled_id);
     }
 
+    touch_state.just_pressed.clear();
+    touch_state.just_cancelled.clear();
+
     for event in state.touch_event_reader.iter(&touch_input_events) {
         let active_touch = touch_state.active_touches.get(&event.id);
         match event.phase {

examples/input/gamepad_input.rs

@@ -9,25 +9,25 @@ fn main() {
         .add_system(connection_system.system())
         .add_system(button_system.system())
         .add_system(axis_system.system())
-        .add_resource(Lobby::default())
+        .init_resource::<GamepadLobby>()
         .run();
 }
 
 #[derive(Default)]
-struct Lobby {
-    gamepad: HashSet<Gamepad>,
+struct GamepadLobby {
+    gamepads: HashSet<Gamepad>,
     gamepad_event_reader: EventReader<GamepadEvent>,
 }
 
-fn connection_system(mut lobby: ResMut<Lobby>, gamepad_event: Res<Events<GamepadEvent>>) {
+fn connection_system(mut lobby: ResMut<GamepadLobby>, gamepad_event: Res<Events<GamepadEvent>>) {
     for event in lobby.gamepad_event_reader.iter(&gamepad_event) {
         match &event {
             GamepadEvent(gamepad, GamepadEventType::Connected) => {
-                lobby.gamepad.insert(*gamepad);
+                lobby.gamepads.insert(*gamepad);
                 println!("Connected {:?}", gamepad);
             }
             GamepadEvent(gamepad, GamepadEventType::Disconnected) => {
-                lobby.gamepad.remove(gamepad);
+                lobby.gamepads.remove(gamepad);
                 println!("Disconnected {:?}", gamepad);
             }
         }
@@ -35,7 +35,7 @@ fn connection_system(mut lobby: ResMut<Lobby>, gamepad_event: Res<Events<Gamepad
 }
 
 fn button_system(
-    manager: Res<Lobby>,
+    lobby: Res<GamepadLobby>,
     inputs: Res<Input<GamepadButton>>,
     button_axes: Res<Axis<GamepadButton>>,
 ) {
@@ -60,7 +60,7 @@ fn button_system(
         GamepadButtonType::DPadLeft,
         GamepadButtonType::DPadRight,
     ];
-    for gamepad in manager.gamepad.iter() {
+    for gamepad in lobby.gamepads.iter() {
         for button_type in button_types.iter() {
             if inputs.just_pressed(GamepadButton(*gamepad, *button_type)) {
                 println!("Pressed {:?}", GamepadButton(*gamepad, *button_type));
@@ -80,7 +80,7 @@ fn button_system(
     }
 }
 
-fn axis_system(manager: Res<Lobby>, axes: Res<Axis<GamepadAxis>>) {
+fn axis_system(lobby: Res<GamepadLobby>, axes: Res<Axis<GamepadAxis>>) {
     let axis_types = [
         GamepadAxisType::LeftStickX,
         GamepadAxisType::LeftStickY,
@@ -91,7 +91,7 @@ fn axis_system(manager: Res<Lobby>, axes: Res<Axis<GamepadAxis>>) {
         GamepadAxisType::DPadX,
         GamepadAxisType::DPadY,
     ];
-    for gamepad in manager.gamepad.iter() {
+    for gamepad in lobby.gamepads.iter() {
         for axis_type in axis_types.iter() {
             if let Some(value) = axes.get(&GamepadAxis(*gamepad, *axis_type)) {
                 if value_check(value) {

examples/input/keyboard_input_events.rs

@@ -3,7 +3,6 @@ use bevy::{input::keyboard::KeyboardInput, prelude::*};
 fn main() {
     App::build()
         .add_default_plugins()
-        .init_resource::<State>()
         .add_system(print_keyboard_event_system.system())
         .run();
 }
@@ -15,7 +14,7 @@ struct State {
 
 /// This system prints out all keyboard events as they come in
 fn print_keyboard_event_system(
-    mut state: ResMut<State>,
+    mut state: Local<State>,
     keyboard_input_events: Res<Events<KeyboardInput>>,
 ) {
     for event in state.event_reader.iter(&keyboard_input_events) {

examples/input/mouse_input_events.rs

@@ -7,7 +7,6 @@ use bevy::{
 fn main() {
     App::build()
         .add_default_plugins()
-        .init_resource::<State>()
         .add_system(print_mouse_events_system.system())
         .run();
 }
@@ -22,7 +21,7 @@ struct State {
 
 /// This system prints out all mouse events as they come in
 fn print_mouse_events_system(
-    mut state: ResMut<State>,
+    mut state: Local<State>,
     mouse_button_input_events: Res<Events<MouseButtonInput>>,
     mouse_motion_events: Res<Events<MouseMotion>>,
     cursor_moved_events: Res<Events<CursorMoved>>,

examples/input/touch_input.rs

@@ -8,28 +8,27 @@ fn main() {
 }
 
 fn touch_system(touches: Res<Touches>) {
-    for touch in touches.iter() {
+    for touch in touches.iter_just_pressed() {
         println!(
-            "active touch: {} {} {} {}",
-            touch.id, touch.position, touch.previous_position, touch.start_position
+            "just pressed touch with id: {:?}, at: {:?}",
+            touch.id, touch.position
         );
+    }
 
-        if touches.just_pressed(touch.id) {
-            println!(
-                "just pressed touch with id: {:?}, at: {:?}",
-                touch.id, touch.position
-            );
-        }
+    for touch in touches.iter_just_released() {
+        println!(
+            "just released touch with id: {:?}, at: {:?}",
+            touch.id, touch.position
+        );
+    }
 
-        if touches.just_released(touch.id) {
-            println!(
-                "just released touch with id: {:?}, at: {:?}",
-                touch.id, touch.position
-            );
-        }
+    for touch in touches.iter_just_cancelled() {
+        println!("cancelled touch with id: {:?}", touch.id);
+    }
 
-        if touches.just_cancelled(touch.id) {
-            println!("cancelled touch with id: {:?}", touch.id);
-        }
+    // you can also iterate all current touches and retrieve their state like this:
+    for touch in touches.iter() {
+        println!("active touch: {:?}", touch);
+        println!("  just_pressed: {}", touches.just_pressed(touch.id));
     }
 }

examples/input/touch_input_events.rs

@@ -0,0 +1,19 @@
+use bevy::{input::touch::*, prelude::*};
+
+fn main() {
+    App::build()
+        .add_default_plugins()
+        .add_system(touch_event_system.system())
+        .run();
+}
+
+#[derive(Default)]
+struct State {
+    event_reader: EventReader<TouchInput>,
+}
+
+fn touch_event_system(mut state: Local<State>, touch_events: Res<Events<TouchInput>>) {
+    for event in state.event_reader.iter(&touch_events) {
+        println!("{:?}", event);
+    }
+}

examples/input/touch_input_highlevel.rs

@@ -1,28 +0,0 @@
-use bevy::{input::touch::*, prelude::*};
-
-fn main() {
-    App::build()
-        .add_default_plugins()
-        .add_system(touch_system.system())
-        .run();
-}
-
-fn touch_system(touches: Res<Touches>) {
-    for touch in touches.iter_just_pressed() {
-        println!(
-            "just pressed touch with id: {:?}, at: {:?}",
-            touch.id, touch.position
-        );
-    }
-
-    for touch in touches.iter_just_released() {
-        println!(
-            "just released touch with id: {:?}, at: {:?}",
-            touch.id, touch.position
-        );
-    }
-
-    for touch in touches.iter_just_cancelled() {
-        println!("cancelled touch with id: {:?}", touch.id);
-    }
-}