Separate unrelated code to submodules in compute/sub-state examples (#13188)

Large part of the code is UI spawning which contributes nothing to the
code example.

examples/ecs/computed_states.rs

@@ -18,6 +18,8 @@
 
 use bevy::prelude::*;
 
+use ui::*;
+
 // To begin, we want to define our state objects.
 #[derive(Debug, Clone, Copy, Default, Eq, PartialEq, Hash, States)]
 enum AppState {
@@ -221,30 +223,158 @@ fn main() {
         .run();
 }
 
-#[derive(Resource)]
+fn menu(
-struct MenuData {
+    mut next_state: ResMut<NextState<AppState>>,
-    root_entity: Entity,
+    tutorial_state: Res<State<TutorialState>>,
+    mut next_tutorial: ResMut<NextState<TutorialState>>,
+    mut interaction_query: Query<
+        (&Interaction, &mut UiImage, &MenuButton),
+        (Changed<Interaction>, With<Button>),
+    >,
+) {
+    for (interaction, mut image, menu_button) in &mut interaction_query {
+        let color = &mut image.color;
+        match *interaction {
+            Interaction::Pressed => {
+                *color = if menu_button == &MenuButton::Tutorial
+                    && tutorial_state.get() == &TutorialState::Active
+                {
+                    PRESSED_ACTIVE_BUTTON
+                } else {
+                    PRESSED_BUTTON
+                };
+
+                match menu_button {
+                    MenuButton::Play => next_state.set(AppState::InGame {
+                        paused: false,
+                        turbo: false,
+                    }),
+                    MenuButton::Tutorial => next_tutorial.set(match tutorial_state.get() {
+                        TutorialState::Active => TutorialState::Inactive,
+                        TutorialState::Inactive => TutorialState::Active,
+                    }),
+                };
+            }
+            Interaction::Hovered => {
+                if menu_button == &MenuButton::Tutorial
+                    && tutorial_state.get() == &TutorialState::Active
+                {
+                    *color = HOVERED_ACTIVE_BUTTON;
+                } else {
+                    *color = HOVERED_BUTTON;
+                }
+            }
+            Interaction::None => {
+                if menu_button == &MenuButton::Tutorial
+                    && tutorial_state.get() == &TutorialState::Active
+                {
+                    *color = ACTIVE_BUTTON;
+                } else {
+                    *color = NORMAL_BUTTON;
+                }
+            }
+        }
+    }
 }
 
-#[derive(Component, PartialEq, Eq)]
+#[derive(Component)]
-enum MenuButton {
+struct StateBound<S: States>(S);
+
+fn clear_state_bound_entities<S: States>(
+    state: S,
+) -> impl Fn(Commands, Query<(Entity, &StateBound<S>)>) {
+    info!("Clearing entities for {state:?}");
+    move |mut commands, query| {
+        for (entity, bound) in &query {
+            if bound.0 == state {
+                commands.entity(entity).despawn_recursive();
+            }
+        }
+    }
+}
+
+fn toggle_pause(
+    input: Res<ButtonInput<KeyCode>>,
+    current_state: Res<State<AppState>>,
+    mut next_state: ResMut<NextState<AppState>>,
+) {
+    if input.just_pressed(KeyCode::Space) {
+        if let AppState::InGame { paused, turbo } = current_state.get() {
+            next_state.set(AppState::InGame {
+                paused: !*paused,
+                turbo: *turbo,
+            });
+        }
+    }
+}
+
+fn toggle_turbo(
+    input: Res<ButtonInput<KeyCode>>,
+    current_state: Res<State<AppState>>,
+    mut next_state: ResMut<NextState<AppState>>,
+) {
+    if input.just_pressed(KeyCode::KeyT) {
+        if let AppState::InGame { paused, turbo } = current_state.get() {
+            next_state.set(AppState::InGame {
+                paused: *paused,
+                turbo: !*turbo,
+            });
+        }
+    }
+}
+
+fn quit_to_menu(input: Res<ButtonInput<KeyCode>>, mut next_state: ResMut<NextState<AppState>>) {
+    if input.just_pressed(KeyCode::Escape) {
+        next_state.set(AppState::Menu);
+    }
+}
+
+/// print when either an `AppState` transition or a `TutorialState` transition happens
+fn log_transitions(
+    mut transitions: EventReader<StateTransitionEvent<AppState>>,
+    mut tutorial_transitions: EventReader<StateTransitionEvent<TutorialState>>,
+) {
+    for transition in transitions.read() {
+        info!(
+            "transition: {:?} => {:?}",
+            transition.before, transition.after
+        );
+    }
+    for transition in tutorial_transitions.read() {
+        info!(
+            "tutorial transition: {:?} => {:?}",
+            transition.before, transition.after
+        );
+    }
+}
+
+mod ui {
+    use crate::*;
+
+    #[derive(Resource)]
+    pub struct MenuData {
+        pub root_entity: Entity,
+    }
+
+    #[derive(Component, PartialEq, Eq)]
+    pub enum MenuButton {
         Play,
         Tutorial,
-}
+    }
 
-const NORMAL_BUTTON: Color = Color::srgb(0.15, 0.15, 0.15);
+    pub const NORMAL_BUTTON: Color = Color::srgb(0.15, 0.15, 0.15);
-const HOVERED_BUTTON: Color = Color::srgb(0.25, 0.25, 0.25);
+    pub const HOVERED_BUTTON: Color = Color::srgb(0.25, 0.25, 0.25);
-const PRESSED_BUTTON: Color = Color::srgb(0.35, 0.75, 0.35);
+    pub const PRESSED_BUTTON: Color = Color::srgb(0.35, 0.75, 0.35);
 
-const ACTIVE_BUTTON: Color = Color::srgb(0.15, 0.85, 0.15);
+    pub const ACTIVE_BUTTON: Color = Color::srgb(0.15, 0.85, 0.15);
-const HOVERED_ACTIVE_BUTTON: Color = Color::srgb(0.25, 0.55, 0.25);
+    pub const HOVERED_ACTIVE_BUTTON: Color = Color::srgb(0.25, 0.55, 0.25);
-const PRESSED_ACTIVE_BUTTON: Color = Color::srgb(0.35, 0.95, 0.35);
+    pub const PRESSED_ACTIVE_BUTTON: Color = Color::srgb(0.35, 0.95, 0.35);
 
-fn setup(mut commands: Commands) {
+    pub fn setup(mut commands: Commands) {
         commands.spawn(Camera2dBundle::default());
-}
+    }
 
-fn setup_menu(mut commands: Commands, tutorial_state: Res<State<TutorialState>>) {
+    pub fn setup_menu(mut commands: Commands, tutorial_state: Res<State<TutorialState>>) {
         let button_entity = commands
             .spawn(NodeBundle {
                 style: Style {
@@ -323,70 +453,13 @@ fn setup_menu(mut commands: Commands, tutorial_state: Res<State<TutorialState>>)
         commands.insert_resource(MenuData {
             root_entity: button_entity,
         });
-}
+    }
 
-fn menu(
+    pub fn cleanup_menu(mut commands: Commands, menu_data: Res<MenuData>) {
-    mut next_state: ResMut<NextState<AppState>>,
-    tutorial_state: Res<State<TutorialState>>,
-    mut next_tutorial: ResMut<NextState<TutorialState>>,
-    mut interaction_query: Query<
-        (&Interaction, &mut UiImage, &MenuButton),
-        (Changed<Interaction>, With<Button>),
-    >,
-) {
-    for (interaction, mut image, menu_button) in &mut interaction_query {
-        let color = &mut image.color;
-        match *interaction {
-            Interaction::Pressed => {
-                *color = if menu_button == &MenuButton::Tutorial
-                    && tutorial_state.get() == &TutorialState::Active
-                {
-                    PRESSED_ACTIVE_BUTTON
-                } else {
-                    PRESSED_BUTTON
-                };
-
-                match menu_button {
-                    MenuButton::Play => next_state.set(AppState::InGame {
-                        paused: false,
-                        turbo: false,
-                    }),
-                    MenuButton::Tutorial => next_tutorial.set(match tutorial_state.get() {
-                        TutorialState::Active => TutorialState::Inactive,
-                        TutorialState::Inactive => TutorialState::Active,
-                    }),
-                };
-            }
-            Interaction::Hovered => {
-                if menu_button == &MenuButton::Tutorial
-                    && tutorial_state.get() == &TutorialState::Active
-                {
-                    *color = HOVERED_ACTIVE_BUTTON;
-                } else {
-                    *color = HOVERED_BUTTON;
-                }
-            }
-            Interaction::None => {
-                if menu_button == &MenuButton::Tutorial
-                    && tutorial_state.get() == &TutorialState::Active
-                {
-                    *color = ACTIVE_BUTTON;
-                } else {
-                    *color = NORMAL_BUTTON;
-                }
-            }
-        }
-    }
-}
-
-fn cleanup_menu(mut commands: Commands, menu_data: Res<MenuData>) {
         commands.entity(menu_data.root_entity).despawn_recursive();
-}
+    }
 
-#[derive(Component)]
+    pub fn setup_game(mut commands: Commands, asset_server: Res<AssetServer>) {
-struct StateBound<S: States>(S);
-
-fn setup_game(mut commands: Commands, asset_server: Res<AssetServer>) {
         commands.spawn((
             StateBound(InGame),
             SpriteBundle {
@@ -394,29 +467,17 @@ fn setup_game(mut commands: Commands, asset_server: Res<AssetServer>) {
                 ..default()
             },
         ));
-}
+    }
 
-fn clear_state_bound_entities<S: States>(
+    const SPEED: f32 = 100.0;
-    state: S,
+    const TURBO_SPEED: f32 = 300.0;
-) -> impl Fn(Commands, Query<(Entity, &StateBound<S>)>) {
-    info!("Clearing entities for {state:?}");
-    move |mut commands, query| {
-        for (entity, bound) in &query {
-            if bound.0 == state {
-                commands.entity(entity).despawn_recursive();
-            }
-        }
-    }
-}
 
-const SPEED: f32 = 100.0;
+    pub fn movement(
-const TURBO_SPEED: f32 = 300.0;
-fn movement(
         time: Res<Time>,
         input: Res<ButtonInput<KeyCode>>,
         turbo: Option<Res<State<TurboMode>>>,
         mut query: Query<&mut Transform, With<Sprite>>,
-) {
+    ) {
         for mut transform in &mut query {
             let mut direction = Vec3::ZERO;
             if input.pressed(KeyCode::ArrowLeft) {
@@ -438,24 +499,9 @@ fn movement(
                     * time.delta_seconds();
             }
         }
-}
-
-fn toggle_pause(
-    input: Res<ButtonInput<KeyCode>>,
-    current_state: Res<State<AppState>>,
-    mut next_state: ResMut<NextState<AppState>>,
-) {
-    if input.just_pressed(KeyCode::Space) {
-        if let AppState::InGame { paused, turbo } = current_state.get() {
-            next_state.set(AppState::InGame {
-                paused: !*paused,
-                turbo: *turbo,
-            });
     }
-    }
-}
 
-fn setup_paused_screen(mut commands: Commands) {
+    pub fn setup_paused_screen(mut commands: Commands) {
         info!("Printing Pause");
         commands
             .spawn((
@@ -504,24 +550,9 @@ fn setup_paused_screen(mut commands: Commands) {
                         ));
                     });
             });
-}
-
-fn toggle_turbo(
-    input: Res<ButtonInput<KeyCode>>,
-    current_state: Res<State<AppState>>,
-    mut next_state: ResMut<NextState<AppState>>,
-) {
-    if input.just_pressed(KeyCode::KeyT) {
-        if let AppState::InGame { paused, turbo } = current_state.get() {
-            next_state.set(AppState::InGame {
-                paused: *paused,
-                turbo: !*turbo,
-            });
     }
-    }
-}
 
-fn setup_turbo_text(mut commands: Commands) {
+    pub fn setup_turbo_text(mut commands: Commands) {
         commands
             .spawn((
                 StateBound(TurboMode),
@@ -550,15 +581,9 @@ fn setup_turbo_text(mut commands: Commands) {
                     },
                 ));
             });
-}
-
-fn quit_to_menu(input: Res<ButtonInput<KeyCode>>, mut next_state: ResMut<NextState<AppState>>) {
-    if input.just_pressed(KeyCode::Escape) {
-        next_state.set(AppState::Menu);
     }
-}
 
-fn change_color(time: Res<Time>, mut query: Query<&mut Sprite>) {
+    pub fn change_color(time: Res<Time>, mut query: Query<&mut Sprite>) {
         for mut sprite in &mut query {
             let new_color = LinearRgba {
                 blue: (time.elapsed_seconds() * 0.5).sin() + 2.0,
@@ -567,9 +592,9 @@ fn change_color(time: Res<Time>, mut query: Query<&mut Sprite>) {
 
             sprite.color = new_color.into();
         }
-}
+    }
 
-fn movement_instructions(mut commands: Commands) {
+    pub fn movement_instructions(mut commands: Commands) {
         commands
             .spawn((
                 StateBound(Tutorial::MovementInstructions),
@@ -624,9 +649,9 @@ fn movement_instructions(mut commands: Commands) {
                     },
                 ));
             });
-}
+    }
 
-fn pause_instructions(mut commands: Commands) {
+    pub fn pause_instructions(mut commands: Commands) {
         commands
             .spawn((
                 StateBound(Tutorial::PauseInstructions),
@@ -664,23 +689,5 @@ fn pause_instructions(mut commands: Commands) {
                     },
                 ));
             });
-}
-
-/// print when either an `AppState` transition or a `TutorialState` transition happens
-fn log_transitions(
-    mut transitions: EventReader<StateTransitionEvent<AppState>>,
-    mut tutorial_transitions: EventReader<StateTransitionEvent<TutorialState>>,
-) {
-    for transition in transitions.read() {
-        info!(
-            "transition: {:?} => {:?}",
-            transition.before, transition.after
-        );
-    }
-    for transition in tutorial_transitions.read() {
-        info!(
-            "tutorial transition: {:?} => {:?}",
-            transition.before, transition.after
-        );
     }
 }

examples/ecs/sub_states.rs

@@ -9,6 +9,8 @@
 
 use bevy::prelude::*;
 
+use ui::*;
+
 #[derive(Debug, Clone, Copy, Default, Eq, PartialEq, Hash, States)]
 enum AppState {
     #[default]
@@ -61,62 +63,6 @@ fn main() {
         .run();
 }
 
-#[derive(Resource)]
-struct MenuData {
-    button_entity: Entity,
-}
-
-const NORMAL_BUTTON: Color = Color::srgb(0.15, 0.15, 0.15);
-const HOVERED_BUTTON: Color = Color::srgb(0.25, 0.25, 0.25);
-const PRESSED_BUTTON: Color = Color::srgb(0.35, 0.75, 0.35);
-
-fn setup(mut commands: Commands) {
-    commands.spawn(Camera2dBundle::default());
-}
-
-fn setup_menu(mut commands: Commands) {
-    let button_entity = commands
-        .spawn(NodeBundle {
-            style: Style {
-                // center button
-                width: Val::Percent(100.),
-                height: Val::Percent(100.),
-                justify_content: JustifyContent::Center,
-                align_items: AlignItems::Center,
-                ..default()
-            },
-            ..default()
-        })
-        .with_children(|parent| {
-            parent
-                .spawn(ButtonBundle {
-                    style: Style {
-                        width: Val::Px(150.),
-                        height: Val::Px(65.),
-                        // horizontally center child text
-                        justify_content: JustifyContent::Center,
-                        // vertically center child text
-                        align_items: AlignItems::Center,
-                        ..default()
-                    },
-                    image: UiImage::default().with_color(NORMAL_BUTTON),
-                    ..default()
-                })
-                .with_children(|parent| {
-                    parent.spawn(TextBundle::from_section(
-                        "Play",
-                        TextStyle {
-                            font_size: 40.0,
-                            color: Color::srgb(0.9, 0.9, 0.9),
-                            ..default()
-                        },
-                    ));
-                });
-        })
-        .id();
-    commands.insert_resource(MenuData { button_entity });
-}
-
 fn menu(
     mut next_state: ResMut<NextState<AppState>>,
     mut interaction_query: Query<
@@ -145,13 +91,6 @@ fn cleanup_menu(mut commands: Commands, menu_data: Res<MenuData>) {
     commands.entity(menu_data.button_entity).despawn_recursive();
 }
 
-fn setup_game(mut commands: Commands, asset_server: Res<AssetServer>) {
-    commands.spawn(SpriteBundle {
-        texture: asset_server.load("branding/icon.png"),
-        ..default()
-    });
-}
-
 const SPEED: f32 = 100.0;
 fn movement(
     time: Res<Time>,
@@ -218,7 +157,83 @@ fn clear_state_bound_entities<S: States>(
     }
 }
 
-fn setup_paused_screen(mut commands: Commands) {
+/// print when an `AppState` transition happens
+fn log_transitions(mut transitions: EventReader<StateTransitionEvent<AppState>>) {
+    for transition in transitions.read() {
+        info!(
+            "transition: {:?} => {:?}",
+            transition.before, transition.after
+        );
+    }
+}
+
+mod ui {
+    use crate::*;
+
+    #[derive(Resource)]
+    pub struct MenuData {
+        pub button_entity: Entity,
+    }
+
+    pub const NORMAL_BUTTON: Color = Color::srgb(0.15, 0.15, 0.15);
+    pub const HOVERED_BUTTON: Color = Color::srgb(0.25, 0.25, 0.25);
+    pub const PRESSED_BUTTON: Color = Color::srgb(0.35, 0.75, 0.35);
+
+    pub fn setup(mut commands: Commands) {
+        commands.spawn(Camera2dBundle::default());
+    }
+
+    pub fn setup_menu(mut commands: Commands) {
+        let button_entity = commands
+            .spawn(NodeBundle {
+                style: Style {
+                    // center button
+                    width: Val::Percent(100.),
+                    height: Val::Percent(100.),
+                    justify_content: JustifyContent::Center,
+                    align_items: AlignItems::Center,
+                    ..default()
+                },
+                ..default()
+            })
+            .with_children(|parent| {
+                parent
+                    .spawn(ButtonBundle {
+                        style: Style {
+                            width: Val::Px(150.),
+                            height: Val::Px(65.),
+                            // horizontally center child text
+                            justify_content: JustifyContent::Center,
+                            // vertically center child text
+                            align_items: AlignItems::Center,
+                            ..default()
+                        },
+                        image: UiImage::default().with_color(NORMAL_BUTTON),
+                        ..default()
+                    })
+                    .with_children(|parent| {
+                        parent.spawn(TextBundle::from_section(
+                            "Play",
+                            TextStyle {
+                                font_size: 40.0,
+                                color: Color::srgb(0.9, 0.9, 0.9),
+                                ..default()
+                            },
+                        ));
+                    });
+            })
+            .id();
+        commands.insert_resource(MenuData { button_entity });
+    }
+
+    pub fn setup_game(mut commands: Commands, asset_server: Res<AssetServer>) {
+        commands.spawn(SpriteBundle {
+            texture: asset_server.load("branding/icon.png"),
+            ..default()
+        });
+    }
+
+    pub fn setup_paused_screen(mut commands: Commands) {
         commands
             .spawn((
                 StateBound(IsPaused::Paused),
@@ -262,14 +277,5 @@ fn setup_paused_screen(mut commands: Commands) {
                         ));
                     });
             });
-}
-
-/// print when an `AppState` transition happens
-fn log_transitions(mut transitions: EventReader<StateTransitionEvent<AppState>>) {
-    for transition in transitions.read() {
-        info!(
-            "transition: {:?} => {:?}",
-            transition.before, transition.after
-        );
     }
 }