button system

src/buttons.rs

@@ -0,0 +1,53 @@
+use bevy::{input_focus::InputFocus, prelude::*, sprite::Anchor};
+
+pub struct ButtonPlugin;
+
+#[derive(EntityEvent)]
+pub struct ButtonPressedEvent(Entity);
+
+#[derive(EntityEvent)]
+pub struct ButtonReleasedEvent(Entity);
+
+#[derive(Component)]
+struct ButtonPressed;
+
+impl Plugin for ButtonPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(Startup, button_setup)
+            .add_systems(Update, button_system);
+    }
+}
+
+fn button_setup(mut commands: Commands) {
+    commands.init_resource::<InputFocus>();
+}
+
+fn button_system(
+    mut input_focus: ResMut<InputFocus>,
+    interaction_query: Query<(Entity, &Interaction), Changed<Interaction>>,
+    pressed_query: Query<&ButtonPressed>,
+    mut commands: Commands,
+) {
+    for (entity, interaction) in interaction_query {
+        match *interaction {
+            Interaction::Pressed => {
+                input_focus.set(entity);
+                commands.entity(entity).insert(ButtonPressed);
+                commands.trigger(ButtonPressedEvent(entity));
+            }
+            Interaction::Hovered => {
+                input_focus.set(entity);
+                if let Ok(_) = pressed_query.get(entity) {
+                    commands.entity(entity).remove::<ButtonPressed>();
+                    commands.trigger(ButtonReleasedEvent(entity));
+                }
+            }
+            Interaction::None => {
+                if let Ok(_) = pressed_query.get(entity) {
+                    commands.entity(entity).remove::<ButtonPressed>();
+                    commands.trigger(ButtonReleasedEvent(entity));
+                }
+            }
+        }
+    }
+}

src/card/drag.rs

@@ -0,0 +1,4 @@
+use bevy::prelude::*;
+
+#[derive(Component)]
+pub struct DraggableCard;

src/card/mod.rs

@@ -1,5 +1,7 @@
 use bevy::prelude::*;
 
+pub mod drag;
+
 pub struct CardPlugin;
 
 #[derive(Component)]

src/main.rs

@@ -1,5 +1,6 @@
 use bevy::{audio::Volume, prelude::*};
 
+mod buttons;
 mod card;
 mod dev_tools;
 mod turns;
@@ -11,6 +12,7 @@ fn main() {
             turns::TurnSystemPlugin,
             card::CardPlugin,
             dev_tools::DevToolsPlugin,
+            buttons::ButtonPlugin,
         ))
         .add_systems(Startup, setup)
         .run();