Add touch feedback effect on background

src/effects/mod.rs

@@ -4,6 +4,8 @@ use crate::sun_system::{Sun, Satellite, Level};
 use crate::collision::{FatalCollisionEvent, HitBox};
 mod red_star;
 mod gravity_viz;
+mod selection_glow;
+mod touch_feedback;
 
 #[derive(Resource)]
 struct SunFlameConfig {
@@ -37,6 +39,8 @@ pub(super) fn plugin(app: &mut App) {
     app.add_systems(Update, (update_and_render_swallow_fx).in_set(GameplaySystem));
     red_star::plugin(app);
     gravity_viz::plugin(app);
+    selection_glow::plugin(app);
+    touch_feedback::plugin(app);
 }
 
 fn draw_sun_flames(
@@ -184,6 +188,4 @@ fn update_and_render_swallow_fx(
             commands.entity(e).despawn();
         }
     }
-}
-
-
+}

src/effects/touch_feedback.rs

@@ -0,0 +1,67 @@
+use bevy::prelude::*;
+use bevy::input::touch::{TouchInput, TouchPhase};
+use crate::GameplaySystem;
+
+pub fn plugin(app: &mut App) {
+    app.add_systems(Update, (spawn_touch_feedback, update_touch_feedback).in_set(GameplaySystem));
+}
+
+#[derive(Component)]
+struct TouchFeedback {
+    elapsed: f32,
+    duration: f32,
+}
+
+fn spawn_touch_feedback(
+    mut commands: Commands,
+    mut er_touch: EventReader<TouchInput>,
+    camera_query: Query<(&Camera, &GlobalTransform)>,
+    window_q: Query<&Window>,
+) {
+    let Ok((camera, cam_gt)) = camera_query.single() else { return; };
+    let Ok(_window) = window_q.single() else { return; };
+
+    for touch in er_touch.read() {
+        // Only create feedback on touch start
+        if touch.phase == TouchPhase::Started {
+            // Convert screen position to world position
+            if let Ok(world_pos) = camera.viewport_to_world_2d(cam_gt, touch.position) {
+                commands.spawn((
+                    TouchFeedback {
+                        elapsed: 0.0,
+                        duration: 0.5,
+                    },
+                    Transform::from_translation(world_pos.extend(0.0)),
+                ));
+            }
+        }
+    }
+}
+
+fn update_touch_feedback(
+    mut commands: Commands,
+    mut gizmos: Gizmos,
+    mut query: Query<(Entity, &mut TouchFeedback, &Transform)>,
+    time: Res<Time>,
+) {
+    for (entity, mut feedback, transform) in query.iter_mut() {
+        feedback.elapsed += time.delta_secs();
+        let t = (feedback.elapsed / feedback.duration).clamp(0.0, 1.0);
+
+        // Expanding circle effect
+        let radius = 2.0 + t * 8.0; // Expands from 2.0 to 10.0
+        let alpha = (1.0 - t).powf(2.0); // Fades out
+
+        // Cyan/blue color for touch feedback
+        let color = Color::srgb(0.3, 0.9, 1.0).with_alpha(0.7 * alpha);
+
+        let position = transform.translation.truncate();
+        let iso = Isometry2d::from_translation(position);
+        gizmos.circle_2d(iso, radius, color);
+
+        // Despawn when animation is complete
+        if feedback.elapsed >= feedback.duration {
+            commands.entity(entity).despawn();
+        }
+    }
+}