Add support for selecting multiple entities

bevy_editor_panes/bevy_3d_viewport/src/selection_box.rs

@@ -1,6 +1,6 @@
 use bevy::ecs::system::SystemParam;
 use bevy::prelude::*;
-use bevy_editor_core::selection::SelectedEntity;
+use bevy_editor_core::selection::EditorSelection;
 use bevy_render::primitives::Aabb;
 
 #[derive(SystemParam)]
@@ -68,7 +68,7 @@ fn draw_fallback_selection_box(gizmos: &mut Gizmos, global_transform: &GlobalTra
 
 pub fn selection_box_system(
     show: Res<ShowSelectionBox>,
-    selected_entity: Res<SelectedEntity>,
+    selection: Res<EditorSelection>,
     mut gizmos: Gizmos,
     queries: SelectionBoxQueries,
     meshes: Res<Assets<Mesh>>,
@@ -77,25 +77,23 @@ pub fn selection_box_system(
         return;
     }
 
-    let Some(entity) = selected_entity.0 else {
-        return;
-    };
-
-    // Calculate the bounding box for the entity (including children)
-    if let Some(world_aabb) = calculate_world_aabb(
-        entity,
-        &queries.mesh_query,
-        &queries.sprite_query,
-        &queries.aabb_query,
-        &queries.children_query,
-        &queries.transform_query,
-        &meshes,
-    ) {
-        draw_selection_box(&mut gizmos, &world_aabb);
-    } else {
-        // Fallback to simple transform-based selection box
-        if let Ok(global_transform) = queries.transform_query.get(entity) {
-            draw_fallback_selection_box(&mut gizmos, global_transform);
+    for entity in selection.iter() {
+        // Calculate the bounding box for the entity (including children)
+        if let Some(world_aabb) = calculate_world_aabb(
+            entity,
+            &queries.mesh_query,
+            &queries.sprite_query,
+            &queries.aabb_query,
+            &queries.children_query,
+            &queries.transform_query,
+            &meshes,
+        ) {
+            draw_selection_box(&mut gizmos, &world_aabb);
+        } else {
+            // Fallback to simple transform-based selection box
+            if let Ok(global_transform) = queries.transform_query.get(entity) {
+                draw_fallback_selection_box(&mut gizmos, global_transform);
+            }
         }
     }
 }

bevy_editor_panes/bevy_properties_pane/src/lib.rs

@@ -8,7 +8,7 @@ use bevy::{
     reflect::*,
     scene2::{CommandsSpawnScene, Scene, SceneList, bsn},
 };
-use bevy_editor_core::prelude::*;
+use bevy_editor_core::{prelude::*, selection::common_conditions::primary_selection_changed};
 use bevy_pane_layout::prelude::*;
 
 /// Plugin for the editor properties pane.
@@ -19,8 +19,7 @@ impl Plugin for PropertiesPanePlugin {
         app.register_pane("Properties", setup_pane).add_systems(
             Update,
             update_properties_pane.run_if(
-                resource_changed::<SelectedEntity>
-                    .or(any_match_filter::<Added<PropertiesPaneBody>>),
+                primary_selection_changed.or(any_match_filter::<Added<PropertiesPaneBody>>),
             ),
         );
     }
@@ -50,23 +49,23 @@ fn setup_pane(pane: In<PaneStructure>, mut commands: Commands) {
 
 fn update_properties_pane(
     pane_bodies: Query<Entity, With<PropertiesPaneBody>>,
-    selected_entity: Res<SelectedEntity>,
+    selection: Res<EditorSelection>,
     world: &World,
     mut commands: Commands,
 ) {
     for pane_body in &pane_bodies {
         commands.entity(pane_body).despawn_children();
         commands
-            .spawn_scene(properties_pane(&selected_entity, world))
+            .spawn_scene(properties_pane(&selection, world))
             .insert(Node::default())
             .insert(ChildOf(pane_body));
     }
 }
 
-fn properties_pane(selected_entity: &SelectedEntity, world: &World) -> impl Scene {
-    match selected_entity.0 {
-        Some(selected_entity) => bsn! {Node { flex_direction: FlexDirection::Column } [
-            {component_list(selected_entity, world)}
+fn properties_pane(selection: &EditorSelection, world: &World) -> impl Scene {
+    match selection.primary() {
+        Some(selection) => bsn! {Node { flex_direction: FlexDirection::Column } [
+            {component_list(selection, world)}
         ]}
         .boxed_scene(),
         None => bsn! {

bevy_editor_panes/bevy_scene_tree/src/lib.rs

@@ -1,9 +1,7 @@
 //! An interactive, collapsible tree view for hierarchical ECS data in Bevy.
 
 use bevy::{app::Plugin, color::palettes::tailwind, prelude::*};
-use bevy_editor_core::selection::{
-    SelectedEntity, common_handlers::toggle_select_on_click_for_entity,
-};
+use bevy_editor_core::selection::EditorSelection;
 use bevy_i_cant_believe_its_not_bsn::{Template, TemplateEntityCommandsExt, on, template};
 use bevy_pane_layout::prelude::{PaneAppExt, PaneStructure};
 
@@ -36,8 +34,8 @@ fn setup_pane(pane: In<PaneStructure>, mut commands: Commands) {
             BackgroundColor(tailwind::NEUTRAL_600.into()),
         ))
         .observe(
-            |mut trigger: On<Pointer<Click>>, mut selected_entity: ResMut<SelectedEntity>| {
-                selected_entity.0 = None;
+            |mut trigger: On<Pointer<Click>>, mut selection: ResMut<EditorSelection>| {
+                selection.clear();
                 trigger.propagate(false);
             },
         );
@@ -46,24 +44,37 @@ fn setup_pane(pane: In<PaneStructure>, mut commands: Commands) {
 fn update_scene_tree(
     scene_trees: Query<Entity, With<SceneTreeRoot>>,
     scene_entities: Query<(Entity, &Name)>,
-    selected_entity: Res<SelectedEntity>,
+    selection: Res<EditorSelection>,
     mut commands: Commands,
 ) {
     for scene_tree in &scene_trees {
         let tree_rows: Template = scene_entities
             .iter()
-            .flat_map(|(entity, name)| scene_tree_row_for_entity(entity, name, &selected_entity))
+            .flat_map(|(entity, name)| scene_tree_row_for_entity(entity, name, &selection))
             .collect();
 
         commands.entity(scene_tree).build_children(tree_rows);
     }
 }
 
-fn scene_tree_row_for_entity(
-    entity: Entity,
-    name: &Name,
-    selected_entity: &SelectedEntity,
-) -> Template {
+fn scene_tree_row_for_entity(entity: Entity, name: &Name, selection: &EditorSelection) -> Template {
+    let selection_handler =
+        move |mut trigger: On<Pointer<Click>>,
+              keyboard_input: Res<ButtonInput<KeyCode>>,
+              mut selection: ResMut<EditorSelection>| {
+            if trigger.button != PointerButton::Primary {
+                return;
+            }
+
+            trigger.propagate(false);
+            let ctrl = keyboard_input.any_pressed([KeyCode::ControlLeft, KeyCode::ControlRight]);
+            if ctrl {
+                selection.toggle(entity);
+            } else {
+                selection.set(entity);
+            }
+        };
+
     template! {
         {entity}: (
             Node {
@@ -72,9 +83,9 @@ fn scene_tree_row_for_entity(
                 ..Default::default()
             },
             BorderRadius::all(Val::Px(4.0)),
-            BackgroundColor(if selected_entity.0 == Some(entity) { tailwind::NEUTRAL_700.into() } else { Color::NONE }),
+            BackgroundColor(if selection.contains(entity) { tailwind::NEUTRAL_700.into() } else { Color::NONE }),
         ) => [
-            on(toggle_select_on_click_for_entity(entity));
+            on(selection_handler);
             (
                 Text(name.into()),
                 TextFont::from_font_size(11.0),

crates/bevy_editor/src/lib.rs

@@ -27,7 +27,7 @@ pub use bevy;
 use bevy::winit::{UpdateMode, WinitSettings};
 use bevy_context_menu::ContextMenuPlugin;
 use bevy_editor_core::EditorCorePlugin;
-use bevy_editor_core::selection::common_handlers::toggle_select_on_click;
+use bevy_editor_core::selection::Selectable;
 use bevy_editor_styles::StylesPlugin;
 
 // Panes
@@ -130,14 +130,13 @@ fn dummy_setup(
         Name::new("Circle"),
     ));
 
-    commands
-        .spawn((
-            Mesh3d(meshes.add(Plane3d::new(Vec3::Y, Vec2::splat(1.5)))),
-            MeshMaterial3d(materials_3d.add(Color::WHITE)),
-            Name::new("Plane"),
-            Pickable::default(),
-        ))
-        .observe(toggle_select_on_click);
+    commands.spawn((
+        Mesh3d(meshes.add(Plane3d::new(Vec3::Y, Vec2::splat(1.5)))),
+        MeshMaterial3d(materials_3d.add(Color::WHITE)),
+        Name::new("Plane"),
+        Pickable::default(),
+        Selectable,
+    ));
 
     commands.spawn((
         DirectionalLight {

crates/bevy_editor_core/src/lib.rs

@@ -12,7 +12,7 @@ use crate::{actions::ActionsPlugin, selection::SelectionPlugin, utils::CoreUtils
 pub mod prelude {
     pub use crate::{
         actions::{ActionAppExt, ActionWorldExt},
-        selection::SelectedEntity,
+        selection::EditorSelection,
         utils::IntoBoxedScene,
     };
 }