Root Node & init_root

.gitignore

@@ -1,4 +1,5 @@
 /target
 .DS_Store
 assets/.DS_Store
-.VSCodeCounter
+.VSCodeCounter
+.idea

src/configuration.rs

@@ -110,6 +110,8 @@ pub trait VoxelWorldConfig: Resource + Default + Clone {
     fn init_custom_materials(&self) -> bool {
         true
     }
+
+    fn init_root(&self, mut _commands: Commands, _root: Entity) {}
 }
 
 #[derive(Resource, Clone, Default)]

src/voxel_world_internal.rs

@@ -61,9 +61,15 @@ pub(crate) struct NeedsMaterial<C>(PhantomData<C>);
 
 pub(crate) struct Internals<C>(PhantomData<C>);
 
-impl<C: VoxelWorldConfig> Internals<C> {
+#[derive(Component)]
+pub struct WorldRoot<C>(PhantomData<C>);
+
+impl<C: VoxelWorldConfig> Internals<C>
+where
+    C: VoxelWorldConfig,
+{
     /// Init the resources used internally by bevy_voxel_world
-    pub fn setup(mut commands: Commands) {
+    pub fn setup(mut commands: Commands, configuration: Res<C>) {
         commands.init_resource::<ChunkMap<C>>();
         commands.init_resource::<ChunkMapInsertBuffer<C>>();
         commands.init_resource::<ChunkMapUpdateBuffer<C>>();
@@ -72,16 +78,30 @@ impl<C: VoxelWorldConfig> Internals<C> {
         commands.init_resource::<MeshCacheInsertBuffer<C>>();
         commands.init_resource::<ModifiedVoxels<C>>();
         commands.init_resource::<VoxelWriteBuffer<C>>();
+
+        // Create the root node and allow to modify it by the configuration.
+        let world_root = commands
+            .spawn((
+                WorldRoot::<C>(PhantomData),
+                VisibilityBundle::default(),
+                TransformBundle::default(),
+            ))
+            .id();
+        configuration.init_root(commands, world_root)
     }
 
     /// Find and spawn chunks in need of spawning
     pub fn spawn_chunks(
         mut commands: Commands,
         mut chunk_map_write_buffer: ResMut<ChunkMapInsertBuffer<C>>,
+        world_root: Query<Entity, With<WorldRoot<C>>>,
         chunk_map: Res<ChunkMap<C>>,
         configuration: Res<C>,
         camera_info: CameraInfo<C>,
     ) {
+        // Panic if no root exists as it is already inserted in the setup.
+        let world_root = world_root.get_single().unwrap();
+
         let (camera, cam_gtf) = camera_info.single();
         let cam_pos = cam_gtf.translation().as_ivec3();
 
@@ -159,7 +179,9 @@ impl<C: VoxelWorldConfig> Internals<C> {
             let has_chunk = ChunkMap::<C>::contains_chunk(&chunk_position, &chunk_map_read_lock);
 
             if !has_chunk {
-                let chunk = Chunk::<C>::new(chunk_position, commands.spawn(NeedsRemesh).id());
+                let chunk_entity = commands.spawn(NeedsRemesh).id();
+                commands.entity(world_root).add_child(chunk_entity);
+                let chunk = Chunk::<C>::new(chunk_position, chunk_entity);
 
                 chunk_map_write_buffer.push((chunk_position, ChunkData::with_entity(chunk.entity)));