khora_data/ecs/components/children.rs
1// Copyright 2025 eraflo
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use khora_core::ecs::entity::EntityId;
16use khora_macros::Component;
17
18/// A component that lists the direct children of an entity.
19///
20/// This component is typically attached to a parent entity and contains a list
21/// of all `EntityId`s that have this entity as their `Parent`. It is primarily
22/// used for traversing the scene hierarchy downwards (from parent to child).
23///
24/// Note: This component should be managed by a dedicated hierarchy maintenance
25/// system to ensure it stays in sync with `Parent` components on child entities.
26#[derive(Debug, Clone, Default, PartialEq, Eq, Component)]
27pub struct Children(pub Vec<EntityId>);