diff --git a/crates/bevy_ecs/src/hierarchy.rs b/crates/bevy_ecs/src/hierarchy.rs index 276746f50b..c5d9aa8d29 100644 --- a/crates/bevy_ecs/src/hierarchy.rs +++ b/crates/bevy_ecs/src/hierarchy.rs @@ -139,6 +139,96 @@ impl FromWorld for ChildOf { #[doc(alias = "IsParent")] pub struct Children(Vec); +impl Children { + /// Swaps the child at `a_index` with the child at `b_index`. + #[inline] + pub fn swap(&mut self, a_index: usize, b_index: usize) { + self.0.swap(a_index, b_index); + } + + /// Sorts children [stably](https://en.wikipedia.org/wiki/Sorting_algorithm#Stability) + /// in place using the provided comparator function. + /// + /// For the underlying implementation, see [`slice::sort_by`]. + /// + /// For the unstable version, see [`sort_unstable_by`](Children::sort_unstable_by). + /// + /// See also [`sort_by_key`](Children::sort_by_key), [`sort_by_cached_key`](Children::sort_by_cached_key). + #[inline] + pub fn sort_by(&mut self, compare: F) + where + F: FnMut(&Entity, &Entity) -> core::cmp::Ordering, + { + self.0.sort_by(compare); + } + + /// Sorts children [stably](https://en.wikipedia.org/wiki/Sorting_algorithm#Stability) + /// in place using the provided key extraction function. + /// + /// For the underlying implementation, see [`slice::sort_by_key`]. + /// + /// For the unstable version, see [`sort_unstable_by_key`](Children::sort_unstable_by_key). + /// + /// See also [`sort_by`](Children::sort_by), [`sort_by_cached_key`](Children::sort_by_cached_key). + #[inline] + pub fn sort_by_key(&mut self, compare: F) + where + F: FnMut(&Entity) -> K, + K: Ord, + { + self.0.sort_by_key(compare); + } + + /// Sorts children [stably](https://en.wikipedia.org/wiki/Sorting_algorithm#Stability) + /// in place using the provided key extraction function. Only evaluates each key at most + /// once per sort, caching the intermediate results in memory. + /// + /// For the underlying implementation, see [`slice::sort_by_cached_key`]. + /// + /// See also [`sort_by`](Children::sort_by), [`sort_by_key`](Children::sort_by_key). + #[inline] + pub fn sort_by_cached_key(&mut self, compare: F) + where + F: FnMut(&Entity) -> K, + K: Ord, + { + self.0.sort_by_cached_key(compare); + } + + /// Sorts children [unstably](https://en.wikipedia.org/wiki/Sorting_algorithm#Stability) + /// in place using the provided comparator function. + /// + /// For the underlying implementation, see [`slice::sort_unstable_by`]. + /// + /// For the stable version, see [`sort_by`](Children::sort_by). + /// + /// See also [`sort_unstable_by_key`](Children::sort_unstable_by_key). + #[inline] + pub fn sort_unstable_by(&mut self, compare: F) + where + F: FnMut(&Entity, &Entity) -> core::cmp::Ordering, + { + self.0.sort_unstable_by(compare); + } + + /// Sorts children [unstably](https://en.wikipedia.org/wiki/Sorting_algorithm#Stability) + /// in place using the provided key extraction function. + /// + /// For the underlying implementation, see [`slice::sort_unstable_by_key`]. + /// + /// For the stable version, see [`sort_by_key`](Children::sort_by_key). + /// + /// See also [`sort_unstable_by`](Children::sort_unstable_by). + #[inline] + pub fn sort_unstable_by_key(&mut self, compare: F) + where + F: FnMut(&Entity) -> K, + K: Ord, + { + self.0.sort_unstable_by_key(compare); + } +} + impl<'a> IntoIterator for &'a Children { type Item = ::Item;