Method insert

perro_source/runtime_project/perro_runtime/src/cns/node_arena.rs:153–184

Insert a node and return its current slot/generation id. Reuses a free slot when available. Otherwise appends a new slot.

(&mut self, node: SceneNode)

pub(crate) struct ScopedNodeMut<'a> {
    arena: &'a mut NodeArena,
    index: usize,
    armed: bool,
}

impl ScopedNodeMut<'_> {
    /// End a normally classified callback. Unwind before this call leaves the
    /// guard armed so drop invalidates every dependent domain.
    #[inline]
    pub(crate) fn finish(mut self) {
        self.armed = false;
    }
}

impl Deref for ScopedNodeMut<'_> {
    type Target = SceneNode;

    fn deref(&self) -> &Self::Target {
        self.arena.nodes[self.index]
            .as_ref()
            .expect("scoped node slot stays live while borrowed")
    }
}

impl DerefMut for ScopedNodeMut<'_> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        self.arena.nodes[self.index]
            .as_mut()
            .expect("scoped node slot stays live while borrowed")
    }
}

impl Drop for ScopedNodeMut<'_> {
    fn drop(&mut self) {
        if self.armed {
            self.arena.bump_world_state_revisions();