Function mark_dirty_trees 

pub fn mark_dirty_trees(
    changed_transforms: Query<'_, '_, Entity, Or<(Changed<Transform>, Changed<ChildOf>, Added<GlobalTransform>)>>,
    orphaned: RemovedComponents<'_, '_, ChildOf>,
    transforms: Query<'_, '_, &mut TransformTreeChanged>,
    parents: Query<'_, '_, &ChildOf>,
    static_optimizations: ResMut<'_, StaticTransformOptimizations>,
)

Optimization for static scenes.

Propagates a “dirty bit” up the hierarchy towards ancestors. Transform propagation can ignore entire subtrees of the hierarchy if it encounters an entity without the dirty bit.

Configure behavior with StaticTransformOptimizations.