//! What a scene contains, as the tools see it.
//!
//! The renderer knows an entity has a mesh and a transform, which is enough
//! to draw it and nothing like enough to *list* it: a row in the outliner
//! needs a name, an icon and a category to tint it by. [`SceneObject`] is how
//! a kind of thing says those, and [`SceneItem`] is what marks one instance
//! of it in the world.
//!
//! One module per kind of object, and each one owns the whole of its kind --
//! the data, the components, the systems that gather it, and the
//! [`SceneObject`] implementation that says how it appears in a list. A light
//! is not "some fields in `light.rs` plus an entry in a registry somewhere
//! else"; it is [`lights`].
pub use Category;
pub use ;