Fix missing pub export on systems

Export publicly the asset and component system to allow an app to
manually add them.

CHANGELOG

@@ -3,6 +3,12 @@
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Fixed
+
+- Fix missing public export of `component_animator_system()` and `asset_animator_system()` preventing the animation of all but the built-in items.
+
 ## [0.3.0] - 2022-01-28
 
 ### Added

README.md

@@ -10,9 +10,9 @@ Tweening animation plugin for the Bevy game engine.
 
 ## Features
 
-- [x] Versatile customizable lens system to animate any field of any component or asset.
-- [x] Sequence of tweening animations chained together, running one after the other, to create complex animations.
-- [x] Multiple tweening animations per component, running in parallel, to animate different fields with different parameters.
+- [x] Animate any field of any component or asset, including custom ones.
+- [x] Run multiple tweens (animations) per component/asset in parallel.
+- [x] Chain multiple tweens (animations) one after the other for complex animations.
 
 ## Usage
 

src/lib.rs

@@ -119,7 +119,7 @@ pub use lens::{
     ColorMaterialColorLens, Lens, SpriteColorLens, TextColorLens, TransformPositionLens,
     TransformRotationLens, TransformScaleLens, UiPositionLens,
 };
-pub use plugin::TweeningPlugin;
+pub use plugin::{asset_animator_system, component_animator_system, TweeningPlugin};
 
 /// How should this easing loop repeat
 #[derive(Clone, Copy)]

src/plugin.rs

@@ -2,7 +2,32 @@ use bevy::{asset::Asset, ecs::component::Component, prelude::*};
 
 use crate::{Animator, AnimatorState, AssetAnimator};
 
-/// Plugin to add systems related to tweening
+/// Plugin to add systems related to tweening of common components and assets.
+///
+/// This plugin adds systems for a predefined set of components and assets, to allow their
+/// respective animators to be updated each frame:
+/// - [`Transform`]
+/// - [`Text`]
+/// - [`Style`]
+/// - [`Sprite`]
+/// - [`ColorMaterial`]
+///
+/// This ensures that all predefined lenses work as intended, as well as any custom lens
+/// animating the same component or asset type.
+///
+/// For other components and assets, including custom ones, the relevant system needs to be
+/// added manually by the application:
+/// - For components, add [`component_animator_system::<T>`] where `T: Component`
+/// - For assets, add [`asset_animator_system::<T>`] where `T: Asset`
+/// 
+/// This plugin is entirely optional. If you want more control, you can instead add manually
+/// the relevant systems for the exact set of components and assets actually animated.
+///
+/// [`Transform`]: https://docs.rs/bevy/0.6.0/bevy/transform/components/struct.Transform.html
+/// [`Text`]: https://docs.rs/bevy/0.6.0/bevy/text/struct.Text.html
+/// [`Style`]: https://docs.rs/bevy/0.6.0/bevy/ui/struct.Style.html
+/// [`Sprite`]: https://docs.rs/bevy/0.6.0/bevy/sprite/struct.Sprite.html
+/// [`ColorMaterial`]: https://docs.rs/bevy/0.6.0/bevy/sprite/struct.ColorMaterial.html
 #[derive(Debug, Clone, Copy)]
 pub struct TweeningPlugin;
 
@@ -16,6 +41,10 @@ impl Plugin for TweeningPlugin {
     }
 }
 
+/// Animator system for components.
+///
+/// This system extracts all components of type `T` with an `Animator<T>` attached to the same entity,
+/// and tick the animator to animate the component.
 pub fn component_animator_system<T: Component>(
     time: Res<Time>,
     mut query: Query<(&mut T, &mut Animator<T>)>,
@@ -31,6 +60,9 @@ pub fn component_animator_system<T: Component>(
     }
 }
 
+/// Animator system for assets.
+///
+/// This system ticks all `AssetAnimator<T>` components to animate their associated asset.
 pub fn asset_animator_system<T: Asset>(
     time: Res<Time>,
     mut assets: ResMut<Assets<T>>,