Loading Issue in v0.0.11

[thombruce]

Due to systems ordering, if the player visits the credits before starting the game a star will be spawned. If they return to the main menu and start the game, the game will crash.

Good time to get systems to execute in a proper order and remove the dependency on schedule parameters.

[thombruce]

Good documentation: https://bevyengine.org/news/bevy-0-10/

[thombruce]

Two simple tricks help us out here:

1. .chain() will execute the systems in the order they are listed
2. The special apply_deferred system enforces a buffer which means our entities are properly loaded by triggering the next system

Neither solved the problem alone, but together they do. Useful for loading things in a certain order, but as the documentation says... be careful not to overuse as this will cause bottlenecks. There are probably refactoring steps I can take in the actual systems. This has been hastily added to correct for a bug identified in a release.

    fn build(&self, app: &mut App) {
        app.add_plugins(OrbitPlugin);
        // TODO: Having some real trouble with ordering systems
-       app.add_systems(OnExit(AppState::StartMenu), spawn_star);
-       app.add_systems(OnEnter(AppState::GameCreate), spawn_planets);
-       app.add_systems(OnExit(AppState::GameCreate), spawn_demo_orbital);
+       app.add_systems(
+           OnEnter(AppState::GameCreate),
+           (
+               spawn_star,
+               apply_deferred,
+               spawn_planets,
+               apply_deferred,
+               spawn_demo_orbital,
+           )
+               .chain(),
+       );
        app.add_systems(Update, animate_sprite.run_if(in_state(AppState::Active)));
    }

[thombruce]

Resolved as of d97a90877b0e7293e197df8ae9a48f82ab392d85. Release of v0.0.12 to follow shortly.