Scene Transitions

A Scene Transition is an orchestration of load and unload operations to effectively transition between scenes, with or without an intermediate scene. For example, if you want to transition from scene A to scene B you could:

1. Load the scene B.
2. Unload the scene A.

That's only two operations, but if you want to have a loading screen as well you could:

1. Load the loading scene.
2. Load the scene B.
3. Unload the scene A.
4. Unload the loading scene.

That's four operations now. The TransitionAsync method lets you provide the scene (or scenes) you want to transition to from the current active scene and if you want an intermediate scene (loading scene for example).

The loading screen

The second argument to TransitionAsync is a LoadingScreen. Naming a scene gives you one implicitly, so the common case stays a one-liner:

MySceneManager.TransitionAsync("target", "loading");        // a scene, as before
MySceneManager.TransitionAsync("target", new MyScreen());   // a prefab or UI Toolkit document

When the loading screen is a scene, the LoadingBehavior component in it is notified with the progress. Its WaitForScriptedStart and WaitForScriptedEnd fields control whether the transition waits for an animation to start and/or end — effectively delaying the transition to display visual feedback such as a fade in/out.

Knowing where you are

When TransitionAsync is awaited, it waits until the entire transition has completed and the loading screen is gone. If you need a specific moment before that, the operation reports its phase:

SceneOperation op = MySceneManager.TransitionAsync("target", "loading");

op.StateChanged += o =>
{
  if (o.State == SceneOperationState.ScreenOut)
    BeginIntroCutscene();       // the loading screen is fully gone
};

await op;

You can also rely on the target scene's own Awake(), or subscribe to SceneLoaded on the operation or the manager.

nota

A transition always activates something — it unloads the scene you came from, so it cannot leave nothing active. If your SceneParameters does not name an index to activate, index 0 is used.