EditorSceneManager

Sealed editor-time extension of SceneManager that adds scene opening/closing, SceneGraph asset persistence, Build Settings synchronization, and play mode scene management.

Definition

Namespace: Paragon.Core.SceneManagement.Editor Assembly: Paragon.Editor.dll

public sealed class EditorSceneManager : SceneManager

Inheritance: SceneManager → EditorSceneManager

Remarks

EditorSceneManager bridges the runtime SceneManager with Unity's editor scene APIs. It is initialized via [InitializeOnLoadMethod] and provides:

• Scene open/close with dependency chain support — OpenScene() and CloseScene() can traverse SceneNode dependencies

• SceneGraph persistence — The graph is stored at ProjectSettings/SceneGraph.asset using InternalEditorUtility serialization (not a standard Unity asset)

• Build Settings sync — ApplySceneGraphToBuildSettings() keeps EditorBuildSettings.scenes in sync with the graph

• Play mode management — On entering play mode, the current active scene is saved to EditorPrefs and restored via RuntimeInitialize after the "Main" scene loads

The class fires SceneOpened and SceneClosed events (editor-only) that wrap Unity's internal scene lifecycle callbacks. Scenes not found in the SceneGraph trigger a warning but are still handled gracefully.

Quick Lookup

Goal	How
Open a scene in editor	EditorSceneManager.OpenScene(scene)
Open scene with dependencies	EditorSceneManager.OpenScene(scene, openDependencies: true)
Close a scene	EditorSceneManager.CloseScene(scene)
Check if scene is open	EditorSceneManager.IsSceneOpened(scene)
Get all opened scenes	EditorSceneManager.GetOpenedScenes()
Get all project scenes	EditorSceneManager.GetAllScenesInProject()
Get the SceneGraph	EditorSceneManager.GetSceneGraph()
Save graph to disk	EditorSceneManager.SaveSceneGraphAsset()
Sync Build Settings	EditorSceneManager.ApplySceneGraphToBuildSettings()

Events

SceneOpened

public static event Action<Scene> SceneOpened;

Fired when a scene is opened in the editor. The Scene parameter may be null if the opened scene is not in the SceneGraph.

SceneClosed

public static event Action<Scene> SceneClosed;

Fired when a scene is closed in the editor. The Scene parameter may be null if the closed scene is not in the SceneGraph.

Methods

OpenScene

Opens a scene in the editor, optionally loading its dependency chain first.

public static void OpenScene(Scene scene, bool openDependencies = false, OpenSceneMode openSceneMode = OpenSceneMode.SINGLE)

Parameter	Type	Default	Description
scene	Scene	—	Scene to open
openDependencies	bool	false	Load dependency chain scenes first
openSceneMode	OpenSceneMode	SINGLE	SINGLE replaces all; ADDITIVE adds alongside

When openDependencies is true, dependency scenes are opened first in ADDITIVE mode regardless of the initial openSceneMode, then the target scene is opened with the specified mode.

CloseScene

Closes a scene in the editor, optionally closing its dependency chain.

public static void CloseScene(Scene scene, bool closeDependencies = false)

Parameter	Type	Default	Description
scene	Scene	—	Scene to close
closeDependencies	bool	false	Also close dependency chain scenes

GetOpenedScenes

Returns all SceneGraph scenes currently open in the editor.

public static IEnumerable<Scene> GetOpenedScenes()

Returns: Scenes from the graph that are currently loaded and valid.

IsSceneOpened

Checks if a scene is currently loaded in the editor.

public static bool IsSceneOpened(Scene scene)

GetAllScenesInProject

Scans the Assets folder for all .scene files, regardless of whether they're in the SceneGraph.

public static IEnumerable<Scene> GetAllScenesInProject()

GetSceneGraph

Gets the current SceneGraph, loading or creating it as needed.

public static SceneGraph GetSceneGraph()

Returns: The singleton SceneGraph instance. Creates a new one if none exists.

LoadSceneGraphAsset

Loads the SceneGraph from ProjectSettings/SceneGraph.asset.

public static SceneGraph LoadSceneGraphAsset()

SaveSceneGraphAsset

Saves the current SceneGraph to ProjectSettings/SceneGraph.asset.

public static void SaveSceneGraphAsset()

ApplySceneGraphToBuildSettings

Syncs EditorBuildSettings.scenes to match the SceneGraph scene list.

public static void ApplySceneGraphToBuildSettings()

SaveCurrentModifiedScenesIfUserWantsTo

Prompts the user to save modified scenes. Wraps Unity's built-in dialog.

public static bool SaveCurrentModifiedScenesIfUserWantsTo()

Returns: true if the user saved or discarded changes; false if cancelled.

Common Pitfalls

SceneGraph is NOT a regular asset The SceneGraph is stored in ProjectSettings/SceneGraph.asset using InternalEditorUtility.SaveToSerializedFileAndForget(). It will not appear in the Project window. Use GetSceneGraph() to access it.

Scenes not in SceneGraph trigger warnings Opening or closing scenes that aren't in the graph logs a warning. This is expected for editor-only scenes but may indicate missing graph entries for runtime scenes.

Play mode start scene is the "Main" scene UpdatePlayModeStartScene() sets playModeStartScene to the scene named "Main" when any scene from the graph is active. If no scene named "Main" exists, play mode uses the current scene.

See Also

• SceneGraphEditor — Custom Inspector that uses EditorSceneManager for persistence and sync

• SceneGraphBuildProcessor — Build processor that injects the graph into builds

• Internals/SceneHierarchyWindow — Used to expand scenes in Hierarchy during play mode