Guid References

Package for Unity that provides functionality to reference GameObjects based on Guid (Global Unique IDentifier).

Supports UPM (Unity Package Manager).

Inspired by https://github.com/Unity-Technologies/guid-based-reference.

Installation

Install via git url by adding this entry in your manifest.json

"com.sag.guid-references": "https://github.com/STARasGAMES/Guid-References.git#upm"

Explanation

Unity provides easy to use and convenient solution to reference components through inspector. But it has limitation that this components have to be in the same scene.

Having a way to identify game object by some unique identifier (GUID) opens a lot of opportunities:

• cross-scene references
• reference game object that is not loaded/created yet
• create save system based on GUIDs

Basic usage

1. Add GuidComponent to you game object. In the inspector you should see this component with auto-generated Guid. The system guarantees this Guid to be unique.

2. Then in your script create GuidReference serializable field:

public GuidReference guidReference;

3. Drag and drop game object with GuidComponent into the GuidReference field.

4. Use GuidReference in your script.

void Update()
{
  if (guidReference.gameObject != null) // this check is needed in case referenced game object is not loaded yet.
    guidReference.gameObject.transform.Rotate(0, 10, 0);
}

Advanced usage

Make use of events

Every frame check that reference is not NULL is a waste of resources. Alternatively, we can use events Added and Removed to populate and clear reference:

public GuidReference guidReference;
private GameObject cachedReferencedGameObject;

void Awake()
{
  guidReference.Added += go => cachedReferencedGameObject = go;
  guidReference.Removed += () => cachedReferencedGameObject = null;
}

Manually resolve reference

Also, you can resolve references by yourself in case you don't want to use GuidReference:

private System.Guid customGuid; // you need to provide your own Guid to resolve reference.

void Initialize()
{
  var referencedGameObject = GuidManagerSingleton.ResolveGuid(customGuid);
}

There is version of GuidManagerSingleton.ResolveGuid() with onAdded and onRemoved callbacks.

GuidManager class

GuidManagerSingleton is just an API-interface over IGuidManager interface. The default implementation is GuidManager class. GuidManagerSingleton used by GuidComponent and GuidReference classes.

If you want to use DI you need to explicitly set guid manager instance, but be careful:

IGuidManager guidManager = new GuidManager();
...
GuidManagerSingleton.SetInstance(guidManager);