A singleton that manages the unique identifiers of all resources within a project. Resource UIDs (Unique IDentifiers) allow the engine to keep references between resources intact, even if files can renamed or moved. They can be accessed with [code]uid://[/code]. [ResourceUID] keeps track of all registered resource UIDs in a project, generates new UIDs, and converts between their string and integer representations. Adds a new UID value which is mapped to the given resource path. Fails with an error if the UID already exists, so be sure to check [method has_id] beforehand, or use [method set_id] instead. Generates a random resource UID which is guaranteed to be unique within the list of currently loaded UIDs. In order for this UID to be registered, you must call [method add_id] or [method set_id]. Returns the path that the given UID value refers to. Fails with an error if the UID does not exist, so be sure to check [method has_id] beforehand. Returns whether the given UID value is known to the cache. Converts the given UID to a [code]uid://[/code] string value. Removes a loaded UID value from the cache. Fails with an error if the UID does not exist, so be sure to check [method has_id] beforehand. Updates the resource path of an existing UID. Fails with an error if the UID does not exist, so be sure to check [method has_id] beforehand, or use [method add_id] instead. Extracts the UID value from the given [code]uid://[/code] string. The value to use for an invalid UID, for example if the resource could not be loaded. Its text representation is [code]uid://<invalid>[/code].