Version: 2019.1
public void AddRemap (AssetImporter.SourceAssetIdentifier identifier, Object externalObject);

Parameters

identifierThe identifier of the sub-asset.
externalObjectThe object to be mapped to the internal object. Can belong to another Prefab or Asset, but not the Asset that is being changed.

Description

Map a sub-asset from an imported asset (such as an FBX file) to an external Asset of the same type.

Apply changes by writing the metadata and reimporting the Asset. Instances of the Asset automatically use the mapped object once you have reimported the Asset.

If the type of the external asset does not match the type of the sub-asset, or if the reference is null, instances of the Asset will continue to use the internal asset without producing an error.

using UnityEngine;
using UnityEditor;

public class Extractor { public static void ExtractFromAsset(Object subAsset, string destinationPath) { string assetPath = AssetDatabase.GetAssetPath(subAsset);

var clone = Object.Instantiate(subAsset); AssetDatabase.CreateAsset(clone, destinationPath);

var assetImporter = AssetImporter.GetAtPath(assetPath); assetImporter.AddRemap(new AssetImporter.SourceAssetIdentifier(subAsset), clone);

AssetDatabase.WriteImportSettingsIfDirty(assetPath); AssetDatabase.ImportAsset(assetPath, ImportAssetOptions.ForceUpdate); } }