[Solved] Creating Prefab Variant with script

Hello,

I've looked into the PrefabUtility class, it doesn't seem to provide any useful method to do so.

I also tried by script to instantiate a variant prefab, modifying it and then making it a prefab again, it doesn't keep the "base prefab" attribute in the inspector (it does if you do that in the editor and choose to create a 'new original Prefab' when making a prefab from the instantiated gameobject).


Thanks

Edit: Solved

 

The API is a bit more raw than the Editor workflows.

To create a new Variant, use SaveAsPrefabAsset on a Prefab instance. This will have that instance as its base.
To create a new original Prefab Variant based on an existing Variant, which uses the same base as that Variant, first use UnpackPrefabInstance on an instance of the existing Variant, then call SaveAsPrefabAsset on the unpacked instance.

You can use those workflows in the Editor as well, the dialog boxes just provide some shortcuts which performs those multiple steps for you.

 

Code (CSharp):

1.  
2. Object source = Resources.Load(prefabPath);
3. GameObject objSource = (GameObject)PrefabUtility.InstantiatePrefab(source);
4. GameObject obj = PrefabUtility.SaveAsPrefabAsset(objSource, variantAssetPath);

works like a charm ! ( I was using GameObject.Instantiate((GameObject)source) instead of InstantiatePrefab ).

I probably won't need it anymore, but.. I wasn't able to find the SaveAsPrefabInstance method in the PrefabUtility class (version : Unity 2018.2.0x-ImprovedPrefabs).

Thanks.

 

Glad it worked! And yeah, I forgot to mention that you need to instantiate with InstantiatePrefab which is the editor way of instantiating Prefabs as opposed to instantiating Prefabs at runtime. Also, the SaveAsPrefabInstance was a typo; I meant SaveAsPrefabAsset. I corrected it above.

 

Creating a Prefab Variant this way, when creating it from a fbx file returns null in 2019.1.8f1.
Would it be possible to have a dedicated method that always work?

 

I've found that AssetDatabase.LoadAssetAtPath<>() fixed my issue.

 

Thank you for this! Our project manager did not want to create a "Resources" folder so I was able to do the same using:

Code (CSharp):

1. Object originalPrefab = (GameObject)AssetDatabase.LoadAssetAtPath(prefabPath, typeof(GameObject));
2. GameObject objSource = PrefabUtility.InstantiatePrefab(originalPrefab) as GameObject;    
3. GameObject prefabVariant = PrefabUtility.SaveAsPrefabAsset(objSource, localPath);

Using Unity 2019.2.9