Can we get individualized userData please?

Unity Engine
, ,
2

Hi @Yoraiz0r !

I had a read through your post and I can see you hit a lot of walls along the way, sorry to hear that!

Since reading this post, I tried 2 different approaches (one of them failed and the 2nd one seems like it could work).

The first failed approach was to use a SerializedObject and try to wrap a Texture in it, such that I could Add a property to it. There’s no AddProperty method to SerializedObject, but CopyFromSerializedProperty does exist and I tried adding a new serialized property that way. I had it compiling, and then when I ran it I got the error:
Destination property could not be found

Which means that a new property can’t be applied, which is a bit of a downer.

So, anyways, I looked through the codebase and found we could do something with the following APIs:

  1. AssetImporter.AddRemap
  2. AssetImporter.GetExternalObjectMap

The idea here, is to add a reference to another object, such that we could load the object if needed (and the object could be anything we want, like a ScriptableObject or a Texture).

I’ve got some code working here, where we can add a reference to a texture for a specific Model:

public class ExternalReferenceTest
{
    [MenuItem("AssetDatabase/VerifyExternalReferences")]
    public static void VerifyExternalReferences()
    {
        var texturePath = "Assets/test.png";
        var texture = AssetDatabase.LoadAssetAtPath<Texture2D>(texturePath);

        var fbxPath = "Assets/coloredCube.fbx";

        var allFbxAssets = AssetDatabase.LoadAllAssetsAtPath(fbxPath);

        var fbxImporter = (ModelImporter)AssetImporter.GetAtPath(fbxPath);

        var textureCounter = 0;
        var externalReferences = fbxImporter.GetExternalObjectMap();
        foreach (var curRef in externalReferences)
        {
            if (curRef.Value is Texture2D)
            {
                Debug.Log($"Found reference to {curRef.Value.name}");
                textureCounter++;
            }
        }

        if(textureCounter == 0)
            Debug.Log("Found no textures");

        fbxImporter.AddRemap(new AssetImporter.SourceAssetIdentifier(texture), texture);
        fbxImporter.SaveAndReimport();

        externalReferences = fbxImporter.GetExternalObjectMap();
        foreach (var curRef in externalReferences)
        {
            if(curRef.Value is Texture2D)
                Debug.Log($"Found reference to {curRef.Value.name}");
        }
    }
}

If you look at the corresponding .meta file (in my case coloredCube.fbx.meta) you’ll notice that the externalObjects array has been populated. For example, it would look like this:

ModelImporter:
  serializedVersion: 22200
  internalIDToNameTable: []
  externalObjects:
  - first:
      type: UnityEngine:Texture2D
      assembly: UnityEngine.CoreModule
      name: test
    second: {fileID: 2800000, guid: d38ec503f07e72140b7fa54c8abed249, type: 3}

This way we can add extra typed data to your objects, without having to mess with the userData.

Does this help?