Is there any way to list subassets in a main asset without loading all subassets?
I can load all subassets using AssetDatabase.LoadAllAssetsAtPath() but that might be too slow. I just want to get the names of all subassets in a given asset to generate an unique name for a new subasset. Do anyone have better ideas?
No. They do have functions called AssetDatabase.IsSubAsset and AssetDatabase.IsMainAsset. You might try AssetDatabase.AddObjectToAsset, and you would know what I meant.