A ScriptableObject is a data container that you can use to save large amounts of data, independent of class instances. One of the main use cases for ScriptableObjects is to reduce your project’s memory usage by avoiding copies of values. This is useful if your project has a prefabAn asset type that allows you to store a GameObject complete with components and properties. The prefab acts as a template from which you can create new object instances in the scene. More info
See in Glossary that stores unchanging data in attached MonoBehaviour scriptsA piece of code that allows you to create your own Components, trigger game events, modify Component properties over time and respond to user input in any way you like. More info
See in Glossary.
Every time you instantiate that prefab, it will get its own copy of that data. Instead of using this method and storing duplicated data, you can use a ScriptableObject to store the data and then access it by reference from all the prefabs. This means that there is one copy of the data in memory.
Just like MonoBehaviours, ScriptableObjects derive from the base UnityEngine.Object but, unlike MonoBehaviours, you can’t attach a ScriptableObject to a GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary. Instead, you need to save them as Assets in your Project.
When you use the Unity Editor, you can save data to ScriptableObjects while editing and at runtime because ScriptableObjects use the Editor namespace and Editor scripting. In a deployed build, however, you can’t use ScriptableObjects to save data, but you can use the saved data from the ScriptableObject Assets that you set up during development.
When you save data from Editor Tools to ScriptableObjects as an asset, Unity writes the data to disk and it persists between sessions.
This page provides an overview of the ScriptableObject class and its common uses when scripting with it. For a complete reference of every member of the ScriptableObject class, refer to the ScriptableObject script reference.
The main use cases for ScriptableObjects are:
A ScriptableObject must inherit from the ScriptableObject class.
To create a new ScriptableObject script, do one of the following:
You can use the CreateAssetMenu attribute to create custom assets using your class. For example:
using UnityEngine;
[CreateAssetMenu(fileName = "Data", menuName = "ScriptableObjects/SpawnManagerScriptableObject", order = 1)]
public class SpawnManagerScriptableObject : ScriptableObject
{
public string prefabName;
public int numberOfPrefabsToCreate;
public Vector3[] spawnPoints;
}
With the previous script in your AssetsAny media or data that can be used in your game or project. An asset may come from a file created outside of Unity, such as a 3D Model, an audio file or an image. You can also create some asset types in Unity, such as an Animator Controller, an Audio Mixer or a Render Texture. More info
See in Glossary folder, you can create an instance of your ScriptableObject by navigating to Assets > Create > ScriptableObjects > SpawnManagerScriptableObject. Give your new ScriptableObject instance a meaningful name and alter the values. To use these values, you need to create a new script that references your ScriptableObject, in this case, a SpawnManagerScriptableObject. For example:
using UnityEngine;
public class Spawner : MonoBehaviour
{
// The GameObject to instantiate.
public GameObject entityToSpawn;
// An instance of the ScriptableObject defined above.
public SpawnManagerScriptableObject spawnManagerValues;
// This will be appended to the name of the created entities and increment when each is created.
int instanceNumber = 1;
void Start()
{
SpawnEntities();
}
void SpawnEntities()
{
int currentSpawnPointIndex = 0;
for (int i = 0; i < spawnManagerValues.numberOfPrefabsToCreate; i++)
{
// Creates an instance of the prefab at the current spawn point.
GameObject currentEntity = Instantiate(entityToSpawn, spawnManagerValues.spawnPoints[currentSpawnPointIndex], Quaternion.identity);
// Sets the name of the instantiated entity to be the string defined in the ScriptableObject and then appends it with a unique number.
currentEntity.name = spawnManagerValues.prefabName + instanceNumber;
// Moves to the next spawn point index. If it goes out of range, it wraps back to the start.
currentSpawnPointIndex = (currentSpawnPointIndex + 1) % spawnManagerValues.spawnPoints.Length;
instanceNumber++;
}
}
}
Note: The script file must have the same name as the class.
Attach the previous script to a GameObject in your SceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary. Then, in the InspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
See in Glossary, set the Spawn Manager Values field to the new SpawnManagerScriptableObject that you set up.
Set the Entity To Spawn field to any prefab in your Assets folder, then click Play in the Editor. The prefab you referenced in the Spawner instantiates using the values you set in the SpawnManagerScriptableObject instance.
If you’re working with ScriptableObject references in the Inspector, you can double click the reference field to open the Inspector for your ScriptableObject. You can also create a custom Editor to define the look of the Inspector for your type to help manage the data that it represents.