Build settings and scene order in Unity

Introduction

Build settings let you choose which scenes to include when making your game. Scene order decides which scene starts first and how the game moves between scenes.

When you want to decide which parts of your game to include in the final build.

When you want the game to start from a specific scene, like a main menu.

When you want to control the order scenes load during gameplay.

When testing different scenes without building the whole game.

When organizing your game flow from start to finish.

Syntax

Unity

1. Open Unity Editor.
2. Go to File > Build Settings.
3. In the Scenes In Build list, add scenes by dragging them or clicking 'Add Open Scenes'.
4. Arrange scenes by dragging them up or down to set the order.
5. The scene at index 0 is the first scene that loads when the game starts.

The first scene in the list (index 0) is the one Unity loads first when you run the game.

You can add or remove scenes anytime before building your game.

Examples

The game starts at MainMenu, then can load Level1 and Level2 in order.

Unity

Scenes In Build:
0: MainMenu.unity
1: Level1.unity
2: Level2.unity

The splash screen shows first, then the main menu, and settings can be loaded later.

Unity

Scenes In Build:
0: SplashScreen.unity
1: MainMenu.unity
2: Settings.unity

Sample Program

This script loads the next scene in the build order when LoadNextScene is called. It checks if there is a next scene and loads it, or logs a message if none remain.

Unity

/* This is a Unity C# script to load the next scene based on build order */
using UnityEngine;
using UnityEngine.SceneManagement;

public class SceneLoader : MonoBehaviour
{
    public void LoadNextScene()
    {
        int currentIndex = SceneManager.GetActiveScene().buildIndex;
        int nextIndex = currentIndex + 1;
        if (nextIndex < SceneManager.sceneCountInBuildSettings)
        {
            SceneManager.LoadScene(nextIndex);
        }
        else
        {
            Debug.Log("No more scenes to load.");
        }
    }
}

Important Notes

Always make sure your scenes are added to the Build Settings or they won't be included in the game.

Scene order affects how you can load scenes by build index in scripts.

You can reorder scenes anytime to change the game flow without renaming files.

Summary

Build Settings control which scenes are included in your game build.

The first scene in the list is the starting point of your game.

Scene order helps manage game flow and scene loading in scripts.

Practice

1. What does the Build Settings window in Unity control?

easy

A. Which scenes are included in the final game build

B. The resolution of the game window

C. The color scheme of the editor

D. The physics settings of the game

Solution

1. Step 1: Understand the purpose of Build Settings

   The Build Settings window lists scenes to include in the game build and their order.

2. Step 2: Identify what Build Settings controls

   It controls which scenes are packaged into the final game, not editor or physics settings.

3. Final Answer:

   Which scenes are included in the final game build -> Option A

4. Quick Check:

   Build Settings = Scenes included [OK]

Hint: Build Settings = scenes included in game build [OK]

Common Mistakes:

• Confusing Build Settings with editor appearance
• Thinking it controls physics or resolution
• Assuming it sets scene start order only

2. Which of the following is the correct way to add a scene to the build in Unity?

easy

A. Drag the scene file into the Build Settings window's Scenes In Build list

B. Right-click the scene in Project and select 'Add to Build'

C. Open the scene and press Ctrl+B

D. Rename the scene file to include 'build' in its name

Solution

1. Step 1: Recall how to add scenes to build

   In Unity, you add scenes by dragging them into the Scenes In Build list in Build Settings.

2. Step 2: Evaluate the options

   Only dragging the scene file into Build Settings is correct; other options are invalid or do nothing.

3. Final Answer:

   Drag the scene file into the Build Settings window's Scenes In Build list -> Option A

4. Quick Check:

   Add scene = drag to Build Settings [OK]

Hint: Add scenes by dragging into Build Settings list [OK]

Common Mistakes:

• Trying to add scenes by renaming files
• Using keyboard shortcuts that don't add scenes
• Expecting context menu to add scenes automatically

3. Given the following scenes in Build Settings in order: ["Menu", "Level1", "Level2"], what will SceneManager.LoadScene(1) load?

medium

A. The scene named "Menu"

B. The scene named "Level1"

C. The scene named "Level2"

D. An error because index 1 is invalid

Solution

1. Step 1: Understand scene indexing in Build Settings

   Scenes are indexed starting at 0 in the order listed in Build Settings.

2. Step 2: Identify scene at index 1

   Index 0 = "Menu", index 1 = "Level1", index 2 = "Level2".

3. Final Answer:

   The scene named "Level1" -> Option B

4. Quick Check:

   Index 1 = second scene = Level1 [OK]

Hint: Scene index starts at 0 in Build Settings [OK]

Common Mistakes:

• Assuming index 1 is the first scene
• Confusing scene names with indexes
• Thinking index 1 causes an error

4. You try to load a scene by index using SceneManager.LoadScene(3), but get an error. What is the most likely cause?

medium

A. SceneManager.LoadScene only accepts strings

B. You must use scene names, not indexes

C. The scene file is missing from the Project folder

D. The scene at index 3 is not added to Build Settings

Solution

1. Step 1: Understand scene indexing and Build Settings

   Scene indexes correspond to the order in Build Settings; index 3 means the fourth scene.

2. Step 2: Identify cause of error

   If index 3 is out of range, it means fewer than 4 scenes are added to Build Settings.

3. Final Answer:

   The scene at index 3 is not added to Build Settings -> Option D

4. Quick Check:

   Index out of range = scene missing in Build Settings [OK]

Hint: Check Build Settings scene count before loading by index [OK]

Common Mistakes:

• Thinking indexes are unrelated to Build Settings
• Believing LoadScene only accepts names
• Assuming missing file causes this specific error

5. You want your game to start with the "Intro" scene, but currently the "MainMenu" scene is first in Build Settings. How can you fix this without renaming scenes?

hard

A. Call SceneManager.LoadScene("Intro") in the first scene's script

B. Change the scene file name to "00_Intro"

C. Drag the "Intro" scene to the top of the Scenes In Build list

D. Remove "MainMenu" from Build Settings

Solution

1. Step 1: Understand scene start order in Build Settings

   The first scene in the Scenes In Build list is the one that starts when the game runs.

2. Step 2: Adjust scene order without renaming

   Drag the "Intro" scene to the top of the list to make it the first scene loaded.

3. Final Answer:

   Drag the "Intro" scene to the top of the Scenes In Build list -> Option C

4. Quick Check:

   First scene in Build Settings = start scene [OK]

Hint: First scene in Build Settings list starts game [OK]

Common Mistakes:

• Renaming files instead of reordering scenes
• Removing scenes unnecessarily
• Relying only on script calls without build order