Setting up the Game

Moving the Player

Moving the Camera

Setting up the Play Area

Creating Collectibles

Detecting Collisions with Collectibles

Displaying Score and Text

Adding AI Navigation

Building the Game

Welcome to 3D Beginner: Roll-a-Ball Game! In this learning project, you’ll:  

Use Unity Editor and its built-in capabilities to set up a simple game environment

Write your own custom scripts to create the game functionality

Create a basic user interface to improve the game experience

Build your game, so other people can play it!

3D Beginner: Roll-a-Ball Game

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Overview

Create a collectible GameObject

Rotate the PickUp GameObject

Make PickUp a Prefab

Add more collectibles

Final script sample

Unity_RollABall_5-4.mp4

Unity_RollABall_5-2.mp4

Unity_RollABall_5-3_2022_LTS_Update.mp4

Unity_RollABall_5-1_2022_LTS_Update.mp4

5.2.final-pickups-duplicated.mp4

5.2.2-pickup-rotating.mp4

5.4.3-duplicating-pickups_changed.mp4

Create a PickUp GameObject for the player to collect

Instantiate the Prefab around your play area

Create_a_collectible_GameObject-Transcript.txt

Rotate_the_PickUp_GameObject-Transcript.txt

Make_PickUp_a_Prefab-Transcript.txt

Add_more_collectibles-Transcript.txt

Unit 2 - Program a basic game

By the end of this tutorial, your game will look something like this:

Follow the video or text instructions below to create a PickUp GameObject, set the PickUp GameObject’s Transform values, and create a PickUp material:

In the Hierarchy window, right-click > 3D Object > Cube, then rename it “PickUp”.

Reset the PickUp GameObject’s Transform component. 

Press the F key to frame in on the PickUp GameObject in the Scene view. 

Use the Move tool to drag the PickUp GameObject out of the way so it’s not overlapping with the Player GameObject.


2.  Set the PickUp Gameobject’s Transform values.

Set the PickUp Gameobject’s Position Y value to 0.5 to raise it above the Ground GameObject.

Set each of the Rotation axis values to 45 to tilt it on an angle.

Set each of the Scale axis values to 0.5 to make it smaller. 


In the Project window, find and select the Background material.

In the main menu, go to Edit > Duplicate. Alternatively, you can press Ctrl+D (macOS: Cmd+D).

With the Pickup material still selected in the Project window, use the color picker to change its base map color property.

Set the RGB values 255, 200, and 0 for a bright yellow. 

Drag the PickUp material from the Project window onto the PickUp GameObject in the Scene view.

The PickUp GameObject is selected as a small yellow rotated cube in the scene. The yellow PickUp material is highlighted in the Project window and the Transform component is highlighted in the Inspector window.

Follow the video or text instructions below to create a new Rotator script and rotate the PickUp GameObject in the Update function:

With the PickUp GameObject selected in the Hierarchy window, select Add Component > New script in the Inspector window. 

In the Project window, move the script from the root Assets folder into the Scripts folder. 

2.  Rotate the PickUp GameObject in the Update function.

With the Rotator script open, remove the Start function — you won’t need it.

After the opening curly brace of the Update function, add the following line of code:

transform.Rotate (new Vector3 (15, 30, 45) * Time.deltaTime);

The Rotator script is highlighted in the Project window and is shown as an added script component on the PickUp GameObject in the Inspector window. 

Follow the video or text instructions below to turn the PickUp GameObject into a prefab, then enter and exit prefab editing mode:

1.  Turn the PickUp GameObject into a prefab. 

In the Assets folder, right-click > Create > Folder, then rename this new folder “Prefabs”. 

Drag the PickUp GameObject from the Hierarchy window into the Prefabs folder.

Select the arrow to the right of the PickUp GameObject in the Hierarchy window to open prefab editing mode. 

To return to the normal Scene view, select the back arrow at the top of the Hierarchy window.


The PickUp GameObject is dragged from the Hierarchy window into the Project window to make it into a prefab. The small arrow to the right of the PickUp GameObject is highlighted, which leads to prefab editing mode. 

Follow the video or text instructions below to make an empty parent GameObject for the pickups, align to a top view of the scene, place duplicate pickups around the scene, and test your game:

1.  Make an empty parent GameObject for the PickUp GameObjects.

In the Hierarchy window, create a new empty GameObject and name it “PickUp Parent”.

In the Hierarchy window, drag the PickUp GameObject onto the PickUp Parent GameObject.


Important:  Before beginning this step, set the tool handles in the Scene view to Global coordinates rather than Local. With Global coordinates, the Scene view tools will always point in the same directions, regardless of how the selected object is rotated. This will make it easier to move the Pickups straight along the X and Z planes.

Select the Gizmo in the upper right of the Scene view to switch to a top-down view. 

Zoom out a little so you can see the entire play area.


3.  Place duplicate pickups around the scene.

Move the first PickUp GameObject somewhere you like.

With the PickUp GameObject selected, duplicate it with Ctrl+D (macOS: Cmd+D).

Use the Move tool to relocate the second instance of the prefab. 

Repeat this process to place as many PickUp GameObjects as you like in the scene.


When you test your game, you will notice that the PickUp GameObjects are still acting like solid obstacles. You’ll fix that in the next tutorial.

The Global coordinate system selected from the dropdown in the Scene view.

If your script is not working as expected, below is an example of what your code should look like at this point. The comments have been added to make the code more readable. 


using UnityEngine;

public class Rotator : MonoBehaviour
{

 // Update is called once per frame
 void Update()
    {
 // Rotate the object on X, Y, and Z axes by specified amounts, adjusted for frame rate.
        transform.Rotate (new Vector3 (15, 30, 45) * Time.deltaTime);
    }
 
}

Creating Collectibles

1. Overview

2. Create a collectible GameObject

3. Rotate the PickUp GameObject

4. Make PickUp a Prefab

5. Add more collectibles

6. Final script sample

Complete this tutorial