All content in this course uses:

Build a stable structure from primitive shapes while learning how colliders and prefabs affect your scene.

Make a tower of prefab blocks

Use new primitive shapes to build a balanced structure, learning about colliders and prefabs. 

In this tutorial, you’ll create a few block towers that your bouncing ball will be able to knock over.

When you’re ready to get started, go to the next step.

Overview

You’re about to begin the construction of your block tower. 

To make your first building block, you’ll start by adding a primitive cube. Just like you did with the sphere, you’ll add it to the scene, rename it, then reset its position to the origin as a starting point.

However, this time you’ll use a new technique for creating the new 3D object and a new technique for resetting the object’s position. 


 

This technique gets you to the same menu as right-clicking an empty area in the 

 properties, including resetting its position to the origin (0,0,0). 

This should position the cube in the center of the room, halfway sunk into the floor.

Add a block and reset its Transform

In this step, you’ll reposition the block so that it’s in the path of the ball and edit its scale so that it looks more like a classic kid’s building block.

However, rather than editing the scale in the 

 component directly like you did with the ball, you’ll actually use the 

 tool, you’ll have mastered the three most important tools in the 

 tool to reposition the cube above the floor where it will get hit by the ball. 



 tool and use the X, Y, and Z handles to scale it down so it’s a tall, skinny block that the ball can knock over. You can confirm in the 

 tools using the W, E, and R keyboard shortcuts in the 

 view for a clearer look and make sure that it’s sitting just above the floor.

Remember, you can always undo any unwanted edits with 

 mode to see the ball unable to knock over the block, which is something you’ll fix in the next step



Reposition and scale the block

 GameObject. 

Initially, the block won’t move when hit by the ball, acting like an immovable brick wall. This behavior is due to the lack of a 

 component, which governs the physics properties of the GameObject. 

With a 

 component, the block can react to a collision and fall over. 


 mode to test the interaction. 

Observe that the block now gets knocked over when hit by the ball. 



  Remember to save your scene often with 

Add Rigidbody Component

 GameObject, which you've already enhanced with a 

 in Unity are GameObjects, with all their components and properties already set up, that you can reuse as a template. You can keep these custom prefabs in a folder in the 

 and name the new folder “My Prefabs”.



 button or by right-clicking in an empty space in the 

 window, it converts the object into a prefab.

Observe that the block in the 

 window turns blue, indicating it is a copy — or an 

Create a Block Prefab

Now you’ll use the block prefab you created to build a small tower in your Unity scene. The process of constructing a tower not only tests your ability to use prefabs efficiently, but it also allows you to experiment with object positioning in Unity. 



 The tower doesn’t need to be perfect! As long as it stands up, it'll work well.  In fact, it may even be more visually interesting if it’s not perfectly aligned.


 If the "Center/Pivot" and "Global/Local" buttons aren’t visible in your editor by default, click the three vertical dots in the top-right corner of the Scene window, go to the 

 is active, your blocks will end up halfway through the floor at their pivot point.



 window into your scene, positioning them to form a tower. 



  In order to make sure your blocks are aligned, you should examine the tower from all angles. Sometimes it might look aligned from one angle, but not from another. Try framing the block you’re working with, then orbiting it or using the 

 view gizmo to examine it from different angles. 



 mode to observe how the tower behaves.



 mode and make any necessary adjustments to the position of the blocks to refine your tower's stability or design.

Create a tower from prefab blocks

You might have noticed that the ball had a hard time knocking over all those blocks. By default, the 

 component sets an object’s mass to 1.0 kilogram (kg). Your 1kg ball is trying to knock over a tower made of three 1kg blocks! 

In this step, you will reduce the weight of your 

 prefab, and in doing so, reduce the weight of every block in the scene — that’s the beauty of prefabs! 

To do this, you'll enter 

 a powerful feature in Unity that allows you to edit a prefab asset directly. Prefab editing mode isolates the prefab, enabling you to make changes without affecting the rest of your scene. 


 prefab to enter prefab editing mode. 

This mode allows you to make changes to the prefab independently of your scene. You’ll know you’re in prefab editing mode when the rest of your scene disappears from the 

 prefab in prefab editing mode, navigate to the 

  To exit prefab editing mode, select the small back arrow at the top of the 

 window. 

This action will return you to the main scene.



  After exiting prefab editing mode, test the changes by entering 

 mode. Observe how the ball can now much more easily knock over the tower. 

Remember to exit 

Reduce the weight in prefab editing mode

In this step, you'll change the block’s material using prefab editing mode so it’s not that boring gray anymore. You'll see the power of prefabs once again, as you modify a single asset and see the change instantly reflected across all instances of that prefab. 


 prefab in prefab editing mode by double-clicking it in the 

 window. 

This isolates the prefab for editing.



 property. 

This action opens a window displaying all available material assets in your entire project.



  Browse through the list of materials. You'll see various options, including some designed for furniture, floors, and so on — some of them might have some unintuitive names. Select a material that appeals to you and apply it to the Block prefab.



  You can also create your own material like you did for the ball if you don’t see one you like!



  Exit prefab editing mode by selecting the back arrow at the top of the 

 window.

Observe how the new material is now applied to all instances of the block in your scene.



  Remember to save your scene regularly with 

Add a material to the prefab

In this step, you’ll address the clutter in your Unity project's 

 prefabs. 

You'll learn to organize these blocks under a single parent GameObject, simplifying your scene and making it more manageable. 

As a reminder, a 

 GameObject is a GameObject that serves as a container for other GameObjects, known as 

 GameObjects. These terms describe a hierarchical relationship, much like a family tree.


 prefab in your list to select all blocks in between. You can also hold 

) to select individual additional GameObjects.



  Right-click the selected blocks and choose 

 

This action creates a new parent GameObject with the individual blocks indented as child GameObjects.



  Rename this new GameObject something descriptive, like “Block_Tower”. 



 GameObject selected, you can move, rotate, and scale the entire group of blocks as one unit. 

Organize blocks with a parent GameObject

The block tower you've created consists of multiple individual blocks arranged in a specific structure.

If you convert this entire structure into a prefab, you enable the possibility of reusing this complex object multiple times within your project. 

You’ll see that prefabs are particularly beneficial when creating repeated structures or patterns in your game environment.


 window, select the Block_Tower GameObject.



 prefab). 

This action converts your GameObject into a reusable prefab. 

Now, you can easily create multiple instances of your 

  Add a few more of these towers to your scene to make for a more interesting collision. 



  Enter Play mode to test the collision path with multiple towers. 



  If you want, edit the block tower in prefab editing mode to make it a more interesting structure.  

Turn the block tower into a prefab

With so many towers in your scene, the ball may once again have a hard time knocking all of the blocks over. But what would happen if the ball was ten times heavier? Or one hundred times heavier?


 component, increase the mass to ensure it topples the block structure when it collides.



  Enter Play mode and watch the blocks fly!



Adjust the ball's mass

Congratulations on creating a fun block tower experiment for the kids’ bedroom!

Here are some of the things you learned how to do along the way:

component to reposition an object at the origin.

Make a new prefab from an existing GameObject in a scene.

Switch the tool handle position of a GameObject between 

Assign a material to a GameObject by changing the 

Make an empty GameObject as a parent for other GameObjects.

Arrange GameObjects in parent-child relationships using the 

Proceed to the next tutorial where you'll edit the lighting, change the background, and position your camera for a perfect shot of your scene. 

Review and proceed to next tutorial

Identify the defaults elements in a new scene, Create and manipulate GameObjects and configure their components.

Scene Building Essentials

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Product Manager at Unity

GameObjects

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Use components

Transforms

Prefabs

Materials introduction

The Hierarchy window

Games

Film

Automotive

Explain the Toolbar buttons used to manipulate objects.

Select a GameObject from both the Hierarchy window and the Scene view.

Link GameObjects in parent-child relationships using the Hierarchy window to create complex GameObjects.

Explain the relationship between the Scene view and the Inspector window.

Move, scale, and rotate a GameObject using the Toolbar buttons and the mouse in the Scene view.

Move, scale, and rotate a GameObject using the Transform Component in the Inspector window.

Position Sprites in 3D space in a 2D Scene.

Use 3D GameObjects in a 2D Scene to group Sprites.

Versión de Unity 2022.3