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Make a bouncy ball

Make a ball bounce off a ramp toward the corner of the room. 

In this tutorial, you’ll create a ball that bounces off a ramp and toward the corner of the room. Eventually, you’ll build a block tower that the ball will crash into, but first you need to get that ball rolling.

As you complete these steps, you’ll learn how to create new 3D shapes, apply custom materials, and implement physics in your scene. 

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

Overview

The first step in creating a bouncing ball is adding a simple sphere in the scene. 

Unity provides you with a number of primitive shapes that you can add, including a sphere, a cube, a cylinder, a capsule, and even a flat plane. These simple shapes can be used as building blocks and as placeholders for more complex models. 

Here, you'll create a sphere and rename it “Ball”, which will later bounce off a ramp.


 window, right-click in an empty area and select 

 When you create the sphere, it may appear in a seemingly random location, which is actually based on the object you last framed in the 

 view. You might not even see the sphere after creating it. Don’t worry about its location for now! 



Create and rename a sphere

The ball is currently way too big — you need to make it smaller.



 determines the size of an object. In Unity, scale is relative to real-world measurements, where 1 unit typically equals 1 meter. 

Adjusting the scale of the ball to 0.25 in all dimensions makes it about the size of a standard kid’s ball — about one quarter of a meter in diameter, which is just less than one foot wide.


 You can also select the chain link icon next to the 

 When this is enabled, changing one scale property automatically changes the other two by the same amount.

Edit the sphere’s scale

Now you’re going to position the ball high above the floor near the window so that it can fall to the ground and bounce toward the corner. 

Rather than using the Transform tools in the 

 view to drag the ball around, you’ll enter the ball’s precise position directly in the 

 component. 

Every single GameObject in the scene has a 

 component, which controls its position, rotation, and scale. 

The 

 values are measured in meters along each of the 3 axes (X, Y, and Z) relative to the origin of the scene.


X = 2 will position the ball 2 meters to the right of the origin on the X-axis. 

Y = 3 will position the ball 3 meters up from the origin on the Y-axis. 

Z = -1 will position the ball 1 meter back from the origin on the Z-axis.

  You can tell which direction is positive for each axis by looking at the 

 view gizmo. The colored cones point toward the positive direction for each axis. 

Position the ball in the air

The sphere primitive you added for the ball has a default material that is a very dull gray color — if it’s a kid’s ball, it should be more exciting!



 define the visual appearance of objects in Unity. Here, you'll create a new material in your project’s assets and apply it to the sphere. 


, and name it “My Materials”. 

This is where you’ll keep your custom materials.



 then rename the new material “Ball_Mat” (short for “Ball Material”). 

You have just created a new asset in the 

 window, which means that this material can be used in any scene in your entire project. You’ve added a new custom asset! You can see from the 

 menu when you right-clicked that you can make all kinds of assets, including scripts, animations, fonts, and more. 



 view, which should make it turn the default plain white material color.



  Remember to save your scene often with 

Create and apply a new material

With your custom material now applied to the ball, you’re ready to adjust the material’s properties to your liking. You can customize the ball’s color and how it interacts with light in the scene. Creating materials can get very complicated, so you’ll start by adjusting just three key properties:

 property, select the white color swatch and use the 

 window to choose a new color. 

Observe how your changes affect the ball's appearance.



Adjust the material properties

Now that your ball looks ready for action, it's time to bring it to life by simulating physics. 

To give the ball physical properties, you'll add a 

 component, the ball will stay at its current location in midair. But with a 

 component, it will have mass and respond to gravity.


 to enter Play mode and watch as your ball floats in midair. Select the 

 window, then enter "Rigidbody" in the search bar and select the 

  Enter Play mode again and watch as your ball now responds to gravity and falls to the ground, then exit Play mode.



 mode whenever you’re done testing. While you’re in Play mode, no edits you make will be saved.



Add a Rigidbody and test

Your bouncy ball's bounce is probably pretty disappointing. It behaves more like a bag of sand than a lively, bouncy ball. 

To make it bounce, you'll create and apply a Physics Material. Unlike standard materials, which control the visual aspects of GameObjects, 

 govern the physical behavior of GameObjects, like how they bounce upon impact. 


 Rename the new material "Ball_Physics".



  Drag and drop the Physics Material onto the ball in the 

 view. 

You won't be able to tell from the 

 view that you've successfully applied the new Physics Material until you test it.



 button and watch as your ball bounces.



Create and apply a Physics Material

You have customized this ball a lot at this point. 

In this step, let's take a moment to review all of the components that contribute to the ball's behavior and appearance in Unity. 


 component sets the position, rotation, and scale of the ball. This is the only component that is required for every GameObject. 



 component determines the shape of your GameObject. A mesh is a wireframe 3D model. In the case of the ball, the Mesh is set to a Sphere shape.



 component controls the external appearance of the ball. Try to find the material you applied to the ball. When you apply a material, it shows up in this component.



component defines the physical boundaries of GameObjects for collision purposes. Try to find the 

 component integrates the ball into Unity’s physics system, giving it properties like mass and drag. 

Review the components

In this step, you'll add a ramp that the ball can bounce off. 

The ramp has to be positioned precisely beneath the ball, which can be tricky if you’re viewing the scene from an angle. You'll see how to use framing to help with this.


 prefab into your scene and place it on the floor, approximately beneath the ball. 



 to frame it, then switch to the top view using the 

 tool, adjust the ramp's position so it's directly under the ball. 



 tool, rotate the ramp so that the ball will bounce and roll to the back right corner of the room.



 mode to test the interaction. Notice the unexpected result where the ball passes through the ramp, then exit Play mode.

Before moving on, try to guess why the ball did what it did. Is there a type of component that could fix this? 

Add a Ramp and test collision

You'll now fix the ramp by adding a collider component, which is essential for physical interactions in Unity. A collider is a component that defines the shape of an object for the purpose of physical collisions and interactions within the environment. Without a collider, an object has no physical boundaries and other objects can go right through it — like a cloud.

The sphere primitive you added earlier for the ball already came with a Sphere collider — that's what the Physics Material is attached to.

Unity provides various collider shapes (such as sphere, cube, and capsule colliders). However, since the ramp has an irregular shape, you’ll use something called a 

 collider, which conforms to the unique shape of the object’s mesh (3D shape). 


 and search for 'Mesh collider'. Add the 

 property simplifies the collider into a convex shape, almost as if you were wrapping the object in some hard material. Unity needs 

 to allow them to interact with other objects.



, enter Play mode to test the ball's interaction with the ramp. 



Add a Collider to the ramp

Congratulations on making a ball bounce around your room in an interesting way! 

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

Describe the default characteristics of a primitive.

Explain the attributes a material adds to a GameObject.

Assign a material to a GameObject by dragging it from the 

Change the basic properties of a material.

Make a new Physics Material in the project window.

Explain the attributes a Physics Material adds to a GameObject.

Proceed to the next tutorial where you'll add a tower of blocks for the ball to knock over!

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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Primitive and placeholder objects

Materials introduction

Use components

Rigidbody component reference

Create and apply a custom Physic Material

Introduction to collision

Games

Film

Automotive

Explain how primitives are typically used in a 3D Scene.

Describe the types of primitives available in Unity.

Import a premade asset into a project as a GameObject.

Add a GameObject to a Scene by dragging it from the Project window.

2.1 Define GameObject.

2.2 Explain how primitives are typically used in a 3D Scene.

2.3 Describe the types of primitives available in Unity.

2.4 Add a primitive to a 3D Scene.

2.5 Define Sprite

2.6 Import a Sprite into a Scene

2.7 Create an empty Sprite

2.8 Assign an image to an empty Sprite.

2.9 Import a premade asset into a project as a GameObject.

2.10 Add a GameObject to a Scene by dragging it from the Project window.

2.11 Add a GameObject to a Scene by dragging it from the Project window.

2.12 Create an empty GameObject.

Create GameObjects

Create and assign a Material

Change the Sprite Tint color

Control the appearance of GameObjects

Veronica Brown

 Implement basic physics for GameObjects 

Apply RigidBody or RigidBody 2D components in order to enable GameObjects to act under the control of physics

Modify the basic properties of a RigidBody or RigidBody 2D component in order to control how the GameObject is affected by physics, including its mass, its drag, and the Scene's gravity

Unity Version 6.0