What is in this mission?

Explore the sample scene

Set up the scanner

Code the scanning functionality

Balloon Inflator

Escape Room project overview

Number pad

Keycard reader

Sliding Door

Mission 4 Quiz - Custom VR Development

Project 3: Clone with a twist! 

Submit your final project

Clone with a twist!

Learn to write scripts for advanced interactions in VR applications, and create your own unique VR project.

In the previous missions, you used pre-made interaction scripts provided to you as part of the Create with VR project. This mission will teach you to write scripts specifically for VR applications. You’ll write these scripts from scratch in the context of three separate projects.

In project 1, the XRI example scene created by the XR Interaction Toolkit team, you'll reference existing code and documentation to program some more advanced, customized interactables.

In project 2, you’ll follow guidelines from a project brief to create part of a VR escape room. Rather than following step-by-step instructions here, you’ll only receive hints.

In project 3, which you’ll submit to receive your pathway badge, you’ll create your own unique VR project. The challenge here is to create a clone with a twist: a version of an established VR experience, but with a unique alteration.

, you should already have a good foundational knowledge of scripting in the Unity engine to make the most out of this learning content.

If you don’t already have a foundational understanding of scripting, now is an excellent time to learn. We recommend you complete the 

If you feel almost ready but want to brush up on a few skills without doing the entire Junior Programmer pathway, why not check out the 

Custom VR Development

Unity VR Development

Dive into the world of virtual reality with Unity's VR Development Pathway. Learn to design immersive experiences, build VR games, and master Unity's VR tools. Start creating in VR today!

VR Development Pathway - Learn Unity VR Game Development | Unity Learn

 or have the equivalent experience, before starting Unity VR Development.

In addition, basic coding experience is recommended before starting the Custom VR Development mission, which can be obtained via the 

Ready to develop for VR? This guided learning Pathway will prepare you for a job in the VR industry!

Welcome to VR Development! This learning pathway is designed for anyone interested in learning to create experiences for VR. This pathway assumes a basic knowledge of Unity and basic knowledge of programming.

VR Development

Welcome to the VR Pathway

VR Software Setup

1.1 - VR Project Setup

1.2 - VR Locomotion

1.3 - Grabbable Objects

1.4 - Sockets

Challenge 1 - Architecture Review

The VR software landscape

Lab 1 - VR Personal Project Basics

Submission 1 - Share your Work

Mission 1 Quiz - VR Basics 

VR Software Setup 

Mission 1 Quiz 1 - VR Basics

Learn the basics of setting up a VR project and implementing simple interactivity like locomotion and grabbing objects.

In this mission, you will learn the basics of setting up a VR project and implementing simple interactivity.

In these tutorials, you will do the following:

Set up a VR-ready project with the room of your choice

Implement locomotion so that users can move around the scene

Add grabbable objects users can pick up and throw around

Set up sockets that objects can snap into

In the Challenge for this mission, you will apply your skills in an architectural review prototype. Then, in the Lab, you'll fill out a design document to lay out a concept for your own project, and then begin working on it. Finally, in the Quiz, you will test your new knowledge.

VR Basics

2.1 - Audio and Haptics

2.2 - Activation Events

2.3 - Direct and Ray Interactors

2.4 - User Interface

Challenge 2 - 3D Painting

The XR hardware landscape

Lab 2 - Personal Project Events & Interactions

Submission 2 - Share your Work

Mission 2 Quiz - VR Events & Interactions

Learn how to implement more complex interactions in VR to make the experience more immersive, such as audio, haptics, and user interfaces.

In this mission, you will implement more complex interactions in VR to make the experience more immersive.

Apply new functionality to specific objects

Allow the user to toggle between multiple types of interactors

In the Challenge for this mission, you will apply your skills in a 3D painting prototype. Then, in the Lab, you'll implement the core functionality of your personal project. Finally, in the Quiz, you will test your new knowledge.

Events and Interactions

3.1 - Comfort and Accessibility

3.2 - Optimization

3.3 - Lighting

3.4 - Building and Sharing

Challenge 3 - Training Simulation

Keeping up with XR technology

Lab 3 - Personal Project Ergonomics & Optimization

Submission 3 - Share your Work

Mission 3 Quiz - VR Ergonomics & Optimization

Explore ergonomics and optimization for VR for making apps as accessible and comfortable as possible.

In this mission, you will focus on ergonomics and optimization for VR in order to make your app as accessible and comfortable as possible.In these tutorials, you will do the following:

In the Challenge for this mission, you will apply your skills in an industrial training simulation prototype. Then, in the Lab, you'll implement the core functionality of your personal project. Finally, in the Quiz, you will test your new knowledge.

Ergonomics and Optimization

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Overview

Specific requirements

What are dot products?

Hint set 1

Hint set 2

Hint set 3

More things to try

Next steps

Comp-L3-Prog.VRp: Intermediate VR Development

Intermediate VR Development

aaron.sharp@unity3d.com bCXcG*RnEp9O!6@q

D.4.3.3_Dot-product-visualization_edited.mp4

D.4.3.7_Minimum-swipe-speed_edited.mp4

You’re ready to move on to the second, more challenging feature from the project brief: the keycard reader. This feature will require you to detect precise positions and angles as the card enters and exits the reader, so it will require some 3D vector skills. 

In this tutorial, you will do the following: 

Program a custom VR keycard reader according to the requirements of the project brief, with the help of optional hints

Use mathematical formulas, such as dot products, to program custom 3D interactions

Games

Film

Automotive

Skill-L3-Prog.VRp-3: Program custom VR interactions in order to meet the requirements of a project brief.

o-L3-Prog.VRp-3.1: Demonstrate familiarity with the XR Interaction Toolkit (XRIT) API by identifying a high-level approach for programming a given feature in VR.

o-L3-Prog.VRp-3.2: Extend the functionality of the default interactable and interactor objects by overriding the provided events in the XRIT.

o-L3-Prog.VRp-3.3: Perform mathematical calculations on 3D vectors in order to program custom 3D interactions in VR.

Program custom VR interactions in order to meet the requirements of a project brief.

The Keycard Reader

Project 2: Escape Room Project brief 

The second feature you’ll implement from the project brief is the keycard reader. The user must be able to swipe their keycard through a card reader to unlock the door. 

The specific requirements for the key card are listed in the next step. 

As a reminder, if you aren’t sure how to implement one of these requirements, three sets of hints are available to you. We recommend that you attempt to get it working before moving on to the next set of hints. 

If you go through all three sets of hints and are still stuck, at the very end of this project you will be able to download and inspect the completed scripts. Even if you can’t get it working, you will still learn a lot by attempting it and then reviewing someone else’s functional code. 

The Keycard GameObject is selected, and is positioned vertically in the Keycard Reader.

The must-have requirements for the keycard reader are outlined in the full project brief and listed here for your convenience: 

The CardReader.cs script must extend the XRSocketInteractor class, but the keycard should not snap into the socket like a typical socket.

The swipe should only register if the card is swiped down a minimum distance through the reader.

When a swipe is successful, the lock and bar across the door should disappear.

Using a dot product in your code might be helpful to get the keycard reader functioning correctly. 

A dot product is a concept in geometry that tells you how much two vectors point in the same direction. It’s called a dot product because you use a centered dot ( · ) when writing the operation. For example, the dot product of A and B could be written as “A · B”; this would be pronounced “A dot B”.

In this project, using a dot product can help you determine if the keycard is pointing in the same direction as the keycard reader. 

If two vectors point in the same direction, the dot product is positive. 


If two vectors point in opposite directions, the dot product becomes negative. 

If two vectors are perpendicular, the dot product is 0.  

If the vectors are somewhere between parallel and perpendicular, the dot product is something in between. 

To help you visualize this, check out the demonstration video below:  

In the above video, the green line represents the pull direction vector, the sliding door itself represents the actual door direction, and the red line represents the dot product of the pull direction and the door direction (or in other words, pull direction · door direction).  

As you probably guessed, this concept will also be helpful when you’re programming the sliding door in the final tutorial.

You can read more about Unity’s implementation of dot products in the documentation. 

Programmers of 3D applications – including in VR – commonly use algebraic or geometric operations like this. Being comfortable working with angles, velocities, and rotations is critical for custom VR development, so it’s good to get some practice using them now!

Two arrows facing the same direction followed by the equation A . B = +1 This illustrates that when A and B are in the same direction the dot product is positive 1.

Two arrows facing opposite directions followed by the equation A . B = -1 This illustrates that when A and B are in opposite directions the dot product is negative 1.

Two arrows at a right angle from each other followed by the equation A . B = 0 This illustrates that when A and B are perpendicular the dot product is zero.

Two arrows at an acute angle from each other followed by the equation A . B = 0.33 This illustrates that when A and B are at an angle the dot product will be relative to the size of the angle.

Below is the first set of hints, which includes direction on high-level code architecture and programming logic. Use these hints only after you’ve at least attempted the feature with the guidance above: 

You need to prevent the keycard from snapping into the socket as it would by default – read XRSocketInteractor documentation to figure out how.

When the card enters the socket, save the position of the keycard.

When the card exits the socket, save the exit position of the keycard and determine the path traveled.

Every frame, make sure the angle of the card is appropriate.

Remove the lock if the Vector’s Y component has traveled a large enough distance downward.

Below is the second set of hints, which will point you to specific methods, classes, and documentation that may be helpful for this feature. Use these hints only after you’ve at least attempted the feature with the guidance above:

Extending XRSocketInteractor allows you to detect hover events.

Override CanSelect and return false to prevent objects from snapping to the socket.

In OnHoverEntered, you can get the interactable object from the “args” parameter passed in the method using args.interactableObject.

In OnHoverEntered, save the entry position of the keycard as a Vector3.

In OnHoverExited, subtract the entry position Vector3 from the keycard’s exit position to get the Vector3 traveled by the card. 

If the absolute value of the y component of the Vector traveled by the card is greater than a minimum distance, unlock the door.

Get the dot product between the keycard’s upward direction and the world up Vector to make sure it’s parallel - if the dot product is less than a certain value, cancel the swipe.

Below is the third set of hints, which includes actual snippets of code that you could use for specific features. Use these hints only after you’ve at least attempted the functionality with the guidance above: 

protected override void OnHoverEntered(HoverEnterEventArgs args)
{
  base.OnHoverEntered(args);

  m_KeycardTransform = args.interactableObject.transform;
  m_HoverEntry = m_KeycardTransform.position;
  m_SwipIsValid = true;
}

protected override void OnHoverExited(HoverExitEventArgs args)
{
  base.OnHoverExited(args);
 
  Vector3 entryToExit = m_KeycardTransform.position - m_HoverEntry;

  if (m_SwipIsValid && entryToExit.y < -0.15f)
  {
    VisualLockToHide.gameObject.SetActive(false);
    HandleToEnable.enabled = true;
  }

  m_KeycardTransform = null;
}

private void Update()
{
  if (m_KeycardTransform != null)
  {
    Vector3 keycardUp = m_KeycardTransform.forward;
    float dot = Vector3.Dot(keycardUp, Vector3.up);

    if (dot < 1 - AllowedUprightErrorRange)
    {
      m_SwipIsValid = false;
    }
  }
}

If you want to further develop your skills, explore new concepts, or improve your project, check out some optional activities below. Each one is tagged as either [Easy], [Medium], or [Difficult] so you can choose the level of challenge. 

These activities are entirely optional, so if you’re not interested, no problem – just skip this step. 

We do recommend attempting at least one of them in order to get the most out of this learning experience. Good luck!

[Easy] Feedback for valid and invalid swipes 

There is a red and a green light on the card reader that doesn’t do anything. When the swipe is valid, the green light should come on. When the swipe is invalid, the red light should come on. It would be even more satisfying for the user if sound effects accompanied these.

Right now, the user could take 10 seconds to very slowly move the card through the reader. That’s not how most card readers work. The swipe should only be valid if it moves through the reader at an appropriate speed.

[Difficult] Force the card through a particular path 

A real card reader only allows the card to pass through a very particular path with the defined track. In the current project, though, the card follows your hand’s location, rather than the track itself. Instead, when you move the card close enough, it could snap into the card reader’s track. Then, as you move your hand downward, as long as your hand is close enough to the reader, it could stay perfectly inside that track rather than following any subtle movements of your hand. This would almost be like there was a magnet holding the card in the appropriate spot as long as your hand movement was approximately accurate.

Note: Although this feature is labeled as Difficult, it would be more accurately described as Very Difficult!  

In the next tutorial, you will add the functionality for the door, allowing the user to slide it open and leave the room. 

If you completed the functionality in this tutorial, consider completing the optional features below to develop your skills and the project further.

If you could not successfully meet the requirements or if you’re just curious to see another way to implement the code, you will be able to download the completed scripts and compare your work at the end of this project. 

Keycard reader

Overview Video

1. Overview

2. Specific requirements

3. What are dot products?

4. Hint set 1

5. Hint set 2

6. Hint set 3

7. More things to try

8. Next steps

Complete this tutorial