and applications with Unity is easy.

In this video I'll go over the concepts and implementation

of adding Cardboard support to a Unity project.

As you may know, Unity is a game engine

with an editor that allows you to easily import 3-D models

and arrange them in the scene.

You can also attach scripts to objects

to give them functionality.

Before we start, make sure to get the Cardboard Unity

plugin from this link.

Then, open your Unity project and import a package like this.

Now that they are all set, there are two things you need to do.

You need to create a stereoscopic camera

and make sure your user interface works well

for virtual reality.

Let's start with adding the camera and look into modifying

the UI at the end.

You can do so by using one of the available prefabbed objects

or by attaching a script to an existing camera.

The easiest way is to use the Cardboard main prefab.

This is best if you're starting a new project

or haven't made any changes to your existing camera.

Simply replace the existing camera with the Cardboard

main prefab, and you're done.

You can still add any custom scripts on top,

for controlling the camera, for example.

Press Play, and you'll have a functioning scopic view.

You can rotate the camera using the Alt key

while moving the mouse.

To simulate Cardboard Trego, press the left mouse button.

If you already have a camera, you

can use the Cardboard adapter prefab.

Add it as a child of your camera and select

Update Stereo Cameras from the Components menu.

Once again, you can press Play and have

a functioning stereoscopic view in the game window.

If you don't want to use a prefab,

then you can just use a script.

By adding the stereo controller script to your camera,

two stereoscopic cameras will be created dynamically

as you press play.

You may not want to use the stereo controller script

since it doesn't let you add any image processing on top

of the cameras because they are added dynamically.

If you want to create the cameras in the Editor,

then simply select Update Stereo Cameras from the menu

and they will be created for you.

Press Play, and you are done.

Last thing we have to do is get the user interface working

and add support for the Trego.

Start by adding the [INAUDIBLE] Input Module script

to the [INAUDIBLE] Event System Object.

This script emits [INAUDIBLE] for the event system

based on the user's gaze.

Next, in your UI element, set the Conference Render mode

to [INAUDIBLE] Space and set the event camera

to a camera controlled by a Cardboard head script,

either directly or as a parent.

At this point, the system is able to respond to the user's

gaze into triggers so that UI elements, such as buttons,

can be activated.

If you wish to interact with 3-D objects in the scene,

add a physics ray caster component to the event camera.

Designate an in-game object to be interactive

by adding a collider component to interact with the ray

caster.

And by adding a script to respond

to the generated events.

An event trigger is a good choice,

or you can implement some of the standard Unity event interfaces

on your own scripts.

If you wish to add a cursor to let a user see

the point of their gaze, set the Gaze Input models cursor

to the game object that will serve [INAUDIBLE].

This cursor will be moved to the exact point on whatever UI

object the user is gazing at.

If the event camera has a physics ray caster,

then this includes 3-D objects with the collider components.

If no object is hit by a ray cast, the cursor is hidden.

Now that you know how to make everything work,

it is important to keep in mind some best practices in order

to make a compelling virtual reality experience.

The three most important words to remember

are always keep tracking on, keep stable 60 frames

per second or higher, and avoid unexpected motion.

One of the things that makes virtual reality compelling

is the ability to look around.

In contrast, it would feel extremely unnatural

if the camera stopped responding to your head.

Therefore, you should always take into account

the user's orientation and never freeze the camera

or force the user to look somewhere specific.

If you want to grab the user's attention,

use cues such as light and sound to direct

them to look where you want.

You can also delay activating an event in your scene

until you know the user had turned

their head in that direction.

That way, they have time to take things in and enjoy the scene.

You must always keep to 60 FPS or higher.

Not only does it contribute to a good user experience,

but it is even more crucial in virtual reality.

Think about it this way, the screen

is the only thing the user can see.

Rendering at 60 FPS means the user sees the same flame

for 16.6 milliseconds.

If you miss 60 FPS, vsync drops you to 30 FPS and its frame

is shown for 33 milliseconds.

That means as the user moves their head,

they're getting an incorrect image for a very long time.

This is why it is very important for virtual reality

applications to be fast and responsive.

Movement can be tricky, because the user does not

feel like they are in motion.

If the world starts moving around,

it can contribute to an odd feeling

if there is discrepancy between one's actual lack of movement

and what the user is seeing.

There are ways to convey movement safely.

For example, by keeping motion constant

and avoiding acceleration, or by using another object and making

it move first or creating a path for the user to see.

This signals to the user they're about to be moved

and subconsciously propels them.

There are many more ways to ensure a good user experience.

I recommend you to check out the Cardboard Design Lab

Application to learn more about good and bad design patterns

so you can create the best user experience in your game

or application.

Good luck with making your own virtual reality experience,

and make sure to post about it in our Cardboard community.