Touch input basics in Unity - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a Touch in Unity?

A Touch represents a single finger touching the screen. It contains information like position, phase (start, move, end), and finger ID.

beginner

How do you check if the screen is being touched in Unity?

Use Input.touchCount. If it is greater than zero, the screen has one or more touches.

beginner

What does TouchPhase.Began mean?

It means a finger just touched the screen this frame. It's the start of a touch.

beginner

How can you get the position of a touch on the screen?

Use touch.position, which gives the x and y coordinates in pixels from the bottom-left corner.

intermediate

Why is fingerId important in touch input?

fingerId helps track individual fingers across frames, so you know which touch is which when multiple fingers are on the screen.

Which property tells you how many fingers are currently touching the screen?

A Input.touchCount

B Input.touchPosition

C Touch.fingerId

D Touch.phase

Input.touchCount returns the number of active touches on the screen.

What does TouchPhase.Moved indicate?

A A finger just touched the screen

B A finger moved on the screen

C A finger was lifted off the screen

D No finger is touching the screen

TouchPhase.Moved means the finger has moved since the last frame.

How do you access the position of the first touch on the screen?

A Input.touchCount.position

B Input.touchPosition[0]

C Touch.position[0]

D Input.GetTouch(0).position

Input.GetTouch(0) gets the first touch, and .position gives its screen coordinates.

What is the purpose of fingerId in a Touch object?

A To identify the finger across frames

B To get the finger's pressure

C To get the finger's speed

D To get the finger's color

fingerId uniquely identifies each finger touching the screen so you can track it over time.

Which TouchPhase means the finger was lifted off the screen this frame?

A TouchPhase.Began

B TouchPhase.Stationary

C TouchPhase.Ended

D TouchPhase.Canceled

TouchPhase.Ended means the finger stopped touching the screen this frame.

Explain how you would detect a single tap on the screen using Unity's touch input.

Think about checking if a finger just touched the screen and where.

Describe the role of the TouchPhase property and list its main states.

TouchPhase tells you what is happening with a finger each frame.