Mobile & Touch Input

Mobile & Touch Input

Developing games for mobile devices requires handling touch screens, multi-touch gestures, and virtual joystick interfaces.

Detecting Touches in C#

To check for finger touches on mobile screens:

void Update()
{
    // Check if any fingers are touching the screen
    if (Input.touchCount > 0)
    {
        Touch touch = Input.GetTouch(0);

        if (touch.phase == TouchPhase.Began)
        {
            Debug.Log("Touch started at: " + touch.position);
        }
        else if (touch.phase == TouchPhase.Moved)
        {
            Debug.Log("Finger is sliding: " + touch.deltaPosition);
        }
    }
}

Touch Phases

The TouchPhase enum describes the state of a finger:

• Began: The finger touched the screen this frame.
• Moved: The finger moved on the screen.
• Stationary: The finger is touching the screen but not moving.
• Ended: The finger was lifted from the screen.
• Canceled: The system canceled tracking for the touch (e.g. phone call interrupt).

Virtual Joysticks & Buttons

For mobile action games, you can place UI images on screen that act as virtual controls. The Input System package includes a Onscreen Stick and Onscreen Button component:

1. Place a UI Image for a joystick knob.
2. Add the On-Screen Stick component.
3. Assign a control path (e.g. Gamepad/leftStick).
4. The stick knob converts drag gestures into standard gamepad inputs automatically.

TL;DR

• Use Input.touchCount and Input.GetTouch to read mobile screen inputs.
• TouchPhase enums track finger actions (Began, Moved, Ended).
• Use On-Screen Stick components to implement mobile virtual joysticks easily.