Virtual joysticks for Unity3D

VirtualJoystick.cs

/*
 * The following code is part of a tutorial.
 * http://catsoft-studios.com/virtual-joysticks-for-unity3d-mobile-games
 *
**/ 

using UnityEngine;
using System.Collections;

public class  VirtualJoystick : MonoBehaviour 
{
	private bool isControllable = true;
	[HideInInspector]
	public Vector2 movement = Vector2.zero;
	
	private Texture2D padBackgroundTexture;
	private Texture2D padControllerTexture;
	private Rect padBackgroundRect = new Rect(0,0, 100, 100);
	private Rect padControllerRect = new Rect(0,0, 100, 100);
	
	private Vector2 padBackgroundPosition = Vector2.zero;
	private Vector2 padControllerPosition = Vector2.zero;
	private const float padRadius = 50.0f;
	
	private bool isMovingFinger = false;
	
	public void Awake()
	{
		this.padBackgroundTexture = new Texture2D(1,1);
		this.padBackgroundTexture.SetPixel(0,0, new Color(0f,0f,0f, 0.5f));
		this.padBackgroundTexture.Apply();
		
		this.padControllerTexture = new Texture2D(1,1);
		this.padControllerTexture.SetPixel(0,0, new Color(1f,1f,1f));
		this.padControllerTexture.Apply();
	}
	
	public void Update()
	{
		if (this.isControllable && Input.touchCount == 1)
		{
			Touch touch = Input.touches[0];
			Vector2 touchPosition = new Vector2(touch.position.x, Screen.height - touch.position.y);
			
			switch (touch.phase)
			{
			case TouchPhase.Began :
				this.isMovingFinger = true;
				this.padBackgroundPosition = touchPosition;
				this.padControllerPosition = touchPosition;
				break;
					
			case TouchPhase.Moved :
				this.padControllerPosition = touchPosition;
				float padsDistance = Vector2.Distance(this.padBackgroundPosition, this.padControllerPosition);
				if (padsDistance > PlayerJoystick.padRadius)
				{
					Vector2 padDirection = this.padControllerPosition - this.padBackgroundPosition;
					float t = PlayerJoystick.padRadius/padsDistance;
					this.padBackgroundPosition = Vector2.Lerp(this.padControllerPosition, this.padBackgroundPosition, t);
				}
				break;
					
			case TouchPhase.Stationary :
				break;
				
			case TouchPhase.Canceled :
			this.isMovingFinger = false;
				this.padBackgroundPosition = this.padControllerPosition;
				break;
				
			case TouchPhase.Ended :
				this.isMovingFinger = false;
				this.padBackgroundPosition = this.padControllerPosition;
				break;
			}
		}
		
		Vector2 direction = (this.padControllerPosition - this.padBackgroundPosition);
		float distance = Vector2.Distance(this.padControllerPosition, this.padBackgroundPosition);
		
		if (PlayerJoystick.padRadius/distance > 3.5f) this.movement = Vector2.zero;
		else
		{
			this.movement = direction.normalized;
			
			// if the joystick is not being fully pushed, divide the movement by two
			// (to make the player walk or run):
			if (PlayerJoystick.padRadius/distance > 1.5f) this.movement /= 2.0f;
		}
	}
    
	public void SetIsControllable(bool isControllable)
	{
		this.isControllable = isControllable;
	}
	
	public bool GetIsControllable()
	{
		return this.isControllable;
	}
	
	public void OnGUI()
	{
		if (this.isMovingFinger && this.isControllable)
		{
			Rect backgroundRect = new Rect(
				this.padBackgroundPosition.x - (this.padBackgroundRect.width/2.0f),
				this.padBackgroundPosition.y - (this.padBackgroundRect.height/2.0f),
				this.padBackgroundRect.width,
				this.padBackgroundRect.height
			);
			
			Rect controllerRect = new Rect(
				this.padControllerPosition.x - (this.padControllerRect.width/2.0f),
				this.padControllerPosition.y - (this.padControllerRect.height/2.0f),
				this.padControllerRect.width,
				this.padControllerRect.height
			);
			
			GUI.DrawTexture(backgroundRect, this.padBackgroundTexture);
			GUI.DrawTexture(controllerRect, this.padControllerTexture);
		}
	}
}