TouchEvent to MouseEvent for Unity

TouchToMouseConverter.cs

/**
Converts Mobile Touch to the default Mouse Click

## invoked these method in Mobile too
OnMouseDown
OnMouseDrag
OnMouseUp 


## only called in touch screen
OnPinchStart
OnPinch(rate:float);
OnPinchEnd


@author koki ibukuro
*/
#region Namespaces
using System;
using System.Collections;
using System.Reflection;
using UnityEngine;
#endregion


[AddComponentMenu ("Common/Components/Touch To Mouse Converter")]
public class TouchToMouseConverter : MonoBehaviour {
/**
 State for convert mouse event
*/
private enum TouchToMouseState {
	Down,
	Drag,
	Up,
	Pinching,
	PinchEnd
}

public bool isOn = true;

private TouchToMouseState touchState = TouchToMouseState.Up;
private RaycastHit hit;
private Transform beforeTransform;

//private float DRAGGING_DISTANSE = 100f;

static private ToughToMouseConverter instance;
static Camera cam;
static Transform camTransform;

static private int kRaycastLayers = 1 << 0;   // 1 << 8  Physics

/// <summary>
/// 	returns mouse or first touched point
/// </summary>
/// <returns></returns>
static public Vector3 GetMousePosition() {
	if(Input.touchCount > 0) {
		return Input.GetTouch(0).position;
	}	
	return Input.mousePosition;
}


/// <summary>
/// 	returns mouse or touched point in World
/// </summary>
static public Vector3 GetWorldMousePosition() {
	Vector3 mousePosition = GetMousePosition();
	Vector3 cameraPosition = camTransform.position;
	return cam.ScreenToWorldPoint(new Vector3(mousePosition.x, mousePosition.y, cameraPosition.z));
}

static public ToughToMouseConverter GetInstance() {
	return instance;
}


/// <summary>
/// 	set Using camera
/// </summary>
static public void SetCamera(Camera c) {
    cam = c;
	camTransform = c.transform;
}

void Awake () {
	if(instance) {
		Debug.LogError("ToughToMouseConverter class is Singleton. use GetInstance()");
		return;	
	}
	instance = this;	
}

void Start () {
	if(!cam) {
		SetCamera(Camera.main);
	}
}

void Update () {
	if (!isOn) {
		return;
	}
	int count = Input.touchCount;
	if ( count == 1 ) {
		if(touchState == TouchToMouseState.Pinching ) {
			touchState = TouchToMouseState.PinchEnd;
			toPinchEnd();
		}
		else if(touchState == TouchToMouseState.PinchEnd) {
			// nothing to do
		}
		else {
			singleTouch();
		}
	}
	else if( count >= 2 ) {
		multiTouch();
	}
	else {
		noTouch();
	}
	callGC();
}


private void singleTouch() {
	Touch touch = Input.GetTouch(0);
	Ray ray = cam.ScreenPointToRay ( touch.position);
	
	// if it has hitting object....
	//if ( !UIManager.instance.DidAnyPointerHitUI() && Physics.Raycast( ray, hit, Mathf.Infinity, kRaycastLayers) )  {
	if ( Physics.Raycast( ray, out hit, Mathf.Infinity, kRaycastLayers) )  {
		// start touch
		if(touch.phase == TouchPhase.Began) {
			toDown();
		}
		// touch move
		else if(touch.phase == TouchPhase.Moved) {
			if(beforeTransform == hit.transform) {
				toDrag();
			}
			else {
				toOldUp();
				toDown();
			}
		}
		// end touch
		else if(touch.phase == TouchPhase.Ended || touch.phase == TouchPhase.Canceled) {
			toUp();
		}
		
		if(touchState == TouchToMouseState.Drag && hit.transform != beforeTransform){
			toOldUp();
		}
		
	}
	else {
		// if dragging,,, send message to the old touched object
		if(touchState == TouchToMouseState.Drag) {
			if(touch.phase == TouchPhase.Moved) {
				toOldDrag();
			}
			else if(touch.phase == TouchPhase.Ended || touch.phase == TouchPhase.Canceled) {
				toOldUp();
			}
		}
	}
}


private float _touchesDistance = 0;
private void multiTouch() {
	Touch a = Input.GetTouch(0);
	Touch b = Input.GetTouch(1);
	if((a.phase == TouchPhase.Stationary || a.phase == TouchPhase.Moved)
	 &&(b.phase == TouchPhase.Stationary || b.phase == TouchPhase.Moved))
	{   
		Ray ray = cam.ScreenPointToRay ( a.position);

		// There are hitting objects..
		if ( Physics.Raycast( ray,out hit, Mathf.Infinity, kRaycastLayers) )  {
			float d = Vector2.Distance(a.position, b.position);
			if(touchState != TouchToMouseState.Pinching) {
				_touchesDistance = d;
				toPinchStart();
				touchState = TouchToMouseState.Pinching;
			}
			else {
				toPinch(d/_touchesDistance);
			}
		}
		else {
		 
		}
	}
}


private void noTouch() {
	if(touchState == TouchToMouseState.Pinching) {
		touchState = TouchToMouseState.PinchEnd;
	}
	else if(touchState == TouchToMouseState.PinchEnd) {
		touchState = TouchToMouseState.Up;
	}
	else if(beforeTransform) {
		toOldUp();
	}
}

private void callGC() {
	if(Time.frameCount % 30 == 0) {
		System.GC.Collect();
	}
}


private void toDown() {
	hit.transform.SendMessage("OnMouseDown",null, SendMessageOptions.DontRequireReceiver);
	touchState = TouchToMouseState.Down;
	beforeTransform = hit.transform;
}

private void toDrag() {
	hit.transform.SendMessage("OnMouseDrag",null, SendMessageOptions.DontRequireReceiver);
	touchState = TouchToMouseState.Drag;
	beforeTransform = hit.transform;
}

private void toUp() {
	hit.transform.SendMessage("OnMouseUp",null, SendMessageOptions.DontRequireReceiver);
	touchState = TouchToMouseState.Up;
	beforeTransform = null;
}

private void toOldDrag () {
	beforeTransform.SendMessage("OnMouseDrag",null, SendMessageOptions.DontRequireReceiver);
}

private void toOldUp () {
	if(beforeTransform)beforeTransform.SendMessage("OnMouseUp",null, SendMessageOptions.DontRequireReceiver);
	beforeTransform = null;
}

private void toPinchStart() {
	hit.transform.SendMessage("OnPinchStart",null, SendMessageOptions.DontRequireReceiver);
}

private void toPinch(float rate) {
	hit.transform.SendMessage("OnPinch",rate, SendMessageOptions.DontRequireReceiver);
}

private void toPinchEnd() {
	hit.transform.SendMessage("OnPinchEnd",null, SendMessageOptions.DontRequireReceiver);
}

}

• i changed your source for editor Touch.
  https://gist.github.com/whdvl/7117513

Can you give me some tips on how to convert this to work with 2D colliders?