Drag different object simultaneously with multiple finger

Question

I follow this tutorial https://www.youtube.com/watch?v=SrCUO46jcxk

for multitouch, it work. And trying to add drag functionality on each object simultaneously with multiple finger. This is my code for button i add some code to make it draggable each object simultaneously but it work on only single object. I tried all relevant post and tutorial but not able perform, please help??

using System.Collections;
using UnityEngine;

public class Button : MonoBehaviour{

 public Color defaultColour;
 public Color selectedColour;
 private Material mat;

 private Vector3 screenPoint;
 private Vector3 offset;


 void Start(){
  mat = GetComponent<Renderer> ().material;
 }

 void OnTouchDown(){
  mat.color = selectedColour;
  Debug.Log ("Touch Down");

  screenPoint = Camera.main.WorldToScreenPoint (transform.position);
  offset = transform.position - Camera.main.ScreenToWorldPoint (new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z));


  }

 void OnTouchUp(){
  mat.color = defaultColour;
  Debug.Log ("Touch Up");
 }

 void OnTouchStay(){
  mat.color = selectedColour;
  Debug.Log ("Touch Stay");

  Vector3 curScreenPoint = new Vector3 (Input.mousePosition.x, Input.mousePosition.y, screenPoint.z);
  Vector3 curPosition = Camera.main.ScreenToWorldPoint (curScreenPoint) + offset;
  transform.position = curPosition;


 }

 void OnTouchExit(){
  mat.color = defaultColour;
  Debug.Log ("Touch Exit");
 }
}

This code is for Input Touch functionality

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class TouchInput : MonoBehaviour {

     public LayerMask touchInputMask;
    private static List<GameObject> touchList = new List<GameObject>();
    private GameObject[] touchesOld;
    private RaycastHit hit;



    void Update () {

        #if UNITY_EDITOR
        if(Input.GetMouseButton(0) || Input.GetMouseButtonDown(0) || Input.GetMouseButtonUp(0)){
            touchesOld = new GameObject[touchList.Count];
            touchList.CopyTo(touchesOld);
            touchList.Clear();

            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            if(Physics.Raycast(ray, out hit, touchInputMask)){
                GameObject recipient = hit.transform.gameObject;
                touchList.Add(recipient);

                if (Input.GetMouseButtonDown(0)){
                    recipient.SendMessage("OnTouchDown",hit.point,SendMessageOptions.DontRequireReceiver);

                }
                if (Input.GetMouseButtonUp(0)){
                    recipient.SendMessage("OnTouchUp",hit.point,SendMessageOptions.DontRequireReceiver);

                }
                if (Input.GetMouseButton(0)){
                    recipient.SendMessage("OnTouchStay",hit.point,SendMessageOptions.DontRequireReceiver);



                }

            }

            foreach (GameObject g in touchesOld){
                if (!touchList.Contains(g)){
                    g.SendMessage("OnTouchExit",hit.point,SendMessageOptions.DontRequireReceiver);
                }
            }
        }

        #endif


        if (Input.touchCount > 0){
            touchesOld = new GameObject[touchList.Count];
            touchList.CopyTo(touchesOld);
            touchList.Clear();

            foreach (Touch touch in Input.touches){

                Ray ray = Camera.main.ScreenPointToRay (touch.position);
                //RaycastHit hit;

                if (Physics.Raycast(ray, out hit, touchInputMask)){
                    GameObject recipient = hit.transform.gameObject;
                    touchList.Add(recipient);

                    if (touch.phase == TouchPhase.Began){
                        recipient.SendMessage("OnTouchDown",hit.point,SendMessageOptions.DontRequireReceiver);

                    }
                    if (touch.phase == TouchPhase.Ended){
                        recipient.SendMessage("OnTouchUp",hit.point,SendMessageOptions.DontRequireReceiver);
                    }
                    if (touch.phase == TouchPhase.Stationary || touch.phase == TouchPhase.Moved){
                        recipient.SendMessage("OnTouchStay",hit.point,SendMessageOptions.DontRequireReceiver);


                    }
                    if (touch.phase == TouchPhase.Canceled){
                        recipient.SendMessage("OnTouchExit",hit.point,SendMessageOptions.DontRequireReceiver);
                    }
                }
            }
            foreach (GameObject g in touchesOld){
                if (!touchList.Contains(g)){
                    g.SendMessage("OnTouchExit",hit.point,SendMessageOptions.DontRequireReceiver);
                }
            }
        }
    }

}

Answer 1

Now finally perform this process, i could perform this process in two ways

1. Using touchScript library, it has a rich feature we can drag, rotate, translate and scale multiple object in one time. https://www.youtube.com/watch?v=HHLBJ1Ss2S0

   Note: this is older video, now it changes but it is almost same. [TouchScript is available in asset store for free]

2. other option, attach below code in empty gameobject or in camera(add tag layer)

   using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.UI;

   public struct objectst { public Vector3 screenPoint; public Vector3 offset; }

   public class TouchInput : MonoBehaviour {

   public LayerMask touchInputMask;
   private static List<GameObject> touchList = new List<GameObject>();
   public static Dictionary<int,objectst> touchobjects = new Dictionary<int,objectst>();
   
   private GameObject[] touchesOld;
   private RaycastHit hit;
   public Text Count, IndexLift;
   
   private Vector3 targetPos;
   
   
   
   
   
   void Update () {
   
   
       int nbTouches = Input.touchCount;
   
       if(nbTouches > 0)
       {
           nbTouches = 5;
   
           print(nbTouches + " touch(es) detected");
   
           touchesOld = new GameObject[touchList.Count];
           touchList.CopyTo(touchesOld);
           touchList.Clear();
   
           for (int i = 0; i < nbTouches ; i++)
           {
   
   
               Touch touch = Input.GetTouch(i);
   
   
               print("Touch index " + touch.fingerId + " detected at position " + touch.position);
   
               Ray ray = Camera.main.ScreenPointToRay (touch.position);
   
   
               if (Physics.Raycast(ray, out hit, touchInputMask)){
                   GameObject recipient = hit.transform.gameObject;
                   touchList.Add(recipient);
   
                   //recipient.;
   
                   if (touch.phase == TouchPhase.Began){
   
                       objectst tempobj = new objectst ();
                       tempobj.screenPoint = Camera.main.WorldToScreenPoint (recipient.transform.position);
                       tempobj.offset = recipient.transform.position - Camera.main.ScreenToWorldPoint (new Vector3 (touch.position.x, touch.position.y, tempobj.screenPoint.z));           
   
                       touchobjects.Add(touch.fingerId,tempobj);
   
   
   
   
                   }
   
                   if (touch.phase == TouchPhase.Stationary || touch.phase == TouchPhase.Moved){
   
   
                       Vector3 curScreenPoint = new Vector3 (touch.position.x, touch.position.y,
                           touchobjects[touch.fingerId].screenPoint.z);
                       Vector3 curPosition = Camera.main.ScreenToWorldPoint (curScreenPoint) + touchobjects[touch.fingerId].offset;
                       recipient.transform.position = curPosition;
   
   
   
                   }
                   if (touch.phase == TouchPhase.Ended){
   
                       Vector3 curScreenPoint = new Vector3 (touch.position.x, touch.position.y,
                           touchobjects[touch.fingerId].screenPoint.z);
                       Vector3 curPosition = Camera.main.ScreenToWorldPoint (curScreenPoint) - touchobjects[touch.fingerId].offset;
                       recipient.transform.position = curPosition; 
   
                   }
                   if (touch.phase == TouchPhase.Canceled){
   
                   }
               }
   
   
           }
           foreach (GameObject g in touchesOld){
             if (!touchList.Contains(g)){
                   g.SendMessage("OnTouchExit",hit.point,SendMessageOptions.DontRequireReceiver);
           }
   
       }
       }
   
   }
   

   }