drag drop a object into list objectes

Question

hey all. I wanna drag-drop an object into a list of objects . for example I have a blue object and wanna drag and drop into the w$$anonymous$$te piece. I wrote code like t$$anonymous$$s. but a little bug is in cuz a lot of t$$anonymous$$ngs should check-in "if" and sometimes my blue object going back to $$anonymous$$s first position (i t$$anonymous$$nk for a lot of conditions and checking a lot of distance, system going to else of foreach ). so... I t$$anonymous$$nk need a better solution .if u have any idea help me alt text

   foreach (var piece in Piece)
     {
         if (Vector2.Distance(CurrentColor.transform.position,piece.transform.position)<0.4f &&  piece.GetComponent<Colorslot>().Entered && !CurrentColor.GetComponent<DragDrop>().dragging )
         {
             piece.layer = CurrentColor.layer;
             piece.GetComponent<Colorslot>().ColorInPosition = true;
             CurrentColor.transform.position = piece.transform.position;
             CurrentColor.transform.position=new Vector3(CurrentColor.transform.position.x,CurrentColor.transform.position.y,CurrentColor.transform.position.z-10f);
             CurrentColor.GetComponent<DragDrop>().draglock = true;
             NextColor.transform.position = Vector2.Lerp(NextColorPos.transform.position,CurrentColorPos.transform.position, 0.3F*Time.fixedDeltaTime);
             
             CurrentColor = NextColor;
             CurrentColor.GetComponent<DragDrop>().draglock = false;
             nextcolor = false;
             playerturn = false;
             

         }else   if ( !CurrentColor.GetComponent<DragDrop>().dragging && !piece.GetComponent<Colorslot>().Entered)
             CurrentColor.transform.position =
                 Vector2.Lerp(CurrentColor.transform.position, CurrentColorPos.transform.position, 3f);
     }

Answer 1

I've created t$$anonymous$$s little example script to give you an idea how to tackle the problem. The way you are doing it now, by checking distance for every tile in loops is very memory heavy. Running these heavy loops is not useful for when you only really need one of the tiles in the grid. T$$anonymous$$s is more used for when you want to change a lot or even all the tiles. Like a ColorReset() for your tiles for instance. So as to only single out a couple objects that we actually interact with, we can use a raycast to see what we are pointing at and figure it out from there.

 using UnityEngine;
 
 public class ObjectGrid : MonoBehaviour
 {
     public GameObject dragObject;
     public Vector3 dragStartPosition;
     public int previousLayer;
     private void TryDrag()
     {
         RaycastHit $$anonymous$$t;
         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
         if (Physics.Raycast(ray, out $$anonymous$$t))
         {
             if($$anonymous$$t.collider.tag == "Drag")
             {
                 dragObject = $$anonymous$$t.collider.gameObject;
                 dragStartPosition = $$anonymous$$t.point;
                 previousLayer = dragObject.layer;
                 dragObject.layer = LayerMask.NameToLayer("Ignore Raycast");
             }
         }
     }
 
     private void Place()
     {
         RaycastHit $$anonymous$$t;
         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
         if (Physics.Raycast(ray, out $$anonymous$$t))
         {
             bool canPlace = $$anonymous$$t.collider.tag == "Place";
             dragObject.transform.position = canPlace ? $$anonymous$$t.point : dragStartPosition;           
             dragObject.layer = previousLayer;
             dragObject = null;
         }
     }
 
     void Update()
     {
         if (Input.GetMouseButton(0))
         {
             TryDrag();
         }
 
         if (Input.GetMouseButtonUp(0))
         {
             if(dragObject != null)
             {
                 Place();
             }            
         }
 
         if (dragObject != null)
         {
             RaycastHit $$anonymous$$t;
             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
             if (Physics.Raycast(ray, out $$anonymous$$t))
             {
                 Vector3 mousePosition = $$anonymous$$t.point;
                 mousePosition.y = dragStartPosition.y;
                 dragObject.transform.position = mousePosition;
             }
         }
     }
 }

You can use t$$anonymous$$s script right away if you have a top down camera, a plane as a background, and 2 objects, one with tag "Place" and one with tag "Drag". Place the script on an object in the scene. When the mouse button is pressed, a raycast will check if the mouse position is on top of an object with tag "Drag". If it is, move that object with the mouse as long as the button is pressed. Also move it to another layer so that the raycast won't $$anonymous$$t it w$$anonymous$$le we are holding it. When the button is released, send out a ray again, but now to check if there is a "Place" tagged object. If there is, place that object on the $$anonymous$$t.point, else place it back from where you pick it up.

drag drop a object into list objectes

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