Changing card position - unity3d

Question

I am creating a card game in unity. I have 4 cards and instantiated them randomly 16 times on 4 zones when a button is clicked. Each zone contains 4 random cards. I want to know how can I know which card is in which zone and then change the position of that particular card to another zone.
This is the script attached to each of my card:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Click : MonoBehaviour
{
public GameObject Canvas;
public GameObject MyArea;
private bool isDragging=false;
private bool isOverBottomArea=false;
private GameObject BottomArea;
private GameObject startParent;
private Vector2 startPosition;
private void Awake()
{
MyArea=GameObject.Find("MyArea");
Canvas=GameObject.Find("Canvas");
}
// Update is called once per frame
void Update()
{
if (isDragging)
{
transform.position= new Vector2(Input.mousePosition.x,Input.mousePosition.y);
transform.SetParent(Canvas.transform, true);
}
}
private void OnCollisionEnter2D(Collision2D collision)
{
isOverBottomArea=true;
BottomArea=collision.gameObject;
}
private void OnCollisionExit2D(Collision2D collision)
{
isOverBottomArea=false;
BottomArea=null;
}
public void StartDrag()
{
startParent= transform.parent.gameObject;
startPosition=transform.position;
if(startParent != MyArea)
{
isDragging=false;
}
else
{
isDragging=true;
}
}
public void EndDrag()
{
isDragging=false;
if (isOverBottomArea && startParent==MyArea )
{
transform.SetParent(BottomArea.transform, false);
}
else
{
transform.position=startPosition;
transform.SetParent(startParent.transform, false);
}
}
}
And this is the script attached to the button which on clicking instantiate the 16 cards:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DrawCards : MonoBehaviour
{
public GameObject Card1;
public GameObject Card2;
public GameObject Card3;
public GameObject Card4;
public GameObject MyArea;
public GameObject LeftArea;
public GameObject RightArea;
public GameObject BottomArea;
List<GameObject> cards = new List<GameObject>();
void Start()
{
cards.Add(Card1);
cards.Add(Card2);
cards.Add(Card3);
cards.Add(Card4);
}
int count1 = 0;
public void OnClick()
{
count1++;
if (count1 == 1)
{
for (var i=0; i<4; i++)
{
GameObject playerCard = Instantiate(cards[Random.Range(0, cards.Count)], new Vector3(0,0,0), Quaternion.identity);
playerCard.transform.SetParent(MyArea.transform, false);
GameObject leftCard = Instantiate(cards[Random.Range(0, cards.Count)], new Vector3(0,0,0), Quaternion.identity);
leftCard.transform.SetParent(LeftArea.transform, false);
GameObject rightCard = Instantiate(cards[Random.Range(0, cards.Count)], new Vector3(0,0,0), Quaternion.identity);
rightCard.transform.SetParent(RightArea.transform, false);
GameObject bottomCard = Instantiate(cards[Random.Range(0, cards.Count)], new Vector3(0,0,0), Quaternion.identity);
bottomCard.transform.SetParent(BottomArea.transform, false);
}
}
}
}

Answer 1

I would consider storing the values to each of your 4 zones with card data to be utilized later. I do not exactly know what a zone is or what it means if there can be more than 4 cards to a zone, etc.
Here is a very general approach to having zones, cards and a zone manager. I can help clarify any details as to what the code does but I commented it quite extensively. I did not integrate it into your code but rather it should be used as a template by you to do so. The code I am providing is untested and should not just be copy-pasted as your question is still rather general. I can explain anything further if you need.
Card class on each moveable card
// this class is on each of your cards
public class Card : MonoBehaviour,
{
// current index of this card
private int cardIndex = -1;
// stores the current zone this card is in
private Zone currentZone = null;
// init this object with the zone it is in and the card index it has
public void InitCard(Zone zone, int idx)
{
cardIndex = idx;
currentZone = zone;
}
// I am using the same EndDrag - I am assuming you are using an editor component of EventTrigger with an
// OnBeginDrag and OnEndDrag instead of implementing the IHandlers in code
public void EndDrag()
{
// determine if we are over a zone - I am going to use the MouseInput as with a drag,
// you would be dragging the object using the cursor or a finger
RaycastHit hit;
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
// only look for the layer of the Zone objects
// make sure to add a layer to just the zones and make sure
// it is spelled / case-sensative so exactly the same
int layer_mask = LayerMask.GetMask("ZoneLayer");
// if we hit a zone, determine if it is a new zone and to move the card
if(Physics.Raycast (ray, out hit, Mathf.Infinity, layer_mask))
{
Zone newZone = hit.gameObject.GetComponent<Zone>();
// we hit a zone, is it the same zone?
if(currentZone == newZone)
{
// handle however you want to do a case where it is the same zone
// reset the card position possibly
return;
}
// we are in a new zone, so need to remove this card from the old zone and add it to the new one
// I am not sure how you are handling max card counts in each zone, etc. so this is very basic implementation
currentZone.RemoveCard(this);
newZone.AddCard(this);
// update our local zone reference
currentZone = newZone;
}
}
// setters / getters
public int CardIndex
{
set{cardIndex = value;}
get{return cardIndex;}
}
public Zone CurrentZone
{
set{currentZone = value;}
get{return currentZone;}
}
}
ZoneManager should be on an object that manages your individual zones, so possibly the Canvas object that all of this data is on
// this class will manage each one of your zones
public class ZoneManager : MonoBehaviour
{
// list of our prefabs
[SerializeField] private List<GameObjects> allCardsPrefabList = new List<GameObjects>();
// create a list of zone data of size 4
[SerializeField] private Zone[] myZoneData = new Zone[MAX_ZONE_COUNT];
// max number of zones we can have
private const int MAX_ZONE_COUNT = 4;
// max number of cards we can have on Init
private const int MAX_INIT_CARD_COUNT = 4;
// init our zones in Start() - as I do not know if you are working with UI
// and UI components are only set before Start but not Awake
private void Start()
{
// iterate over each zone
for(int x = 0; x < MAX_ZONE_COUNT; ++x)
{
// iterate over 4 new cards
for(int y = 0; y < MAX_INIT_CARD_COUNT; ++y)
{
// I am using this overload of the Instantiate
// public static Object Instantiate(Object original, Transform parent, bool instantiateInWorldSpace);
// grab our new idx
int newCardIdx = Random.Range(0, cards.Count);
// spawn a new card childed to our zone at the new card idx
Card newCard = Instantiate(allCardsPrefabList[newCardIdx], myZoneData[x].transform, false).GetComponent<Card>();
// init our card zone / idx
newCard.Init(myZoneData[x], newCardIdx);
// add this card to a zone
myZoneData[x].AddNewCard(newCard);
}
}
}
}
The Zone class should be on each of your individual zones
// this is a script that will house each of your zones and will be used to add cards to your zone
public class Zone : MonoBehaviour
{
private const int MAX_INIT_CARDS = 4;
// list of our current cards of this zone
public List<CardData> zoneCards = new List<CardData>();
// called from when a cast is detected on a drop
public void AddNewCard(Card newCard)
{
zoneCards.Add(newCard);
}
// remove a card instance from our list as it is no longer apart of this zone
public void RemoveCard(Card oldCard)
{
zoneCards.Remove(oldCard);
}
}
Again, this is a general idea, not a straightforward answer. Use it as a template to add to your existing code.