Too many instances

Question

I am trying to replace a prefab with another. I am using Instantiate and Destroy. I am using Raycast to target the prefab with the mouse.

It works but it instantiates many prefabs instead of just one. And the number of instances that it instantiates varies from 6 instances to 1.

Can someone please help me to find the problem?

C# code:

 using UnityEngine;
 using System.Collections;
 
 public class Srp_LandPositioner : MonoBehaviour {
 
     // Found Mouse select code here:
     // http://answers.unity3d.com/questions/23711/destroy-object-on-mouse-click.html
     
     // Update is called once per frame
     void Update() 
     {
            //this if check for the mouse left click
            if(Input.GetMouseButtonUp(0))
            {
     
               Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
                RaycastHit hit;
             
               //this if checks, a detection of hit in an GameObject with the mouse on screen
               if(Physics.Raycast(ray, out hit))
             {
                  Debug.DrawRay (ray.origin, hit.point);
                 print (hit.collider.gameObject.name);
                 
                 GameObject newApple = Instantiate(GameObject.Find("Pre_Apple"), hit.collider.gameObject.transform.position, hit.collider.gameObject.transform.rotation) as GameObject;
                 newApple.name = "Apple " + newGameLand.transform.position.x + ", " + newGameLand.transform.position.z;
                    Destroy(GameObject.Find(hit.collider.gameObject.name));
                 
                }
         }
     }
 }

Answer 1

Best Answer

Answer by aldonaletto · Jan 07, 2012 at 01:44 AM

You should modify the script a little, and attach it to a single object - the camera, for instance - thus you would not have multiple instances running around:

using UnityEngine; using System.Collections;

public class Srp_LandPositioner : MonoBehaviour {

GameObject apple; // drag apple prefab here GameObject pear; // drag pear prefab here

void Update(){ if(Input.GetMouseButtonUp(0)){ Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition); RaycastHit hit; if(Physics.Raycast(ray, out hit)){ if (hit.transform.CompareTag("Pear")){ GameObject newApple = Instantiate(apple, hit.transform.position, hit.transform.rotation); newApple.name = "Apple " + newGameLand.transform.position.x + ", " + newGameLand.transform.position.z; Destroy(hit.gameObject); } } } } } Notice that the script above is instantiating a prefab, not a scene object: to make the Pre_Apple a prefab, just drag it to the Project view.

Add comment · Show 2 · Share

Xara · Jan 07, 2012 at 02:37 AM 0

Share

@aldonaletto

It worked. Thank you very much.

I had to change your code a bit to look like my previous code to get it to work but the idea to put it in the camera and adding "public GameObject apple;" worked.

I re-added "Debug.DrawRay (ray.origin, hit.point);"

and also re-added "Destroy(GameObject.Find(hit.collider.gameObject.name));" I have seen many examples with just "Destroy(hit.gameObject);" but I can't get it to work;

Also needed to add "(GameObject)" before Instantiate command.

Again thank you. I could not get my head around it.

aldonaletto · Jan 07, 2012 at 05:34 AM 0

Share

Weird thing: Destroy(hit.gameObject) should work... but if it's working your way, ok!

Too many instances

1 Reply

Your answer

Welcome to Unity Answers

Follow this Question

Related Questions