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Unity (C#) - How do I single out GameObject being detected by Raycast in a destroy / respawn system

I'm trying to make a Destroy gameobject, wait x seconds, respawn gameobject system. I have 2 scripts and I'm destorying then instantiating it again. I want to use multiples of the same prefab called "Breakable" but have only the one I'm aiming at being destroyed. Similar to games like Minecraft, aim and only the aimed at the block is destroyed.
BlockBreakItem script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class BlockBreakItem : MonoBehaviour
{
RaycastHit hit;
int layerMask = 1;
public GameObject breakableObject;
public bool isObjectDestoryed = false;
public int score = 0;
// Update is called once per frame
void Update()
{
breakableDetection();
}
void breakableDetection()
{
Ray rayLocation = Camera.main.ScreenPointToRay(Input.mousePosition);
if (Physics.Raycast(rayLocation, out hit, 1000, layerMask))
{
print("Detected");
if (Input.GetKey(KeyCode.Mouse0))
{
breakableObject = GameObject.Find("Breakable");
Destroy(breakableObject);
isObjectDestoryed = true;
score = score +1 ;
}
}
}
}
RespawnBrokenObject script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class RespawnBrokenObject : MonoBehaviour
{
private BlockBreakItem BlockBreakItem;
public GameObject breakablePrefab;
// Start is called before the first frame update
void Start()
{
BlockBreakItem = GameObject.FindObjectOfType<BlockBreakItem>();
}
// Update is called once per frame
void Update()
{
if (BlockBreakItem.isObjectDestoryed == true)
{
Invoke("respawnObject", 5.0f);
BlockBreakItem.isObjectDestoryed = false;
}
}
void respawnObject()
{
GameObject tempObjName = Instantiate(breakablePrefab);
tempObjName.name = breakablePrefab.name;
BlockBreakItem.breakableObject = tempObjName;
}
}
I hope the code isn't too messy! Always worried it won't be understood xD

Fortunately it's easy and basic in Unity!
You don't do this:
breakableObject = GameObject.Find("Breakable");
The good news is the cast will tell you what object you hit! Great, eh?
It's basically:
hit.collider.gameObject
You can use hit.collider.gameObject.name in a Debug.Log for convenience.
It's that easy!
Note you then (if you need it) get your component on that object with something like .GetComponent<YourBreakishBlock>()... easy.
Note that you can CHECK if the object hit, is one of the "YourBreakishBlock" objects, by simply checking if that component is present.
Note simply google something like "unity physics raycast out hit, which object was hit ?" for endless examples,
https://forum.unity.com/threads/getting-object-hit-with-raycast.573982/
https://forum.unity.com/threads/changing-properties-of-object-hit-with-raycast.538819/
etc.
--
Make this simple class:
public class ExamplePutThisOnACube: MonoBehavior
{
public void SAYHELLO() { Debug.Log("hello!"); }
}
Now put that on SOME cubes but NOT on OTHER cubes.
In your ray code:
ExamplePutThisOnACube teste =
hit.collider.gameObject.GetComponent<ExamplePutThisOnACube>();
and then check this out:
if (teste != null) { teste.SAYHELLO(); }
Now run the app and try pointing at the various cubes!

destroying gameObject in both cases in Unity

I have written a code where when the player is not being rendered in camera it should be destroyed but it is being destroyed even being rendered in camera, please see my below code;
using UnityEngine;
public class IfnotvisibleDestroy : MonoBehaviour
{
public SpriteRenderer re;
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
public void Update()
{
if (re.isVisible)
{
Debug.Log(re.isVisible);
}
if(!re.isVisible)
{
Destroy(gameObject);
}
}
}

Do the destroy gameObject part inside the FixedUpdate function

Why the scene DontDestroyOnLoad is staying when switchig back to main menu?

The problem is that when I hit escape to go baco to main menu then I have the dont destroy objects original on the main menu and also the same objects in the DontDestroyOnLoad scene.
I have in the main menu scene 3 objects Player, Game Manager, Scene Loader that each one have attached a script DontDestroy :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DontDestroy : MonoBehaviour
{
private void Awake()
{
if (GameManager.backToMainMenu == false)
{
DontDestroyOnLoad(transform);
}
}
}
In the Game Manager object also attached another script :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class GameManager : MonoBehaviour
{
public SceneLoader sceneLoader;
public PlayerController playerController;
public CamMouseLook camMouseLook;
public static bool backToMainMenu = false;
public static bool togglePauseGame;
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
if (Input.GetKeyDown(KeyCode.P))
{
PauseGame();
}
if (Input.GetKeyDown(KeyCode.Escape))
{
BackToMainMenu();
}
}
public void PauseGame()
{
togglePauseGame = !togglePauseGame;
if (togglePauseGame == true)
{
playerController.enabled = false;
camMouseLook.enabled = false;
Time.timeScale = 0f;
}
else
{
playerController.enabled = true;
camMouseLook.enabled = true;
Time.timeScale = 1f;
}
}
private void BackToMainMenu()
{
sceneLoader.LoadScene(0);
playerController.enabled = false;
camMouseLook.enabled = false;
Cursor.lockState = CursorLockMode.None;
Time.timeScale = 0f;
backToMainMenu = true;
}
}
When I press the escape key it's switching scenes between 1 and 0 and loading scene 0 the main menu.
But then the result is this :
So I pressed escape and back to main menu but the DontDestroyOnLoad also still loaded not removed so I have this 3 objects Player, Game Manager, Scene Loader duplicated.
If I will click on new game again the main menu scene will be remove so there will be no duplication but when back to main menu the DontDestroyOnLoad is stay.

That's exactly what DontDestroyOnLoad it's supposed to do, preserve a GameObject across multiple scenes. Your GameManager script starts with backToMainMenu stetted to false, which will trigger the execution of DontDestroyOnLoad on the Awake function the first time, but not the second (since, when you go back to the main menu, backToMainMenu is setted to true).

Yup, the objects will persists across loading of scenes. That means if there are some already in a scene to begin with there will be multiple ones after loading / reloading a scene.
I deal with by making an Init class & object in every scene, which checks a static variable, and instantiates the objects that are supposed to persist. That way you can start the game from every scene.
class Init {
public static bool hasInstantiatedController = false;
public GameObject GameController;
void Awake() {
if (!hasInstantiatedController) {
hasInstantiatedController = true;
Instantiate (GameController, transform.position, transform.rotation);
}
}
}

Beginner having Problems with Restarting Scenes when Dying in Unity

so I’m trying to create a respawn system as a beginner, and everything seems to be working the first time but the second time it seems to be unbehaving. If anyone knows how to help me, I would appreciate it
LevelControl:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class LevelControl : MonoBehaviour
{
public int index;
public string levelName;
public GameObject GameOverPanel;
public static LevelControl instance;
private void Awake()
{
if (instance == null)
{
DontDestroyOnLoad(gameObject);
instance = GetComponent<LevelControl>();
}
}
void OnTriggerEnter2D(Collider2D other)
{
if (other.CompareTag("Player"))
{
//Loading level with build index
SceneManager.LoadScene(index);
//Loading level with scene name
SceneManager.LoadScene(levelName);
//Restart level
//SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
}
}
public void LoadLevel1()
{
SceneManager.LoadScene("Game");
}
public GameObject GetGameOverScreen()
{
return GameOverPanel;
}
}
PlayerMovement:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerMovement : MonoBehaviour
{
public CharacterController2D controller;
public float runSpeed = 40f;
float horizontalMove = 0f;
bool jump = false;
bool crouch = false;
// Update is called once per frame
void Update()
{
horizontalMove = Input.GetAxisRaw("Horizontal") * runSpeed;
if (Input.GetButtonDown("Jump"))
{
jump = true;
}
if (Input.GetButtonDown("Crouch"))
{
crouch = true;
}
else if (Input.GetButtonUp("Crouch"))
{
crouch = false;
}
}
void FixedUpdate()
{
// Move our character
controller.Move(horizontalMove * Time.fixedDeltaTime, crouch, jump);
jump = false;
//FindObjectOfType<GameManager>().EndGame();
}
void OnCollisionEnter2D(Collision2D collision)
{
if (collision.gameObject.tag == "Enemy")
{
//Destroy(FindObjectOfType<CharacterController2D>().gameObject);
GameObject.Find("Player").SetActive(false);
LevelControl.instance.GetGameOverScreen().SetActive(true);
}
}
}
Error In Unity Video: https://imgur.com/a/Sr0YCWk
If your wondering what I'm trying to do, well, when the 2 colliders of the Player and Enemy collide, I want a restart button to pop up, and the Character to get destroyed, and after that restart the level as is.

You didn't provide much but I try to work with what we have.
In LevelController you have
private void Awake()
{
if (instance == null)
{
DontDestroyOnLoad(gameObject);
instance = GetComponent<LevelControl>();
}
}
First of all just use
instance = this;
;)
Then you are doing
LevelControl.instance.GetGameOverScreenn().SetActive(true);
I don't see your setup but probably GetGameOverScreenn might not exist anymore after the Scene reload while the instance still does due to the DontDestroyOnLoad.
Actually, why even use a Singleton here? If you reload the entire scene anyway you could just setup the references once via the Inspector and wouldn't have to worry about them later after scene changes...
Also
GameObject.Find("Player").SetActive(false);
seems odd .. isn't your PlayerController attached to the Player object anyway? You could just use
gameObject.SetActive(false);

Ok, Normally it would be easier just to do this:
if (collision.gameObject.tag == "Enemy")
{
//Destroy(FindObjectOfType<CharacterController2D>().gameObject);
gameObject.SetActive(false);
LevelControl.instance.GetGameOverScreen().SetActive(true);
But this will NOT work if you want to attach the script to any other gameobjects for any reason. If you are then first make a game object variable containing the player, like this:
public GameObject Player = GameObject.Find("Player");
Then say
Player.SetActive(false);
This creates a player gameobject which you can access by calling the variable.

Coroutine stops working

I have two scripts with a coroutine in them. It works perfectly fine in the first one, but not in the second one, for no apparent reason.
It works in this one:
using System.Collections;
using UnityEngine;
using UnityEngine.UI;
using UnityStandardAssets.ImageEffects;
public class GameStartController : MonoBehaviour {
public Button startButton;
public GameObject cubeSpawner;
// Use this for initialization
private void Start() {
startButton = startButton.GetComponent<Button>();
}
public void StartGame() {
EnableCubeSpawner();
SpawnStartingCubes();
HideStartMenu();
StartCoroutine("FocusCamera");
PlayBackgroundMusic();
}
// Enables the cube spawner, so it can start spawning cubes
private void EnableCubeSpawner() {
cubeSpawner.SetActive(true);
}
private void SpawnStartingCubes() {
cubeSpawner.GetComponent<CubeSpawner>().GenerateStartingCubes();
}
private void PlayBackgroundMusic() {
var audio = GameObject.FindWithTag("Audio").GetComponent<AudioController>();
audio.PlayBackgroundMusic();
}
private void HideStartMenu() {
startButton.transform.parent.GetComponent<CanvasGroup>().interactable = false;
startButton.transform.parent.GetComponent<CanvasGroup>().alpha = 0f;
}
private IEnumerator FocusCamera() {
var camera = GameObject.FindWithTag("MainCamera").GetComponent<Camera>();
var velocity = 0f;
while (Mathf.Abs(camera.GetComponent<DepthOfField>().aperture) > 0.001f) {
Debug.Log(Mathf.Abs(camera.GetComponent<DepthOfField>().aperture));
camera.GetComponent<DepthOfField>().aperture = Mathf.SmoothDamp(camera.GetComponent<DepthOfField>().aperture, 0f, ref velocity, 0.3f);
yield return null;
}
camera.GetComponent<DepthOfField>().aperture = 0f;
}
}
The coroutine works just fine and the camera aperture goes smoothly from 0.6 to 0.
However in the second script this doesn't happen:
using System.Collections;
using System.Linq;
using UnityEngine;
using UnityStandardAssets.ImageEffects;
public class GameOverController : MonoBehaviour {
public void EndGame() {
StartCoroutine("UnfocusCamera");
DisableCubeSpawner();
DestroyAllCubes();
StopBackgroundMusic();
ShowStartMenu();
}
// Disables the cube spawner, so it can stop spawning cubes
private void DisableCubeSpawner() {
var cubeSpawner = GameObject.FindWithTag("CubeSpawner");
cubeSpawner.SetActive(false);
}
private void DestroyAllCubes() {
var gameObjects = FindObjectsOfType(typeof(GameObject));
foreach (var gameObject in gameObjects.Where(gameObject => gameObject.name.Contains("Cube"))) {
Destroy(gameObject);
}
}
private void StopBackgroundMusic() {
var audio = GameObject.FindWithTag("Audio").GetComponent<AudioController>();
audio.StopBackgroundMusic();
}
private void ShowStartMenu() {
var startMenu = GameObject.FindWithTag("StartMenu");
startMenu.GetComponent<CanvasGroup>().interactable = true;
startMenu.GetComponent<CanvasGroup>().alpha = 1f;
}
private IEnumerator UnfocusCamera() {
var camera = GameObject.FindWithTag("MainCamera").GetComponent<Camera>();
var velocity = 0f;
while (camera.GetComponent<DepthOfField>().aperture < 0.6f) {
Debug.Log(Mathf.Abs(camera.GetComponent<DepthOfField>().aperture));
camera.GetComponent<DepthOfField>().aperture = Mathf.SmoothDamp(camera.GetComponent<DepthOfField>().aperture, 0.6f, ref velocity, 0.3f);
yield return null;
}
// camera.GetComponent<DepthOfField>().aperture = 0f;
}
}
It only works for one frame (aperture goes from 0 to 0.03), and then just stops.
Why is this happening?

If you destroy (or disable) a game object, coroutines running on components attached to it will stop. I'm unable to find a primary source on this, but here are two other stack overflow questions where this was the problem:
Unity3d coroutine stops after while-loop
Unity - WaitForSeconds() does not work
The coroutine stops because the GameObject your GameOverController is attached to is destroyed. Presumably Unity checks whether an object still exists before resuming its coroutine, and if the object is destroyed, Unity does not continue to execute it.
To fix this problem, you can delay destroying the GameObject until the animation is complete (perhaps putting the destroy code after the while loop in the coroutine) or put the component on a GameObject that won't be destroyed.

In most cases this mean that your object or script became inactive. Best way to check this is to add OnDisable() method to your script and call logging from it