Load next level if amount of enemies is zero - c#

This is my first time making a 2d game. I'm trying to load a scene if the amount of objects with tag "Enemy" is zero. Line 22 doesn't seem to work. I don't get any errors.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class LevelLoader : MonoBehaviour
{
public Animator transition;
public float transitionTime;
public GameObject enemyPrefab;
public GameObject[] enemy;
// Update is called once per frame
void Update()
{
if (enemy == null)
{
enemy = GameObject.FindGameObjectsWithTag("Enemy");
Debug.Log("null!");
LoadNextLevel();
}
}
public void LoadNextLevel()
{
StartCoroutine(LoadLevel(SceneManager.GetActiveScene().buildIndex + 1));
}
IEnumerator LoadLevel(int levelIndex)
{
transition.SetTrigger("Start");
yield return new WaitForSeconds(transitionTime);
SceneManager.LoadScene(levelIndex);
}
}
enemy = GameObject.FindGameObjectsWithTag("Enemy");

Initially enemy is null.
So, in the first frame (the first time Update() is called) it satisfies the if condition and then assign something to enemy.
Then, in the second and later frames, enemy is not null anymore, so it does not satisfies if (enemy == null) condition and the lines in the if statement does not be executed. It means that, the lines enemy = GameObject.FindGameObjectsWithTag("Enemy") and LoadNextLevel(); will never be executed after the first frame.
My suggestion is that rewrite the Update() just like this:
void Update() {
enemy = GameObject.FindGameObjectsWithTag("Enemy"); // get "Enemies" first
// then do something by using it
if (enemy == null) {
Debug.Log("null!");
LoadNextLevel();
}
}

So, I solved the question. The problem was that the condition was before assigning the variable.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class LevelLoader : MonoBehaviour
{
public Animator transition;
public float transitionTime;
// Update is called once per frame
void Update()
{
GameObject[] enemy = GameObject.FindGameObjectsWithTag("Enemy");
if (enemy == null || enemy.Length == 0)
{
LoadNextLevel();
}
//Debug.Log(GameObject.FindGameObjectsWithTag("Enemy"));
}
public void LoadNextLevel()
{
StartCoroutine(LoadLevel(SceneManager.GetActiveScene().buildIndex + 1));
}
IEnumerator LoadLevel(int levelIndex)
{
transition.SetTrigger("Start");
yield return new WaitForSeconds(transitionTime);
SceneManager.LoadScene(levelIndex);
}
}

I believe that it's because the variable enemy is of type array and not a list. Arrays are more difficult to deal with and are of a fixed size.
Instead, consider using a List:
List<GameObject> enemy = new List<GameObject>();
Here are some additional resources to assist you with understanding the difference between arrays and lists.
https://www.w3schools.com/cs/cs_arrays.php
https://www.c-sharpcorner.com/article/c-sharp-list/
The difference/when to use each
Array versus List<T>: When to use which?
https://csharp-station.com/c-arrays-vs-lists/
https://www.educba.com/c-sharp-array-vs-list/

Related

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!

Unity3D Shooter: Using tags to switch level after killing all enemies

I am new to Unity and was trying, after some suggestions, to use tags to know the number of enemies i have in each level and move to the next scene right after eliminating all enemies. This is the script i use on enemy gameobjects. I've also tagged each of them with the "enemy" tag in unity inspector but it still doesn't work when i run the game. After killing all the enemies, it didnĀ“t change to next scene (Success!). Any ideas on what I'm doing wrong? Any other suggestions?
Thanks a lot for the help.
Enemies Script
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class BadguyScript : MonoBehaviour
{
public GameObject[] enemies;
public int maxHealth;
public int curHealth;
private Animator myAnimator;
private bool isDead;
[SerializeField]
private float DespawnTime = 2.5f;
[SerializeField]
private string DeathAnimHash = "isDead";
void Start()
{
myAnimator = GetComponent<Animator>();
myAnimator.enabled =true;
myAnimator.SetBool (DeathAnimHash ,isDead);
maxHealth = 1;
curHealth = maxHealth;
}
void Update()
{
if (curHealth < 1)
{
isDead = true;
myAnimator.SetBool (DeathAnimHash ,isDead);
Destroy(gameObject,DespawnTime);
}
enemies = GameObject.FindGameObjectsWithTag("enemy"); // Checks if enemies are available with tag "Enemy".
if (enemies.Length == 0)
{
SceneManager.LoadScene("SucessScene"); // Load the scene with name "SucessScene"
}
}
void OnTriggerEnter2D(Collider2D col)
{
if (isDead)
return;
if (col.tag == "bullet")
{
curHealth -= 1;
Destroy(col.gameObject);
}
}
}
I would create a script holder gameobject for this and put a GameManager script inside it. And inside GameManager.cs which should be a singleton class you can have a property like this:
int _enemyNumber;
public int EnemyNumber{
get{
return _enemyNumber;
}
set{
_enemyNumber = value;
}
}
And when you need to change these values, use some functions you will create inside this game controller such as:
public void DecreaseEnemyCount(){
//do the logic here
}
public void SetEnemyCount(){
//do the logic here
}
Also you can find information about creating a singleton class here
You create a list with all enemies, its a good practice, cause you'll gain performance. But you're verifing if enemies.Lenght == 0, what will never occur, because before you are adding the gameObject in the list enemies = GameObject.FindGameObjectsWithTag("enemy");
In the start method, you can search for all enemies and add then in your array, and in the update or onTriggerEnter you remove it from your array and validate the array lenght. I think it'll be more easy.
Instead of adding the script to a new gameManager script attached to an empty game object cause now once all enemies are killed the script will not be in work but if added to an empty gameobject it will be working always.

Next Scene not loading when requested to

I have created a game where when the user breaks all the blocks he is taken to the next scene but this is not happening despite adding all of the scenes I have in the build settings. I have no errors whatsoever and the scene is written correctly. Can someone help me resolve this, please?
This is the build settings
Bricks script : (where the scene is called)
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Bricks : MonoBehaviour {
public LevelManager myLevelManager;
public static int brickCount = 0;
public int maxNumberOfHits = 0;
int timesHit;
public AudioClip BlockBreaking;
// Use this for initialization
void Start () {
timesHit = 0;
if(this.gameObject.tag == "BrickHit")
{
brickCount++;
}
if(this.gameObject.tag == "BrickHitTwice")
{
brickCount++;
}
}
void OnCollisionEnter2D()
{
timesHit++;
if (timesHit == maxNumberOfHits)
{
brickCount--;
Destroy(this.gameObject);
}
if(brickCount == 0)
{
myLevelManager.LoadLevel("Level1.2"); //THIS SCENE IS NOT LOADING
}
if(this.gameObject.tag == "BrickHit") //If the gameObject (Block One Point) with the tag "BrickHit" is hit
{
Scores.scoreValue += 1;//The user will be rewarded 1 point
AudioSource.PlayClipAtPoint(BlockBreaking, transform.position);
}
if(this.gameObject.tag == "BrickHitTwice") //If the gameObject (Block Two Points) with the tag "BrickHitTwice" is hit
{
Scores.scoreValue += 2; //The user will be rewarded 2 points
AudioSource.PlayClipAtPoint(BlockBreaking, transform.position);
}
}
LevelManager Script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class LevelManager : MonoBehaviour {
public void LoadLevel(string name)
{
print("Level loading requested for" + name);
SceneManager.LoadScene(name);
}
I suspect that your bug may lie in the fact that you're Destroy()ing the gameObject before it can load the next scene; you get a race condition on what will finish first; LoadScene or Destroy() - which would explain why it sometimes work. You should never assume it is a bug in the framework before understanding your problem.
Try putting the Destroy() after the LoadScene() or with a delay to understand if this is your issue.
Also, your LevelManager can be made static and doesn't need to inherit from MonoBehaviour since it doesn't use gameObject functionality.
public static class LevelManager {
public static void LoadLevel(string name)
{
print("Level loading requested for" + name);
SceneManager.LoadScene(name);
}
}
Used by doing LevelManager.LoadLevel("MyLevel");, but then you may question what is more effective, doing LevelManager.LoadLevel or SceneManager.LoadLevel, as they will do the exact same thing.
The main issue that you're having is not having a single source to check brickCount instead each individual brick is maintaining its own count. I would recommend moving the brick counting logic into a separate class. It would seem like LevelManager would a good place for it. So in LevelManager add:
private int brickCount = 0;
public void AddBrick()
{
brickCount++;
}
public void RemoveBrick()
{
brickCount--;
// Check if all bricks are destroyed
if (brickCount == 0)
{
LoadLevel("Level1.2");
}
}
And then in your brick script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Bricks : MonoBehaviour {
public LevelManager myLevelManager;
public int maxNumberOfHits = 0;
int timesHit;
public AudioClip BlockBreaking;
// Use this for initialization
void Start () {
timesHit = 0;
myLevelManager.AddBrick();
// I'm not sure why you were checking the tag here, since the result was the same
}
void OnCollisionEnter2D()
{
timesHit++;
if (timesHit == maxNumberOfHits)
{
myLevelManager.RemoveBrick();
Destroy(this.gameObject);
}
/* This looks like the player is getting score whether the brick is destroyed or not. Also, it would appear the player won't get scored on the final brick */
if(this.gameObject.tag == "BrickHit") //If the gameObject (Block One Point) with the tag "BrickHit" is hit
{
Scores.scoreValue += 1;//The user will be rewarded 1 point
AudioSource.PlayClipAtPoint(BlockBreaking, transform.position);
}
if(this.gameObject.tag == "BrickHitTwice") //If the gameObject (Block Two Points) with the tag "BrickHitTwice" is hit
{
Scores.scoreValue += 2; //The user will be rewarded 2 points
AudioSource.PlayClipAtPoint(BlockBreaking, transform.position);
}
}
}

Unity3D C# code to teleport

I want my player to teleport to a GameObject location When I get 7 points.
When I pick up my item and my points change to 7 I want my player to teleport to GameObject's location (Cube) Here is the script C#
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class FpsScoreScript : MonoBehaviour
{
public int points;
public Transform Destination;
public void Start()
{
}
public void Update()
{
if (points == 7)
{
//teleport code here
}
}
}
How do it get it to work. I want to be teleported to the object that is linked to the "public Transform Destination;" Thanks for the answers.
Its true that your player will not move because of the check you had put in the update() function. Now this is the code that will make your player teleport.
Theory:
The code has a private bool isTeleported and a private function Teleport(). In the update function we will check if the points are equal to 7 and isTeleported is false and then call Teleport() function. And there we will set isTeleported to true so that the check in the update() function becomes false so the player will not teleport.
public class FpsScoreScript : MonoBehaviour
{
public int points;
public Transform Destination;
bool isTeleported = false;
public void Update()
{
if (points == 7 && !isTeleported)
{
Teleport();
}
}
void Teleport(){
isTeleported = true;
player.transform.position = destination.transform.position;
}
Simply set your current object's position to Destination's position.
gameObject.transform.position = Destination.position;
However if you put this directly in:
if (points == 7)
{
gameObject.transform.position = Destination.position;
}
You are going to get teleported to the cube forever since your points have not changed and Update is called every frame. You will need to have something to prevent that, like resetting points to 0, for example.
You Might Not Be Able to Move The Player Since Your Player Is Stuck In The Ground. Is That The Case? BTW, Here's The Final Fixed Code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class FpsScoreScript : MonoBehaviour
{
public int points;
public Transform destination;
public bool teleported;
public void Start()
{
}
public void Update()
{
if (points == 7 && !teleported)
{
gameObject.transform.position = destination.position;
teleported = true;
}
}
}

Instantiate a prefab?

I am making a crossy road game with 4 prefab "chunks" that I want to create when the player touches the collider named . My code randomizes which chunk is loaded when the player hits it and then spawns the next chunk. For some reason though, it doesn't recognize my prefab and I want to load the chunk 25 z-value ahead of the last one. Code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class ChunkLoader : MonoBehaviour {
int level = 0;
public Transform chickenpos;
// Use this for initialization
void Start () {
}
// Update is called once per frame
void Update () {
}
void spawnChunk()
{
float chunkload = Random.Range(0, 2);
Debug.Log(chunkload);
if (level <= 10)
{
if(chunkload <= 1 )
{
Instantiate (ChunkA1, chickenpos);
}
}
}
void OnTriggerEnter(Collider other)
{
if (other.tag == "Loader")
{
level = level++;
Debug.Log(level);
spawnChunk();
}
}
}
You first need to declare a variable for your prefab - I will assume it is of type Gameobject here.
int level = 0;
public Transform chickenpos;
public Gameobject ChunkA1; //declare variable for the prefab
// Use this for initialization
void Start () {}
You can then either drag the prefab in your Assets folder to the field in the inspector, or locate it through your script using Resources.Load().

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