Develop Reference

IEnumerator script is not working and Coroutine is not running? Unity,C#

I am writing a script for Enemy in my game, where they will attack hero using Coroutine at a certain interval. Though, while running the game, Enemy is not attacking. I have created two events for enemy animation specific for attack. The IE numerator part of code is not running. Can anyone tell what is going wrong?
I wrote Debug.Log("Hello"), to verify if it executes but it doesn't print.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class EnemyAttack : MonoBehaviour
{
[SerializeField] private float range = 3f;
[SerializeField] private float timeBetweenAttacks = 1f;
private Animator anim;
private GameObject player;
private bool playerInRange;
private BoxCollider[] weaponColliders;
// Start is called before the first frame update
void Start()
{
weaponColliders = GetComponentInChildren <BoxCollider[]> ();
player = GameManager.instance.Player;
anim = GetComponent <Animator> ();
StartCoroutine (attack());
}
// Update is called once per frame
void Update()
{
if(Vector3.Distance(transform.position,GameManager.instance.Player.transform.position) < range)
{
playerInRange = true;
}else{
playerInRange = false;
}
}
public IEnumerator attack()
{
Debug.Log("Hello");
if(playerInRange && !GameManager.instance.GameOver)
{
anim.Play("Attack");
yield return new WaitForSeconds(timeBetweenAttacks);
}
yield return null;
StartCoroutine(attack());
}
public void EnemyBeginAttack(){
foreach(var weapon in weaponColliders){
weapon.enabled = true;
}
}
public void EnemyEndAttack(){
foreach(var weapon in weaponColliders){
weapon.enabled = false;
}
}
}

The issue is likely the code weaponColliders = GetComponentInChildren<BoxCollider[]>();. GetComponentInChildren should only be called with component types (or interface types), but BoxCollider[] is an array type.
You should instead use GetComponentsInChildren<BoxCollider>();.

Why doesn't "OnTriggerEnter2D()" work when two specific objects collide?

I am creating this flappy bird style game in unity with C#.
I have a scored function in the Game Controller script. Here it is...
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;
public class GameController : MonoBehaviour
{
private int score = 0;
public float starScrollSpeed;
public float groundScrollSpeed;
public float skyScrollSpeed;
public GameObject gameOverText;
public GameObject playAgain;
public bool gameOver = false;
public static GameController instance;
public Text scoreText;
// Start is called before the first frame update
void Awake()
{
if(instance == null)
{
instance = this;
}
else if(instance != this)
{
Destroy(gameObject);
}
}
// Update is called once per frame
void Start()
{
}
void Update()
{
}
public void BirdScored()
{
if (gameOver)
{
return;
}
score++;
scoreText.text = "SCORE " + score.ToString();
}
public void PlaneDestroyed()
{
gameOverText.SetActive(true);
playAgain.SetActive(true);
gameOver = true;
}
}
Actually Bird and Plane is the same thing.
What I want to do is to make the bird score/run the BirdScored() function when the Plane overlaps with a star. The Plane has a Rigidbody2D and a collider and stars have a Rigidbody2D but no collider because In the bird script if the plane collide, it destroys.
Here is the Bird Script
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Bird : MonoBehaviour
{
private bool isDead = false;
private Rigidbody2D rb2d;
public float upforce = 200f;
private Animator anim;
// Start is called before the first frame update
void Start()
{
rb2d = GetComponent<Rigidbody2D>();
anim = GetComponent<Animator>();
}
// Update is called once per frame
void Update()
{
if (isDead == false)
{
if (Input.GetMouseButtonDown(0))
{
rb2d.velocity = Vector2.zero;
rb2d.AddForce(new Vector2(0, upforce));
}
}
anim.SetTrigger("Flap");
}
void OnCollisionEnter2D()
{
isDead = true;
anim.SetTrigger("Die");
GameController.instance.PlaneDestroyed();
}
}
And here is the star script...
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Stars : MonoBehaviour
{
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
}
public void OnTriggerEnter2D(Collider2D other)
{
if (other.gameObject.name == "Plane")
{
GameController.instance.BirdScored();
}
}
}
What is wrong and what should I do?

Put a Colider2D on the star, and check the Is Trigger option in the inspector.
The Is Trigger is disable the collision with any other collider2d so your plane wont be destroyed by the OnCollisionEnter2D, but the OnTriggerEnter2D will trigger properly.

I can see in your screenshot that the collider isn't set to "is trigger", which makes it unable to register trigger collisions.

Next Scene Not Loading

My problem is that when all the enemies are killed the scene that should be loaded is not loading. I did add the scene to the Build setting (it has an index of 3) but it is still not loading. The script I created is attached to an empty object and not directly to the sprite (is that okay?). Can someone tell me why the scene isn't loading? Thank you.
This image is for to show you the EnemySpawner empty object inspector
EnemySpawner Script :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class EnemySpawner : MonoBehaviour {
[SerializeField] GameObject EnemyPreFab;
[SerializeField] int MaxEnemies = 30;
[SerializeField] float EnemySpawnTime = 1.00001f;
[SerializeField] GameObject FirstWaypoint;
int CurrentNumOfEnemies = 0;
public LevelManager myLevelManager;
public int maximumnumberofhits = 0;
int timesEnemyHit;
IEnumerator SpawningEnemies()
{
while(CurrentNumOfEnemies <= MaxEnemies)
{
GameObject Enemy = Instantiate(EnemyPreFab, this.transform.position, Quaternion.identity);
CurrentNumOfEnemies++;
yield return new WaitForSeconds(EnemySpawnTime);
}
}
void Start()
{
StartCoroutine(SpawningEnemies());
timesEnemyHit = 0;
if (this.gameObject.tag == "EnemyHit")
{
CurrentNumOfEnemies++;
}
}
void OnCollisionEnter2D()
{
timesEnemyHit++;
if (timesEnemyHit == maximumnumberofhits)
{
CurrentNumOfEnemies--;
Destroy(this.gameObject);
}
if (CurrentNumOfEnemies == 0)
{
myLevelManager.LoadLevel("NextLevelMenu");
Debug.Log("LevelLoaded");
}
}
}
LevelManger 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);
}
}
EnemyShooting Script :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class EnemyShooting : MonoBehaviour {
[SerializeField] float EnemyLaserSpeed = 10f;
[SerializeField] float EnemyLaserFireTime;
[SerializeField] GameObject LaserBulletEnemyPreFab;
[SerializeField] int MaxNumberOfHits = 1;
int CurrentNumberOfHits = 0;
Coroutine FireCoroutine;
void OnTriggerEnter2D(Collider2D collider)
{
if(collider.gameObject.tag == "PlayerLaser")
{
if(CurrentNumberOfHits < MaxNumberOfHits)
{
CurrentNumberOfHits++;
Destroy(collider.gameObject);
Score.ScoreValue += 2;//The user will be rewarded 1 point
}
}
}
void DestroyEnemy()
{
if(CurrentNumberOfHits >= MaxNumberOfHits)
{
Destroy(gameObject);
}
}
private void Fire()
{
FireCoroutine = StartCoroutine(ShootContinuously());
}
void BecomeVisible()
{
Fire();
}
IEnumerator ShootContinuously()
{
while (true)
{
GameObject LaserBulletEnemy = Instantiate(LaserBulletEnemyPreFab, this.transform.position, Quaternion.identity) as GameObject;
LaserBulletEnemy.GetComponent<Rigidbody2D>().velocity = new Vector2(0, EnemyLaserSpeed);
EnemyLaserFireTime = Random.Range(0.5f, 0.9f);
yield return new WaitForSeconds(EnemyLaserFireTime);
}
}
// Use this for initialization
void Start () {
BecomeVisible();
}
// Update is called once per frame
void Update () {
DestroyEnemy();
}
}
EnemyPathing script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class EnemyPathing : MonoBehaviour {
[SerializeField] List<Transform> WayPoints;
[SerializeField] float EnemyMovingSpeed = 5f;
int WayPointIndex = 0;
void EnemyMoving()
{
if (WayPointIndex <= WayPoints.Count - 1)
{
var TargetedPosition = WayPoints[WayPointIndex].transform.position; //The position of where the enemy needs to go
TargetedPosition.z = 0f;
var MoveThisFrame = EnemyMovingSpeed * Time.deltaTime;
transform.position = Vector2.MoveTowards(this.transform.position, TargetedPosition, MoveThisFrame);
if(transform.position == TargetedPosition)
{
WayPointIndex++;
}
}
else
{
Destroy(gameObject);
}
}
// Use this for initialization
void Start () {
transform.position = WayPoints[WayPointIndex].transform.position;
}
// Update is called once per frame
void Update () {
EnemyMoving();
}
}

Problem
You're checking for collisions on the SPAWNER; when someone hits the Spawner it counts down enemies. But the Spawner doesn't have a collision box in the screenshot so it can never be hit. The Scene changing code can never be called.
So the game, based on the code, looks like this:
Spawn X enemies,
Hit the Spawner X times,
(Removed: Destroy the Spawner,)
Change scene.
I'm guessing this is conceptually incorrect and you actually want to check collisions on the spawned enemies, which will then count up the amount of destroyed enemies, and change the scene when they are all dead.
Solution
Conceptually, what you want is:
Spawn X enemies
Count up variable for every enemy
On Enemy death, count it down
When 0, change scene
So how do we code this?
Well, every enemy needs a reference to the object that holds the count. You can do this in several ways, when I personally do it I usually have just one spawner that is responsible for everyone so I make that one a Singleton, that can be references from anywhere:
EnemySpawner
public class EnemySpawner : MonoBehaviour
{
public static Spawner Instance = null;
int CurrentNumOfEnemies = 0;
// ... etc
void Start()
{
if (Instance == null)
Instance = this;
// Spawn enemies like you do already, CurrentNumOfEnemies++ for every spawned
}
public OnEnemyDeath() {
CurrentNumOfEnemies--;
if (CurrentNumOfEnemies < 1)
{
// You killed everyone, change scene:
LevelManager.LoadLevel("Your Level");
}
}
}
Enemy script (I don't know how your current code looks, but here's a minimal solution based on how I THINK your code looks):
void OnDestroy()
{
// This will run automatically when you run Destroy() on this gameObject
EnemySpawner.Instance.OnEnemyDeath(); // Tell the EnemySpawner that someone died
}
This will only work if you have exactly only ONE spawner. If you have multiple ones you will have to send a reference to the instance of its spawner to every spawned enemy. I can show you how to do ths too, if you wish.
Bonus content
LevelManager doesn't need to be on a GameObject, it can be static instead:
Remove the LevelManager script from any GameObject
Change your LevelManager code to this:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public static class LevelManager
{
public static void LoadLevel(string name)
{
Debug.Log("Level loading requested for" + name);
SceneManager.LoadScene(name);
}
}
Now you can use it from ANYWHERE, without needing to initialize a reference to any script or GameObject:
LevelManager.LoadLevel("My Level");

myLevelManager.LoadLevel("NextLevelMenu"); is never executed, because you destroy the object in the if-test above.

Displaying score in another scene on Unity

In the game I am creating a 'Game Over' scene which loads once the player loses the game. During the game, the score is counted by the player's position on the screen and increases as the player's y-axis position increases.
I used this code to display the score on the scene the game was actually played:
using UnityEngine;
using UnityEngine.UI;
public class PlayerScore : MonoBehaviour
{
public Transform player;
public Text scoreText;
// Update is called once per frame
void Update()
{
scoreText.text = player.position.y.ToString("0");
}
}
I tried to use the same coding to display the final score of the player on the 'Game Over' screen. The problem I faced was that I was not able to identify the player on the 'Game Over' scene as the player was not an object or sprite on that scene.
Is there an easy way to reference the player sprite from the previous scene into the final ('Game Over') scene so I can use it to determine the final score?
This is the script I tried with a game object of the 'EndScene' within the playing scene:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;
public class EndMenu: MonoBehaviour
{
public Text scoreText;
public Transform player;
public static bool GameEnds = false;
public GameObject endMenuUI;
void OnCollisionEnter2D(Collision2D exampleCol)
{
if(exampleCol.collider.tag == "Obstacle")
{
endMenuUI.SetActive(true);
Time.timeScale = 0.0001f;
GameEnds = true;
}
}
public void Retry()
{
SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex - 1);
}
public void BackToMenu()
{
SceneManager.LoadScene("Menu");
}
public void Quit()
{
Debug.Log("Quitting game...");
Application.Quit();
}
// Update is called once per frame
void Update()
{
scoreText.text = player.position.y.ToString("0");
}
}

You can keep the player using DontDestroyOnLoad
You could add this to the player:
void Awake() {
DontDestroyOnLoad(transform.gameObject);
}
You could do other stuff like keeping just the data... but the easier way should be this one.
Keep in mind that the player will remain in you gameover screen.
In my opinion the best idea could be creating a new gameobject in your game scene called "GameOverScreen" and disable it until you need it.

I think the easiest solution would be to simply store the score as a static variable that will persist across scene loads, then manually reset it when you start over. For example:
public class PlayerScore : MonoBehaviour
{
public Transform player;
public Text scoreText;
public static string scoreString;
// Update is called once per frame
void Update()
{
scoreString = player.position.y.ToString("0");
scoreText.text = scoreString;
}
}
Now you will be able to access scoreString from anywhere in your code and it will be whatever it was when the PlayerScore component last ran its Update(). Then in your EndMenu class, you would simply update your Retry() and BackToMenu() methods like so:
public void Retry()
{
PlayerScore.scoreString = "0";
SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex - 1);
}
public void BackToMenu()
{
PlayerScore.scoreString = "0";
SceneManager.LoadScene("Menu");
}
And your EndMenu.Update() method becomes the following:
// Update is called once per frame
void Update()
{
scoreText.text = PlayerScore.scoreString;
}

//try to use playerprefs to save the score
public class PlayerScore : MonoBehaviour
{
public Transform player;
public Text scoreText;
// Update is called once per frame
void Update()
{
scoreText.text = player.position.y.ToString("0");
PlayerPrefs.SetInt("CurrentScore", player.position.y);
}
}
//for another scene get the value of saved score using playerprefs.getInt
public class EndMenu: MonoBehaviour
{
public Text scoreText;
public Transform player;
public static bool GameEnds = false;
public GameObject endMenuUI;
void OnCollisionEnter2D(Collision2D exampleCol)
{
if(exampleCol.collider.tag == "Obstacle")
{
endMenuUI.SetActive(true);
Time.timeScale = 0.0001f;
GameEnds = true;
}
}
public void Retry()
{
SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex - 1);
}
public void BackToMenu()
{
SceneManager.LoadScene("Menu");
}
public void Quit()
{
Debug.Log("Quitting game...");
Application.Quit();
}
// Update is called once per frame
void Update()
{
scoreText.text = PlayerPrefs.GetInt("Score",0);
}
}

Making a sliding door that is unlocked with a key in unity

I've been trying to make a sliding door for my unity level and I've managed to set up the animations but the scripting that's supposed to link up the functions with the objects isn't working.
Here's the script for the key card:
using UnityEngine;
using System.Collections;
public class Key_Pickup_1 : MonoBehaviour {
public GameObject player;
private Player_inventory playerinventory;
void Awake ()
{
playerinventory = player.GetComponent<Player_inventory>();
}
// Update is called once per frame
void onTriggerEnter()
{
if (gameObject == player)
{
playerinventory.hasKey_1 = true;
Destroy(gameObject);
}
}
}
Here's the script for the Door animation:
using UnityEngine;
using System.Collections;
public class Door_Animation_1 : MonoBehaviour {
public string Open;
private Animator anim_1;
public GameObject player;
private Player_inventory playerInventory;
void Start()
{
anim_1 = GetComponent<Animator>();
player = GameObject.FindGameObjectWithTag("Player");
playerInventory = player.GetComponent<Player_inventory>();
}
void OntriggerEnter (Collider other)
{
if(other.gameObject == player)
{
if (playerInventory.hasKey_1)
{
anim_1.SetTrigger(Open);
}
}
}
Any Ideas?

You don't have the proper capitalization for the OnTriggerEnter methods in your code. You have two different spellings and they are both wrong. It must be exactly OnTriggerEnter (or OnTriggerEnter2D for objects with a Collider2D instead of a Collider).