I made a script that shoots a bullet and destroys it after 3 seconds, however it destroys the original bullet after it is shot which makes unity unable to make copies of it to shoot another bullet, An okay solution might be to make a copy of the bullet and shoot the copy however I do not know how to do that.
This is the script for the gun
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class GunShootingScript : MonoBehaviour
{
public ParticleSystem MuzzleFlash;
public float damage = 10f;
public float range = 100f;
public GameObject bulletPrefab;
public float bulletLife = 3f;
public Camera playerCamera;
private void Update()
{
if(Input.GetKeyDown(KeyCode.Mouse0))
{
Destroy(bulletPrefab, bulletLife);
Shoot();
}
}
void Shoot()
{
MuzzleFlash.Play();
Instantiate(bulletPrefab, playerCamera.transform.position, playerCamera.transform.rotation);
RaycastHit hit;
if(Physics.Raycast(playerCamera.transform.position, playerCamera.transform.forward, out hit, range))
{
TakeDamage target = hit.transform.GetComponent<TakeDamage>();
if(target != null)
{
target.GiveDamage(damage);
}
}
}
}
This is the script for the bullet.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Shot : MonoBehaviour
{
// Start is called before the first frame update
public float speed = 3000f;
void Update()
{
transform.position += transform.forward * speed * Time.deltaTime;
}
}
From what I see, you destroy the bulletPrefab but you never actually assign an object for it. You can have a separate GameObject and do that when instantiating inside the Shoot method. Try this:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class GunShootingScript : MonoBehaviour
{
public ParticleSystem MuzzleFlash;
public float damage = 10f;
public float range = 100f;
public GameObject bulletPrefab;
public float bulletLife = 3f;
private GameObject bulletShot // This is what I added
public Camera playerCamera;
private void Update()
{
if(Input.GetKeyDown(KeyCode.Mouse0))
{
Destroy(bulletShot); // Removed the timer from here
Shoot();
}
}
void Shoot()
{
MuzzleFlash.Play();
bulletShot = Instantiate(bulletPrefab, playerCamera.transform.position, playerCamera.transform.rotation); // Assigned the bullet to the separate GameObject
RaycastHit hit;
if(Physics.Raycast(playerCamera.transform.position, playerCamera.transform.forward, out hit, range))
{
TakeDamage target = hit.transform.GetComponent<TakeDamage>();
if(target != null)
{
target.GiveDamage(damage);
}
}
}
}
That way, when you try to destroy it, there will actually be something to destroy. However, this will create a new issue. The previously instantiated object will be destroyed instantly when you shoot again. You can fix that by creating a list and adding the bullets there. However, that is NOT efficient. And since you are going to start all over, I suggest you go for an Object Pool. What is that? Glad you asked!
There is a very good video by Jason Weimann on YouTube about object pooling. You might want to give it a go, it is old but definitely not outdated.
https://www.youtube.com/watch?v=uxm4a0QnQ9E
You might need to keep a reference to the shot bullet, to be able to destroy with a coroutine after 3 seconds, it later on like this:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class GunShootingScript : MonoBehaviour
{
public ParticleSystem MuzzleFlash;
public float damage = 10f;
public float range = 100f;
public GameObject bulletPrefab;
public float bulletLife = 3f;
private Queue<GameObject> myQ = new Queue<GameObject>(); //queue to keep track of the shot bullet and handle the delayed destroy
private IEnumerator coroutine;
void Start() {
coroutine = DelayedDestroy(3f);
}
public Camera playerCamera;
private void Update()
{
if(Input.GetKeyDown(KeyCode.Mouse0))
{
//Destroy(bulletPrefab, bulletLife); Commented to avoid immediate destruction
Shoot();
}
}
void Shoot()
{
MuzzleFlash.Play();
myQ.Enqueue(Instantiate(bulletPrefab, playerCamera.transform.position, playerCamera.transform.rotation));
RaycastHit hit;
if(Physics.Raycast(playerCamera.transform.position, playerCamera.transform.forward, out hit, range))
{
TakeDamage target = hit.transform.GetComponent<TakeDamage>();
if(target != null)
{
target.GiveDamage(damage);
}
}
StartCoroutine(coroutine);
}
private IEnumerator DelayedDestroy(float waitTime) {
yield return new WaitForSeconds(waitTime);
GameObject nullcheck = myQ.Dequeue();
if (nullcheck != null) { //in case the queue is empty
Destroy(nullcheck );
}
}
}
Did not debug that, it is to give you the idea. You can check the Queue data structure and coroutines.
Check pooling to achieve what you are making even better :)
Related
I have a problem with writing a function that throws spawned ball by pressing a button.
So far, i could only instantiate the ball and it is affected by gravity.
I can not wrap my head arround, how in my code should i add a force to push it with some force. Right now it just plops in front of a player.
I tried to fiddle with .AddForce() on a ball rigidbody2D and still nothing.
I would greatly appreciate if someone could take a look at the code and guide me into some directcion on where to AddForce for ball to make it move?
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.InputSystem;
public class PlayerControl : MonoBehaviour
{
[Header("Player Atributes")]
[SerializeField] float runSpeed = 10f;
Vector2 moveInput;
Rigidbody2D playerRigidbody2D;
[Header("Ball Settings")]
public bool playerHasABall = false;
[SerializeField] GameObject ball;
[SerializeField] Transform ballSpawn;
void Start()
{
playerRigidbody2D = GetComponent<Rigidbody2D>();
}
void Update()
{
Run();
FlipSprite();
}
void OnMove(InputValue value)
{
moveInput = value.Get<Vector2>();
}
void OnFire(InputValue value)
{
if(!playerHasABall) {return;}
Instantiate(ball, ballSpawn.position, transform.rotation);
playerHasABall = false;
}
void Run()
{
Vector2 playerVelocity = new Vector2 (moveInput.x * runSpeed, playerRigidbody2D.velocity.y);
playerRigidbody2D.velocity = playerVelocity;
}
void FlipSprite()
{
bool playerHasHorizontalSpeed = Mathf.Abs(playerRigidbody2D.velocity.x) > Mathf.Epsilon;
if (playerHasHorizontalSpeed)
{
transform.localScale = new Vector2 (Mathf.Sign(playerRigidbody2D.velocity.x), 1f);
}
}
//Ball picking up script. It destroys the ball with a tag "Ball" and sets a bool playerHasABall to true
private void OnTriggerEnter2D(Collider2D other)
{
if(other.tag == "Ball")
{
Destroy(other.gameObject);
playerHasABall = true;
}
}
}
So, i manage to fiddle with the .AddForce() method once again and i came up with a solution to my problem.
My OnFire script looks like this:
void OnFire(InputValue value)
{
if(!playerHasABall) {return;}
Instantiate(ball, ballSpawn.position, transform.rotation);
playerHasABall = false;
}
No change here. I made another script called "BallBehaviour.cs" and added it to the ball with a code like this:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class BallBehaviour : MonoBehaviour
{
[SerializeField] float ballForce = 20f;
PlayerControl player;
void Start()
{
player = FindObjectOfType<PlayerControl>();
Throw();
}
public void Throw()
{
GetComponent<Rigidbody2D>().AddForce(player.transform.localScale * ballForce, ForceMode2D.Impulse);
}
}
Basically, the method Throw() tells the ball to check the direction the player is facing and then multiply it by ballForce. Then, it uses the ForceMode2d.Impulse method to apply calculated force to the ball for a second and it works on left or right direction.
Thanks Jkimishere for a nudge in a propper direction!
You might need a variable to check if the player is facing right/left.
If the player is, just add force to the ball depending on the direction.
if(!playerHasABall) {return;}
Instantiate(ball,
ballSpawn.position,
transform.rotation);
//Check which way the player is facing and add forrce to that direction.
//Adding a FacingRight boolean might help.....
playerHasABall = false;
I am in the process of making a game in Unity and I have run into a problem. I created a heart system UI + script and and enemy + script. In my game, I have 3 lives but when I made the enemy attack me, he one hits me. Is there a way that I can have a delay between each attack.
Here are the scripts.
Enemy Script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Enemy : MonoBehaviour
{
public Transform attackPoint;
public float attackrange = 0.5f;
public LayerMask playerlayers;
public float speed = 3f;
private Transform target;
IEnumerator Cooldown()
{
yield return new WaitForSeconds(3);
}
private void Update()
{
if (target != null)
{
float step = speed * Time.deltaTime;
transform.position = Vector2.MoveTowards(transform.position, target.position, step);
Collider2D[] hitplayers = Physics2D.OverlapCircleAll(attackPoint.position, attackrange, playerlayers);
foreach (Collider2D player in hitplayers)
{
player.GetComponent<HeartSystem>().TakeDamage(1);
StartCoroutine(Cooldown());
}
}
}
private void OnTriggerEnter2D(Collider2D other)
{
if (other.gameObject.tag == "Player")
{
target = other.transform;
}
}
private void OnTriggerExit2D(Collider2D other)
{
if (other.gameObject.tag == "Player")
{
target = null;
}
}
void OnDrawGizmosSelected()
{
if (attackPoint == null)
return;
Gizmos.DrawWireSphere(attackPoint.position, attackrange);
}
}
And here is my health system script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class HeartSystem : MonoBehaviour
{
public GameObject[] hearts;
public int life;
void Update()
{
if (life < 1)
{
Destroy(hearts[0].gameObject);
SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex + 1);
}
else if (life < 2)
{
Destroy(hearts[1].gameObject);
}
else if (life < 3)
{
Destroy(hearts[2].gameObject);
}
}
public void TakeDamage(int d)
{
life -= d;
}
}
I hope we can find a solution.
So from what i understood from your code: the enemy targets the player on collision and once the player is targeted it receives damage on update.
The problem may be caused by the fact that the update method runs more than once until the collision ends. That would mean that your cooldown is not working.
I don't understand the way your timer works but I can tell you how i usually do.
Let's say the cooldown is 1sec. After attacking the player the first time you get the current time, add 1 second to it and store it like "nextAttackTime". Next time the enemy tries to attack it will check if the current time is equal or higher to the "nextAttackTime".
Your way of doing the cooldown looks very elegant but if it really isn't working you can consider trying it the way i described. it may not be as elegant but it is reliable.
-----EDIT-----
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Enemy : MonoBehaviour
{
public Transform attackPoint;
public float attackrange = 0.5f;
public LayerMask playerlayers;
public float speed = 3f;
private Transform target;
//First we will need a variable to store the time when the next attack will be possible, it starts with 0. We'll also create a public variable to define the cooldown duration
private float nextAttackTime = 0f;
public float attackCoolDown = 3f;
IEnumerator Cooldown()
{
yield return new WaitForSeconds(3);
}
private void Update()
{
if (target != null)
{
float step = speed * Time.deltaTime;
transform.position = Vector2.MoveTowards(transform.position, target.position, step);
Collider2D[] hitplayers = Physics2D.OverlapCircleAll(attackPoint.position, attackrange, playerlayers);
foreach (Collider2D player in hitplayers)
{
//then before dealing the damage we check if it is already time to attack again
if(Time.time >= nextAttackTime){
player.GetComponent<HeartSystem>().TakeDamage(1);
//After dealing damage we reset the time for the next attack. The Time.time should return the time in seconds that the game has been running and we'll add 3 seconds to that to define the time for the next attack.
nextAttackTime = (Time.time + attackCoolDown);
//StartCoroutine(Cooldown());
}
}
}
}
So this is the editted code with the changes I suggested. I edited it right here in StackOverflow with no help of a code editor so there could be some typos.
I'm using this code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class CollisionPlayer : MonoBehaviour
{
public bool alreadyDied = false;
public GameObject player;
public float timeDeath;
public ParticleSystem particles;
public GameObject explosionGO;
private SpriteRenderer sr;
private BoxCollider2D bc;
private PlayerController walkScript;
void Start()
{
sr = GetComponent<SpriteRenderer>();
bc = GetComponent<BoxCollider2D>();
walkScript = GetComponent<PlayerController>();
}
void OnCollisionEnter2D (Collision2D collide)
{
if (collide.gameObject.CompareTag("Dead"))
{
Instantiate(particles, player.transform.position, Quaternion.identity);
Instantiate(explosionGO, player.transform.position, Quaternion.identity);
CinemachineShake.Instance.ShakeCamera(30f, .1f);
alreadyDied = true;
}
}
void Update()
{
if(alreadyDied == true)
{
timeDeath -= Time.deltaTime;
sr.enabled = false;
bc.enabled = false;
walkScript.enabled = false;
}
if(timeDeath <= 0)
{
SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
}
}
}
This is the bullet's code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class LeftBulletScript : MonoBehaviour
{
// Start is called before the first frame update
public float speed;
public float destructionLeftTime;
public ParticleSystem particles;
private GameObject thisGameObject;
void Start()
{
thisGameObject = this.gameObject;
Destroy(gameObject, destructionLeftTime);
}
void Update()
{
transform.Translate(Vector2.left * speed * Time.deltaTime);
if(destructionLeftTime > 0.05f)
{
destructionLeftTime -= Time.deltaTime;
}
else
{
Instantiate(particles, thisGameObject.transform.position, Quaternion.identity);
}
}
}
This code should spawn some particles and a sound effect when the player gets hit by something with tag "Dead". But that does not happen. I have a box collider 2D on both the bullet (that should kill me) and the player. My Rigidbody2D is dynamic on the player with z freezed. The bullet does not have a rigidbody. I made sure that the bullet actually has the tag "Dead", spelled the exact same way as the way I wrote on the script. The weirdest thing is that I used this code on another game and nothing changed (just the name of a script). Both the player and the bullet are on the same layer. Anyone could tell me what could have happened?
Hello i want to create a group of the same prefab following the player in my game. I already got the prefab intantiation to follow the player but when there is more than one they just follow the exact same path on top of each other. is there a way where they can follow the player but act like a bunch of bees moving?
Thanks!
This is the script on my prefab:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class KillerMovement : MonoBehaviour {
public GameObject player;
void FixedUpdate()
{
Vector2 toTarget = player.transform.position - transform.position;
float speed = 0.5f;
transform.Translate(toTarget * speed * Time.deltaTime);
}
}
The best solution depends on you game logic, but you may consider having a delay before starting following (you can tweak the delay depending on the position you want to the particular object to assume in the trail.
using System.Collections;
using UnityEngine;
public class Follower : MonoBehaviour
{
public GameObject player;
public float delay = 0f;
public float speed = .5f;
bool isReady = false;
void Start()
{
StartFollowing();
}
public void StartFollowing()
{
StartCoroutine(WaitThenFollow(delay));
}
IEnumerator WaitThenFollow(float delay)
{
yield return new WaitForSeconds(delay);
isReady = true;
Debug.Log(gameObject.name);
Debug.Log(Time.time);
}
void FixedUpdate()
{
if (isReady && player != null)
{
Vector2 toTarget = player.transform.position - transform.position;
transform.Translate(toTarget * speed * Time.deltaTime);
}
}
}
I've called StartFollowing in the Start method for you to test the code. You should call this method whenever approrpiate in your game logic.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;
public class AIController : MonoBehaviour {
[Header("Player interaction")]
[SerializeField] private GameObject target;
[SerializeField] private int damage;
[SerializeField] private float attackDelay;
[SerializeField] private float stunTime;
[SerializeField] private int health;
public int Health{
get{return health; }
set{ health = value;
agent.speed = runningSpeed;
agent.SetDestination(target.transform.position);
onPatrol = false;
if (health <= 0){
Destroy(gameObject);
}
}
}
// Update is called once per frame
void Update () {
CanAttack(target);
}
here i want to make sure that the AI will attack the player only when he is in front of the AI and within .5 meters. the reason i use this instead of OnTriggerEnter is that the AI will only end up attacking once and then just stand on top of the player without really doing anything further
void CanAttack (GameObject other)
{
Vector3 vectorToTarget = other.transform.position - transform.position;
float angleToTarget = Vector3.Angle(transform.forward, vectorToTarget);
if (angleToTarget <= FOV)
{
RaycastHit raycastData;
if (Physics.Raycast(transform.position, vectorToTarget, out raycastData, .5f))
{
GameObject newTarget = raycastData.collider.gameObject;
Attack(target);
}
}
}
I have also used Attack(other) and this still does not work
void Attack(GameObject other)
{
if (!hasAttacked)//if the AI has not recently attacked
{
if (!Player.isShieldOn)//if the player shield is not up
{
if (!Player.hasShieldBraclet)//if the player has the shield braclet
{
other.gameObject.GetComponent<Player>().Health -= damage - ShieldBraclet.dmgReduction;//reduce the amount of damage taken
}
else
{
other.gameObject.GetComponent<Player>().Health -= damage;//otherwise take normal damage
}
StartCoroutine("DelayAttack");//delay time until AI can attack again
}
else
{
StartCoroutine(Stun(stunTime));//if the shield was up stun this enemy
}
}
}
this is used to make sure that the AI waits a moment before attacking again that way the player doesn't die instantly upon touching the AI.
IEnumerator DelayAttack()
{
hasAttacked = true;//the AI has attacked
yield return new WaitForSeconds(attackDelay);//wait to attack again
hasAttacked = false;//the AI can now attack again
}
}
For the most part everything runs fine but when it reaches the code to deal damage to the player it tells me that the object reference is not set to an instance of an object. How can I fix this?
The Specific error code is: NullReferenceException: Object reference not set to an instance of an object Enemy.Attack(UnityEngine.GameObject other).
This is referring to the line
other.gameObject.GetComponent<Player>().Health -= damage - ShieldBraclet.dmgReduction;//reduce the amount of damage taken