Ok, so continuing with my game, Im able to instantiate enemies and assign individual sprites to them on startup. When I destroy the enemies, and they all are destroyed when one is hit, I call that same function again. The inspector shows the gameobjects are there, but the sprite renderer component is blank. No error messages are displayed.
Here's my code simplified. This is where my instantiation and rendering method is at:
public class EnemySpawner : MonoBehaviour {
public Sprite[] HiraganaSprites;
public void setEnemies()
{
int counter=0;
while (counter<5)
{
Instantiate (EnemyPrefab, enemyPos, player.transform.rotation);
//label the enemy
EnemyPrefab.tag = "Enemy" + counter;
counter++;
}
//render diff sprites for each
counter=0;
while (counter<5)
{
string en_name="Enemy"+counter;
labelEnemy = GameObject.FindGameObjectWithTag (en_name);
SpriteRenderer renderer=labelEnemy.GetComponent<SpriteRenderer>();
renderer.sprite=Sprites[counter];
counter ++;
}
void Awake()
{
Sprites = Resources.LoadAll<Sprite> ("kana");
}
}
}
I make the call from a different script.
public EnemySpawner enemyspawner;
void function()
{
enemyspawner=gameObject.AddComponent<EnemySpawner>();
enemyspawner.setEnemies();
}
First time around, everything works fine!
Second time, nothing .
Weird thing is the prefabs are there, set on position, just not rendered. Also no error messages.
This is how Im destroying the enemies in case that helps.
while (i<=numenemies)
{
string tag="Enemy"+i;
destroyenemy=GameObject.FindGameObjectWithTag(tag);
Destroy(destroyenemy.gameObject);
i++;
}
You should attach EnemySpawner Script to gameObject and then update the script in which you call setEnemies function as follows -
public EnemySpawner enemyspawner;
void function()
{
enemyspawner=gameObject.GetComponent<EnemySpawner>();
enemyspawner.setEnemies();
}
Related
I am trying to learn how does Unity work and I now struggle with problem that I cannot access script from another script. I was searching on Interner for couple hours, I have tried many options but nothing helped.
I have 2 scripts.
CoinSpawn.cs - attached to Player (I would change it to other object but I dont know yet to which one, because its something that runs in background so it really dont need to be on player)
CollectingCoin.cs - attached to Coin (Coin is object, that its not on game scene on the start, it spawns randomly)
CoinSpawn is script that randomly spawn Instantiate of object Coin. I want to change value of CoinSpawn.currentCoinOnScreen from CollectingCoin. I ve tried
CoinSpawn test = GameObject.Find("CoinSpawn").GetComponent<CoinSpawn>();
and it doesnt work. I also have my both scripts in the same asset folder. What am I doing wrong? Thank you
CoinSpawn.cs
public class CoinSpawn : MonoBehaviour
{
public GameObject coin;
public int maximumCoinPerScreen = 10;
public int currentCoinOnScreen = 0;
private int randomNumber;
private Vector2 spawnPosition;
private void Update()
{
randomNumber = Random.Range(1, 1000);
if(randomNumber >= 0 && randomNumber <= 1 && currentCoinOnScreen != maximumCoinPerScreen)
{
currentCoinOnScreen++;
float spawnY = Random.Range
(Camera.main.ScreenToWorldPoint(new Vector2(0, 0)).y, Camera.main.ScreenToWorldPoint(new Vector2(0, Screen.height)).y);
float spawnX = Random.Range
(Camera.main.ScreenToWorldPoint(new Vector2(0, 0)).x, Camera.main.ScreenToWorldPoint(new Vector2(Screen.width, 0)).x);
spawnPosition = new Vector2(spawnX, spawnY);
GameObject coinObject = Instantiate(coin, spawnPosition, Quaternion.identity);
}
}
}
CollectingCoin.cs
public class CollectingCoin : MonoBehaviour
{
UnityEngine.UI.Text Coins;
public static int totalCoins = 0;
private void Start()
{
Coins = GameObject.Find("Score").GetComponent<UnityEngine.UI.Text>();
}
void OnTriggerEnter2D(Collider2D c2d)
{
if (c2d.CompareTag("Player"))
{
totalCoins++;
Destroy(gameObject);
Coins.text = "COINS: " + totalCoins.ToString();
// TESTING
CoinSpawn test = GameObject.Find("CoinSpawn").GetComponent<CoinSpawn>();
CoinSpawn test2 = GetComponent<CoinSpawn>();
}
}
}
GameObject.Find("CoinSpawn").GetComponent<CoinSpawn>();
Searches for a GameObject with the name CoinSpawn. Since you told us this component is rather attached to the player object it makes sense that it isn't found.
GetComponent<CoinSpawn>();
searches for a CoinSpawn component on the very same object your CollectingCoin is attached to. From your description this clearly also isn't the case.
Since you say the CoinSpawn is attached to the player then you probably rather want to get the component from
void OnTriggerEnter2D(Collider2D c2d)
{
if (c2d.CompareTag("Player"))
{
...
// rather get the component on the player object you collided with
CoinSpawn test = c2d.GetComponent<CoinSpawn>();
}
}
Alternatively assuming there is only one single instance of CoinSpawn in your scene anyway and not necessarily on your player you could use FindObjectOfType
CoinSpawn test = FindObjectOfType<CoinSpawn>();
First of all, Do not ever use GameObject.Find(), its very expensive as it will go through all game objects in your scene to find the object. and this not a performance wise.
There are many ways to do so.
Easyest one:
Add both script to same gameobject as component.
Make a global variable CoinSpawn inside CollectingCoin script and then use [serializedFiled] tag on top of it, by this way, you can drag and drop the reference in the editor before you start play. and you can access it the way you want.
2nd way:
Is same as first one, but instead of serializedFiled, just cache it at the beginning by using GetComponent.
Just make sure you have both scripts attached to the same gameobject.
public class CollectingCoin : MonoBehaviour
{
UnityEngine.UI.Text Coins;
public static int totalCoins = 0;
CoinSpawn coinSpawn;
private void Start()
{
coinSpawn = GetComponent<CoinSpawn>();
Coins = GameObject.Find("Score").GetComponent<UnityEngine.UI.Text>();
}
void OnTriggerEnter2D(Collider2D c2d)
{
if (c2d.CompareTag("Player"))
{
totalCoins++;
Destroy(gameObject);
Coins.text = "COINS: " + totalCoins.ToString();
// DO Whaterver you want with coinSpawn here
}
}
}
I'm making a game on unity where the user selects a character and the character spawns into the game world. The world consists of different doors. I want to add a transition animation (just a regular fade) between scenes in the game world but because the character is instantiated during runtime, I'm not sure how to attach the animator to the character. I also want the animation to trigger upon collision of the player with a door. I know how to create the animation clips and the animator but I need help on knowing when and how to attach the animator to an object that's going to be instantiated during runtime.
Will I attach the animator in OnCollisionEnter() function? If so, how do I reference that animator through code?
Here is my code for OnCollisionEnter in a script that is attached to the player during runtime. (this works fine)
private void OnCollisionEnter(Collision collision)
{
GameObject door = collision.gameObject;
if (door.CompareTag("ExitDoor"))
SceneManager.LoadScene(0); // spawn back at main lobby
else if (door.CompareTag("RoomDoor"))
{
GameObject Room = door.transform.parent.gameObject;
if (Room.name.Equals("Room1Door"))
SceneManager.LoadScene(1); // go to first room
if (Room.name.Equals("Room2Door"))
SceneManager.LoadScene(2); // go to second room
if (Room.name.Equals("Room3Door"))
SceneManager.LoadScene(3); // go to third room
}
}
And here is the script of instantiating the player during runtime when the scene is loaded (this is in another script)
public GameObject InstantiatePlayer()
{
characterIndex = PlayerPrefs.GetInt(playerprefkey);
selectedChar = characters[characterIndex];
selectedChar.tag = "Player";
selectedChar.AddComponent<MoveRooms>(); //attaches the script where OnCollisionEnter is
return Instantiate(selectedChar, spawnPoint.transform.position, spawnPoint.transform.rotation);
}
to get the Animator , you can do this if the script is attached
Animator anim;
void Start()
{
anim = gameObject.GetComponent<Animator>();
}
else if it is not attached you can try something like this
GameObject object;
Animator anim;
void Start()
{
object = GameObject.Find("objectsname");
anim = object.GetComponent<Animator>();
}
For further details how to use Animator
https://docs.unity3d.com/ScriptReference/Animator.html
https://docs.unity3d.com/ScriptReference/Animator.Play.html
https://docs.unity3d.com/ScriptReference/Animator.SetTrigger.html
As for a transition, you can try to use Caroutines. What Caroutines are is it executes a piece of code 'on the side' whie the other codes continue. It can be used to "wait" for a few seconds (or more). Its very useful and you can do alot with it.
some examplee
public class ExampleClass : MonoBehaviour
{
void Start()
{
// Start function as a coroutine.
StartCoroutine(waitForSeconds);
}
private IEnumerator waitForSeconds()
{
//do something
yield return new WaitForSeconds(1f); // the number is in seconds.
//do something else
}
}
https://docs.unity3d.com/ScriptReference/Coroutine.html
New to unity.
So I created a simple a simple muzzle flash particle animation that is supposed to be displayed on enemies gun when the player gets close to him, simulating a shot without the actual bullet. However I get a null reference exception in this part muzzleFlash.Play(); I believe it's because I am not actually getting the muzzle flash component in the start function with the code I have, actually I know that is it after going to in to debug mode I found out. I am having a really hard time figuring out how to access that component. Below is my code and I'm also posting a picture of my hierarchy. Thanks in advance.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class StaticShootingEnemy : MonoBehaviour
{
[SerializeField] private float _range = 12f;
private Transform _player;
private bool _alive;
private float _distance;
private ParticleSystem muzzleFlash;
// Use this for initialization
void Start()
{
_player = GameObject.Find("Player").transform;
_alive = true;
muzzleFlash = (ParticleSystem)this.gameObject.GetComponent("muzzleFLash");
}
// Update is called once per frame
void Update()
{
_distance = Vector3.Distance(this.transform.position, _player.transform.position);
if (_alive && _distance < _range)
AttackPlayer();
}
private void AttackPlayer()
{
//Turning enemy to look at player
transform.LookAt(_player);
Ray ray = new Ray(transform.position, transform.forward);
RaycastHit hit;
if (Physics.SphereCast(ray, 0.75f, out hit))
{
//TODO: Fix enemy shooting fast when gettting close to him.
GameObject hitObject = hit.transform.gameObject;
if (hitObject.GetComponent<PlayerController>())
{
muzzleFlash.Play();
Debug.Log("Player Hit!");
}
else
muzzleFlash.Stop();
}
}
public void SetAlive(bool alive)
{
_alive = alive;
}
}
You probably have an object "muzzleFlash" as child to object your script attached to. So, in this case you'd better have a reference to your ParticleSystem object that is called muzzleFlash.
[SerializeField] private ParticleSystem muzzleFlash; // drag and drop your ParticleSystem muzzleFlash in inspector
or at least you could find that muzzleFlash like this
GameObject muzzleFlashObj = GameObject.Find("muzzleFlash");
ParticleSystem muzzleFlash = muzzleFlashObj.GetComponent<ParticleSystem>();
In your case it's null because there is probably no component that is called MuzzleFlash on that object. The component you want to get is ParticleSystem.
What component is the staticshootingenemy script on? if it is not on the same component as the particle system then its not finding it because this.gameObject.GetComponent("muzzleFLash") does not exist on that component. You can use GameObject.Find("muzzleFLash") to search for the particle system.
So back to your comment, you could implement something like a pool for your muzzle flashes.
public class MuzzleFlashEffect : MonoBehaviour
{
[SerializeField] private ParticleSystem particleEffect;
private Queue<MuzzleFlashEffect> poolQueue;
public void SetPoolQueue(Queue<MuzzleFlashEffect> queue)
{
poolQueue = queue;
}
public void Play()
{
StartCoroutine(Playing());
}
private IEnumerator Playing()
{
particleEffect.Play();
while (particleEffect.isPlaying)
{
yield return null; // wait until particle animation is done, then recycle effect
}
particleEffect.Stop();
poolQueue.Enqueue(this); // recycle this effect
}
// you can do the same thing for Animation as well, or even write some abstract PoolableVFX class that would be usefull for Animation , ParticleSystems etc..
}
//assume you have some game controller that manage what is going on in the scene
public class GameController : MonoBehaviour
{
[SerializeField] private MuzzleFlashEffect muzzleFlashPrefab;
private Queue<MuzzleFlashEffect> poolQueue = new Queue<MuzzleFlashEffect>(10); // 10 is enough i guess and it's good to set it at instantiation to avoid memory fragmentation
private MuzzleFlashEffect GetMuzzleFlash(Vector3 pos, Quaternion rot)
{
MuzzleFlashEffect muzzleFlash;
// if we already have some effects, then play them, otherwise make a new one and recycle it then
if (poolQueue.Count > 0)
{
muzzleFlash = poolQueue.Dequeue();
}
else
{
muzzleFlash = Instantiate(muzzleFlashPrefab);
muzzleFlash.SetPoolQueue(poolQueue);
}
muzzleFlash.transform.position = pos;
muzzleFlash.transform.rotation = rot;
return muzzleFlash;
}
void Update()
{
// your fancy logic ...
GameObject mutantGunEnd = new GameObject("mutant");
//assume that here you want your muzzle flash effect, so you do:
var muzzleFlash = GetMuzzleFlash(mutantGunEnd.transform.position, mutantGunEnd.transform.rotation); // or you might want to pass mutantGunEnd.transform.forward instead, it depends...
muzzleFlash.Play();
// your fancy logic ...
}
}
So, in this case you have only as many instance of ParticleEffect as you need and saving some resources. You could also create a universal generic pool for any type of object you want to recycle. (you want to recycle instead of instantiation, cuz Instantiation is cpu expensive).
M.b this is a bit overkill here, but i just wanted to share how would i think about this here
I've searched around and I just can't get this to work. I think I just don't know the proper syntax, or just doesn't quite grasp the context.
I have a BombDrop script that holds a public int. I got this to work with public static, but Someone said that that is a really bad programming habit and that I should learn encapsulation. Here is what I wrote:
BombDrop script:
<!-- language: c# -->
public class BombDrop : MonoBehaviour {
public GameObject BombPrefab;
//Bombs that the player can drop
public int maxBombs = 1;
// Update is called once per frame
void Update () {
if (Input.GetKeyDown(KeyCode.Space)){
if(maxBombs > 0){
DropBomb();
//telling in console current bombs
Debug.Log("maxBombs = " + maxBombs);
}
}
}
void DropBomb(){
// remove one bomb from the current maxBombs
maxBombs -= 1;
// spawn bomb prefab
Vector2 pos = transform.position;
pos.x = Mathf.Round(pos.x);
pos.y = Mathf.Round(pos.y);
Instantiate(BombPrefab, pos, Quaternion.identity);
}
}
So I want the Bomb script that's attached to the prefabgameobject Bombprefab to access the maxBombs integer in BombDrop, so that when the bomb is destroyed it adds + one to maxBombs in BombDrop.
And this is the Bomb script that needs the reference.
public class Bomb : MonoBehaviour {
// Time after which the bomb explodes
float time = 3.0f;
// Explosion Prefab
public GameObject explosion;
BoxCollider2D collider;
private BombDrop BombDropScript;
void Awake (){
BombDropScript = GetComponent<BombDrop> ();
}
void Start () {
collider = gameObject.GetComponent<BoxCollider2D> ();
// Call the Explode function after a few seconds
Invoke("Explode", time);
}
void OnTriggerExit2D(Collider2D other){
collider.isTrigger = false;
}
void Explode() {
// Remove Bomb from game
Destroy(gameObject);
// When bomb is destroyed add 1 to the max
// number of bombs you can drop simultaneously .
BombDropScript.maxBombs += 1;
// Spawn Explosion
Instantiate(explosion,
transform.position,
Quaternion.identity);
In the documentation it says that it should be something like
BombDropScript = otherGameObject.GetComponent<BombDrop>();
But that doesn't work. Maybe I just don't understand the syntax here. Is it suppose to say otherGameObject? Cause that doesn't do anything. I still get the error : "Object reference not set do an instance of an object" on my BombDropScript.maxBombs down in the explode()
You need to find the GameObject that contains the script Component that you plan to get a reference to. Make sure the GameObject is already in the scene, or Find will return null.
GameObject g = GameObject.Find("GameObject Name");
Then you can grab the script:
BombDrop bScript = g.GetComponent<BombDrop>();
Then you can access the variables and functions of the Script.
bScript.foo();
I just realized that I answered a very similar question the other day, check here:
Don't know how to get enemy's health
I'll expand a bit on your question since I already answered it.
What your code is doing is saying "Look within my GameObject for a BombDropScript, most of the time the script won't be attached to the same GameObject.
Also use a setter and getter for maxBombs.
public class BombDrop : MonoBehaviour
{
public void setMaxBombs(int amount)
{
maxBombs += amount;
}
public int getMaxBombs()
{
return maxBombs;
}
}
use it in start instead of awake and dont use Destroy(gameObject); you are destroying your game Object then you want something from it
void Start () {
BombDropScript =gameObject.GetComponent<BombDrop> ();
collider = gameObject.GetComponent<BoxCollider2D> ();
// Call the Explode function after a few seconds
Invoke("Explode", time);
}
void Explode() {
//..
//..
//at last
Destroy(gameObject);
}
if you want to access a script in another gameObject you should assign the game object via inspector and access it like that
public gameObject another;
void Start () {
BombDropScript =another.GetComponent<BombDrop> ();
}
Can Use this :
entBombDropScript.maxBombs += 1;
Before :
Destroy(gameObject);
I just want to say that you can increase the maxBombs value before Destroying the game object. it is necessary because, if you destroy game object first and then increases the value so at that time the reference of your script BombDropScript will be gone and you can not modify the value's in it.
I'm having a bit of trouble getting the Vector3 wayPointPosition to my other script called Walking and changing it into the Transform target. My troubles lie in the fact that I'm trying to grab this dynamic variable from WayPointPositioner (it changes depending on what object is clicked in the stage and whether the player overlaps with this waypoint) and import and use it in another script.
Below is the code I'm using.
WayPointPositioner
using UnityEngine;
using System.Collections;
public class WayPointPositioner : MonoBehaviour {
public Vector3 wayPointPosition = Vector3.zero;
private bool checkPlayerWaypointCollision;
void Start()
{
}
void OnTriggerStay2D (Collider2D other)
{
// Check if collision is occuring with player character.
if (other.gameObject.name == "Player")
{
checkPlayerWaypointCollision = true;
}
else
{
checkPlayerWaypointCollision = false;
}
}
//Check if object is clicked
void OnMouseDown ()
{
// If its the player, then return a new position for the player to move to for walking
// Else debug that its not so
if (checkPlayerWaypointCollision == false)
{
Debug.Log ("Object not colliding and retrieving position");
Debug.Log (wayPointPosition);
Debug.Log (gameObject.name);
wayPointPosition = new Vector3 (transform.position.x, transform.position.y, 10);
wayPointPosition = Camera.main.ScreenToWorldPoint(wayPointPosition);
}
else
{
Debug.Log ("Object is colliding, no movement needed");
}
}
}
Walking
using UnityEngine;
using System.Collections;
public class Walking : MonoBehaviour {
public Transform target;
public WayPointPositioner wayPointPosition;
public bool walkingAnimation = false;
private Animator anim;
void Awake ()
{
anim = GetComponent<Animator> ();
wayPointPosition = GameObject.FindGameObjectWithTag ("Waypoint").GetComponent<WayPointPositioner> ();
}
void Start ()
{
}
void Update ()
{
Debug.Log ("This is in Walking, WPP =" + wayPointPosition);
}
}
As you can see I'm trying to import the wayPointPosition from the seperate class which is attached to the gameobjects called "Waypoint" (In my current layout those are empty objects with circle colliders to check if they have been clicked). However when I run this, I am not getting my Vector, but I'm getting the name of the last waypoint in the hierarchy (I have currently 6 waypoints which can be clicked) and not a Vector.
I hope someone is able to help me / point out my mistake. I'm still learning C# so I might've made a strange / odd assumption which isn't working.
Kind regards,
Veraduxxz.
It looks like invoking GameObject.FindGameObjectWithTag("Waypoint").GetComponent<WayPointPositioner>(); retrieves a component from the game object which matches the specified tag, as well as a type argument T which derives from MonoBehavior.
Calling this should actually give you an instance of your WayPointPositioner class, which you can then pass to whichever methods you want, and interact with its Vector3 however you would like.