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How to call a randomized loot table method again from within itself to prevent duplicates in Unity?

I have a basic loot table with weighted drop rarities. I am trying to make it so that when the game starts, it will re-roll if the item already exists in a duplicated list.
I've created an empty list in shopManagerScript and am adding each instantiated item to that list. Then I would like to check against that list to see if the item exists. If it does, I want to re-roll again. If it doesn't then go ahead and instantiate the item.
This current code is executing endlessly however, and is crashing my game.
public GameObject shopManager;
public ShopManager shopManagerScript;
[System.Serializable]
public class DropItem
{
public string name;
public GameObject item;
public int dropRarity;
}
public List<DropItem> ShopItemPool = new List<DropItem>();
private void Start()
{
shopManager = GameObject.FindGameObjectWithTag("ShopManager");
shopManagerScript = shopManager.GetComponent<ShopManager>();
SpawnItem();
}
void SpawnItem()
{
int itemWeight = 0;
for (int i = 0; i < ShopItemPool.Count; i++)
{
itemWeight += ShopItemPool[i].dropRarity;
}
int randomValue = Random.Range(0, itemWeight);
for (int i = 0; i < ShopItemPool.Count; i++)
{
if (randomValue <= ShopItemPool[i].dropRarity && !shopManagerScript.shopItems.Contains(ShopItemPool[i].item.ToString()))
{
Instantiate(ShopItemPool[i].item, transform.position, Quaternion.identity);
shopManagerScript.shopItems.Add(ShopItemPool[i].item.ToString());
return;
}
else
{
SpawnItem();
}
randomValue -= ShopItemPool[i].dropRarity;
}
}

The problem here is that SpawnItem method calls SpawnItem inside the for, which results in having more running SpawnItem. Then these running SpawnItem call more SpawnItem. The process continues until stack is overflowed and it falls with StackOverflowException.
In order to fix this you can use continue as mentioned before, but be careful with calling SpawnItem, because if the random keeps generating inappropriate values the method can still be called too many times and the error will be the same.
Another way to fix it is to remove recursive call of it and make another method that loops calling SpawnItem. Just make sure that the logic of looping doesn't fully rely on random, otherwise it's still possible to call the method too many times

Unity Question: How Can I Switch From One prefab To Another With GetAxis?

I want to bind the up and down arrow keys to cycle through different sprites upon being pressed. If one end is reached, it would loop back to the first sprite. I've tried using the following code:
public class PhaseChanger : MonoBehaviour
{
// saved for efficiency
[SerializeField]
public GameObject prefabMoon0;
[SerializeField]
public GameObject prefabMoon1;
[SerializeField]
public GameObject prefabMoon2;
[SerializeField]
public GameObject prefabMoon3;
[SerializeField]
public GameObject prefabMoon4;
// needed for new phase
GameObject currentPhase;
bool previousFramePhaseChangeInput = false;
/// <summary>
/// Start is called before the first frame update
/// </summary>
void Start()
{
currentPhase = Instantiate<GameObject>(prefabMoon0);
}
/// <summary>
/// Update is called once per frame
/// </summary>
void Update()
{
// change phase on up arrow or down arrow
if (Input.GetAxis("ChangePhase") > 0)
{
// only change phase on first input frame
if (!previousFramePhaseChangeInput)
{
previousFramePhaseChangeInput = true;
// Save current position and destroy current phase
Destroy(currentPhase);
// instantiate next phase
if (currentPhase = prefabMoon0)
{
currentPhase = Instantiate(prefabMoon1);
}
else if (currentPhase = prefabMoon1)
{
currentPhase = Instantiate(prefabMoon2);
}
else if (currentPhase = prefabMoon2)
{
currentPhase = Instantiate(prefabMoon3);
}
else if (currentPhase = prefabMoon3)
{
currentPhase = Instantiate(prefabMoon4);
else
{
// no phase change input
previousFramePhaseChangeInput = false;
}
}
}
}
When I attach the script to my main camera and run it, I'm able to make a single change with the up arrow, and then nothing else happens on subsequent presses.
I feel like I'm really close to making this work, but I also may being doing the whole thing inefficiently. Help would be much appreciated, thanks!
Also: I know I said sprites in my post and am sharing a script that calls on prefabs. I didn't know how to approach this using just the sprites without making a prefab for each. Is it possible to do this without separate prefabs for each sprite?

Problems
First of all you are using assignments
currentPhase = XY
where you should be using
currentPhase == XY
The reason why it still compiles is the implicit conversion operator for UnityEngine.Object -> bool. Basically your assigning equals writing
currentPhase = XY;
if(currentPhase)
It won't work like this either way because you are using Instantiate to create a new clone of a prefab which will of course have a different reference than the original prefab it was cloned from.
So even if your checks where looking like
if(currentPhase == XY)
they will ever be true.
Solution
Instead of checking for reference equality I would rather store all prefabs/instances in an array
public GameObject[] phases;
and then simply have an int index for this array so you can simply move to the next element from the array by increasing the index.
private int currentPhase;
And you can increase it and make it wrap around using e.g.
currentPhase = (currentPhase + 1) % phases.Length;
so it will always grow from 0 up to phases.Length - 1 and then start over from 0 again.
And then I don't know the exact requirements of your use case but I would suggest to rather not all the time use Instantiate and Destroy but rather have already all the objects as instances under your object and just (de)actívate them!
you could do this like e.g.
public GameObject[] phases;
private int currentPhase;
private void Awake ()
{
Init();
}
private void Update ()
{
if (Input.GetAxis("ChangePhase") > 0)
{
if (!previousFramePhaseChangeInput)
{
previousFramePhaseChangeInput = true;
NextPhase();
}
}
else
{
previousFramePhaseChangeInput = false;
}
}
// Disables all phases except the first one and sets the current index to 0
private void Init()
{
for(var i = 1; i < phases.Length; i++)
{
phases[i].SetActive(false);
}
phases[0].SetActive(true);
currentPhase = 0;
}
// Disables the current phase and enables the next one
// wraps around at the end of the array
public void NextPhase()
{
phases[currentPhase].SetActive(false);
// increase the counter and wrap around at the end of the array
currentPhase = (currentPhase + 1) % phases.Length;
phases[currentPhase].SetActive(true);
}
If you still want to Instantiate the objects because having them already in the scene is no option (for whatever reason) you could do it right before calling Init like e.g.
public GameObject[] phasePrefabs;
private GameObject[] phases;
private void Awake ()
{
var amount = phasePrefabs.Length;
phases = new GameObject [amount];
for(var i = 0; i < amount; i++)
{
phases[i] = Instantiate(phasePrefabs[i]);
}
Init();
}
Though as said I would prefer to already have them right away as this is way less error prone ;)

Unity: Script attached to child object of DontDestroyOnLoad object being called twice

I am trying to populate various objects in Unity based on some triggers and some data. The data that I am using looks something like this Key === O2 Values are ==== { collected, collected, collected, absent}Key === O3 Values are ==== { collected, collected, present } stored in a Dictionary object Dictionary<string, List<string>> textMap. Following script is attached to these objects:
using System;
using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEngine;
public class SensePlayerProximity : MonoBehaviour {
bool disableEntry = false;
bool disableExit = false;
public bool isCollected = false;
//List<Collider2D> triggerList = new List<Collider2D>();
// Use this for initialization
static Dictionary<string, List<string>> textMap = new Dictionary<string, List<string>>
{
{ "O2", new List<string>() { "present", "absent", "absent", "absent" }},
{ "O3",new List<string>() { "absent", "absent", "absent" }}
};
private void OnTriggerEnter2D(Collider2D collision)
{
if (disableEntry || isCollected)
return;
StartCoroutine(disableTriggersForThisCollectible(10));
List<String> values;
foreach (KeyValuePair<string, List<string>> kvp in textMap)
{
values = kvp.Value;
int foundAtIndex = values.IndexOf("absent");
if (foundAtIndex > -1)
{
gameObject.GetComponent<TextMeshProUGUI>().text = kvp.Key;
values[foundAtIndex] = "present";
textMap.Remove(kvp.Key);
textMap.Add(kvp.Key, values);
logTextMap();
return;
}
}
// if nothing is found, then default the text to empty, since nothing left to be collected now
gameObject.GetComponent<TextMeshProUGUI>().text = "";
}
//called when something exits the trigger
private void OnTriggerExit2D(Collider2D collision)
{
if (disableExit || isCollected)
return;
//Debug.Log("Player is leaving me.. :(");
string key = gameObject.GetComponent<TextMeshProUGUI>().text;
StartCoroutine(disableTriggersForThisCollectible(0.1f));
List<string> values = textMap[key];
int index = -1;
if (values != null)
index = values.IndexOf("present");
if(index >= 0)
{
values[index] = "absent";
textMap.Remove(key);
textMap.Add(key, values);
gameObject.GetComponent<TextMeshProUGUI>().text = "";
logTextMap();
}
}
IEnumerator disableEntryTrigger(float t)
{
disableEntry = true;
// disable the trigger collider for t seconds
yield return new WaitForSeconds(t);
disableEntry = false;
}
IEnumerator disableExitTrigger(float t)
{
disableExit = true;
// disable the trigger collider for t seconds
yield return new WaitForSeconds(t);
disableExit = false;
}
void logTextMap()
{
string debugString = "";
foreach (KeyValuePair<string, List<string>> kvp in textMap)
{
debugString += "Key === " + kvp.Key + " Values are ==== { " + String.Join(", ", kvp.Value.ToArray()) + " }";
}
Debug.Log(debugString);
}
}
The script detects trigger collisions with BoxCollider2D attached to my player, and it has "Sensor" tag name attached to it. I disable the triggers for 10s whenever OnTriggerEnter2D event occurs and for 0.1s whenever OnTriggerExit2D event occurs.
I have some fixed textobjects scattered in my level and trying to populate the text in them on the basis of this script above. This script is attached to every such text object.
With the help of these events, I detect if the player is in the vicinity of a text object. If the player is found, then a random key will be populated from the textMap provided that key has at least one value which says "absent". Each key has a list of values, which could be "absent", "present", or "collected". "absent" means that the key is absent from the camera view and thus can be assigned to new collectible text objects. "present" means that the key is present in the current camera view and is not available for the other text objects. "collected" means that the key has already been collected and is not available either. In the example value of textMap which I shown above, for example, there can be 4 copies of the key "O2" in the map, and 3 copies of the key "O3". Out of these, 3 "O2" and 2 "O3" have already been collected. Only 1 copy of "O2" can be assigned to newly triggered text objects and no copy of "O3" is available for them. The script works mostly as expected, except a few time which I am not able to debug. The debug log show that one copy of "O3" is already present in the view, but I went to my scene and could not find "O3" anywhere. I am afraid that this might be happening because all the triggered text objects (to which the above script is attached) are trying to modify the textMap at the same time. I have wasted a lot of time trying to figure this out, but I am just banging my head in the wall. I'd really appreciate if someone could point me in the right direction. My scene with these objects is shown below:
Edit: I found the problem to be DontDestroyOnLoad. The said gameobjest to which SensePlayerProximity script is attached are all children of a DontDestroyOnLoad gameobject called ScenePersist. The problem is happening only when I reload the scene, upon player death. When the scene reloads, new ScenePersist is loaded in the scene, and just before it called the triggerentry method on children before being destroyed. Because of this, OnTriggerEnter2D is called twice, instead of once. How do I fix this problem?
One way to fix this would be to keep all these objects far away from the player spawn point, so that the triggers doesn't occur, but that is not a good way to fix it. Another is to run a coroutine enableTriggers in start method, i.e. disable the triggers by default, but that is not a good solution either.
void Start () {
disableEntry=true;
disableExit = true;
StartCoroutine(enableTriggers());
}
IEnumerator enableTriggers()
{
yield return new WaitForSeconds(0);
disableEntry = false;
disableExit = false;
}
This is how my scene hierarchy looks like:
Here the ScenePersist is set to DontDestroyOnLoad, and it has a lots of sub-child objects (highlighted as collectible) to which the SensePlayerProximity is attached.

The problem is because you disable the trigger, the Enter and Exit methods are not called in pairs. But no code to protect it.
Enter -> present +1, absent -1
Exit -> present -1, absent +1
If the method Enter is called twice, but the method Exit is skipped, now 2 elements in the dictionary become present, but there is only one object (with text O2/O3) in the scene.
Enter -> present +1, absent -1
Left without trigger Exit
Wait 10 seconds
Enter -> present +1, absent -1
Exit -> present -1, absent +1

I solved it by using the OnDestroy method. Before getting destroyed, the object was triggering the OnTriggerEnter2D method. So on getting destroyed I did something similar to what OnTriggerExit2D was doing, as shown below.
void OnDestroy()
{
string key = gameObject.GetComponent<TextMeshProUGUI>().text;
Debug.Log("destroed with key "+ key);
if (!textMap.ContainsKey(key))
return;
List<string> values = textMap[key];
int index = -1;
if (values != null)
index = values.IndexOf("present");
if (index >= 0)
{
values[index] = "absent";
textMap.Remove(key);
textMap.Add(key, values);
gameObject.GetComponent<TextMeshProUGUI>().text = "";
}
}

Objects are null when they should be filled, and the only reason appears to be arbitrary

I'm somewhat new to PUN and Unity so hopefully, I am making some kind of beginner mistake.
void Update(){
if(launch == true){
Debug.Log("launched");
myPhotonView.RPC("ChangeScene", PhotonTargets.All);
}
//myPhotonView.RPC("ChangeScene", PhotonTargets.All);
}
When I run the code above, I can see launched in the console but I get
"NullReferenceException: Object reference not set to an instance of an
object" on this line: myPhotonView.RPC("ChangeScene",
PhotonTargets.All);
When I run it with that line commented out and the line that's outside the if statement uncommented, there is no null reference exception and the method executes. Is there a mistake in the above code, or is this a bug in Photon?
Any help at all is much appreciated. I can post the full code or error messages if anyone thinks it's necessary.
Also, this is less important, but myPhotonView is null in any methods I create that aren't regular MonoBehaviour methods like Start or Update even though I set it as a global variable and filled it in Start before I try to access it. This seems like it might be tied to the other problems I'm having, and it's the only reason I'm using Update for this.
Edit: Here's the entire file:
using UnityEngine;
using System.Collections;
using UnityEngine.SceneManagement;
public class NetworkedPlayer : Photon.MonoBehaviour{
public GameObject avatar;
public PhotonView myPhotonView;
public bool launch = false;
public string destination = "";
//Responsible for avatar movements on the plane
public Transform playerGlobal;
//Responsible for headmovements
public Transform playerLocal;
public Transform playerRotation;
void Start (){
//launch is successfuly set to false
//if(!launch) Debug.LogError("banana");
Debug.Log("Instantiated");
//Necessary for photon voive to work
var temp1 = PhotonVoiceNetwork.Client;
myPhotonView = this.photonView;
//this ensures that only you can control your player
if (photonView.isMine){
Debug.Log("Controlling my avatar");
playerGlobal = GameObject.Find("OVRPlayerController").transform;
playerLocal = playerGlobal.Find("OVRCameraRig/TrackingSpace/CenterEyeAnchor/Pivot");
playerRotation = playerGlobal.Find("OVRCameraRig/TrackingSpace/CenterEyeAnchor");
this.transform.SetParent(playerLocal);
this.transform.localPosition = Vector3.zero;
this.transform.rotation = playerRotation.transform.rotation;
// avatar.SetActive(false);
//Throws null
//GetComponent<PhotonVoiceRecorder> ().enabled = true;
}
}
void OnPhotonSerializeView(PhotonStream stream, PhotonMessageInfo info){
//This sends your data to the other players in the same room
if (stream.isWriting){
stream.SendNext(playerGlobal.position);
stream.SendNext(playerGlobal.rotation);
stream.SendNext(playerLocal.localPosition);
stream.SendNext(playerLocal.localRotation);
}
//This recieves information from other players in the same room
else{
this.transform.position = (Vector3)stream.ReceiveNext();
this.transform.rotation = (Quaternion)stream.ReceiveNext();
avatar.transform.localPosition = (Vector3)stream.ReceiveNext();
avatar.transform.localRotation = (Quaternion)stream.ReceiveNext();
}
}
public void ChangeAndSyncScene(string dest){
Debug.LogError("Dest selected: " + dest);
launch = true;
destination = dest;
Update();
}
void Update(){
if(launch == true){
Debug.LogError("launched");
myPhotonView.RPC("ChangeScene", PhotonTargets.All);
ChangeScene();
}
myPhotonView.RPC("ChangeScene", PhotonTargets.All);
}
[PunRPC]
void ChangeScene(){
Debug.LogError("scene changed");
Application.LoadLevel (destination);
}
}
Edit: I never managed to fix this, but I did get around it. I created gameobjects to give values to other players in the game. PM me for more info

Trying to access instantiated object in 2d array Unity c#. Cant access or change elements?

First time question here.
I'm trying to build a game board like one you would see playing chess. I've made two scripts, one that spawns the board and stores each instantiated tile in a 2d array. And another script that sets the row and column location and onMouseOver prints that location to the console. However this is always print Row = 0 and Col = 0.
I've come to the conclusion that the 2d array is just setting a clone in memory and therefor the stored values I set via calling the function setRC(); are not being being found as the instantiated objects the the Unity scene don't share the memory location.
Anyone have an idea as to how I can fix this?
public class Map : MonoBehaviour {
public static int Row = 7;
public static int Col = 7;
private GameObject[,]boardPiece = new GameObject[Row,Col];
public GameObject prefab;
public GameObject prefab2;
void Start () {
for (int i = 0; i < Row; i++) {
for (int j = 0; j < Col; j++)
{
if(i%2 ==1 && j%2 ==1 || i%2 ==0 && j%2 ==0)
{
boardPiece[i,j] = (GameObject)Instantiate(prefab, new Vector3(i*4.0f,0,j*4.0f),Quaternion.identity);
}else{
boardPiece[i,j] = (GameObject)Instantiate(prefab2, new Vector3(i*4.0f,0,j*4.0f),Quaternion.identity);
}
boardPiece[i,j].GetComponent<BoardPiece>().setRC(i,j);
}
}
}
}
public class BoardPiece : MonoBehaviour {
private int rowPlace;
private int colPlace;
// Use this for initialization
void Start () {
rowPlace = 0;
colPlace = 0;
}
// Update is called once per frame
void Update () {
}
void OnMouseOver(){
string message = "Row: " + rowPlace + " Col: " + colPlace;
print (message);
}
public void setRC(int R, int C)
{
rowPlace = R;
colPlace = C;
print ("set " + rowPlace + "," + colPlace);
}
}

Without a complete code example (difficult or even impractical to provide for Unity3d projects I know, but still...) it is difficult to know for sure what the problem is. However…
While the Start() method is often used in a fashion similar to a constructor, it's important to understand that it's not in fact one. I don't think it's called yet by the time your code is calling the setRC() method on your new object.
This means that the flow of execution is that you first set the row and column values as desired, and then later the BoardPiece.Start() method is called by the Unity3d framework, setting the row and column values back to 0.
Since the rowPlace and colPlace fields are already set to 0 by default when the object is created, I think the best fix is to just remove those two lines from the Start() method altogether. They aren't needed, and I believe they are responsible for the problem you are having.