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Question 2d Instantiate Spawner Problem

Discussion in 'Scripting' started by junior333istall, Jan 16, 2023.

  1. junior333istall

    junior333istall

    Joined:
    Jan 11, 2023
    Posts:
    101
    Im pretty new to Unity, but im try to create a spawner where every 2 seconds it will create a circle. Ive watched through the tutorial and when i tested it, it worked! except not how i expected to. It doesnt create a cricle every 2 seconds but every frame. Ive added deltaTime but it doesnt seem to work any idea on how to fix?

    Code (CSharp):
    1. using System.Collections;
    2. using System.Collections.Generic;
    3. using UnityEngine;
    4.  
    5. public class SpawnEnemy : MonoBehaviour
    6. {
    7.     public GameObject enemy;
    8.     public float spawnRate;
    9.     public float time;
    10.     r
    11.     // Start is called before the first frame update
    12.     void Start()
    13.     {
    14.         SpawnEnemys();
    15.     }
    16.  
    17.     // Update is called once per frame
    18.     void Update()
    19.     {
    20.         if(time < spawnRate)
    21.         {
    22.             time = time + Time.deltaTime;
    23.         }
    24.         else
    25.         {
    26.             SpawnEnemys();
    27.             time = 0;
    28.         }
    29.     }
    30.  
    31.     void SpawnEnemys()
    32.     {
    33.         Instantiate(enemy, transform.position, transform.rotation);
    34.     }
    35. }
    36.  
     
  2. Kurt-Dekker

    Kurt-Dekker

    Joined:
    Mar 16, 2013
    Posts:
    39,571
    Make sure you don't put one of these on each thing you spawn!

    Also, what's going on with line 10 above? IS this code even compiling?
     
  3. junior333istall

    junior333istall

    Joined:
    Jan 11, 2023
    Posts:
    101
    oh, yes sorry mustve misclicked when i was writing the question. and yes it is compiling its giving no errors.
     
  4. Kurt-Dekker

    Kurt-Dekker

    Joined:
    Mar 16, 2013
    Posts:
    39,571
    Well to me it certainly LOOKS like it should work, and it's super-super-simple, so that's good.

    You could make it even simpler:

    Code (csharp):
    1. time += Time.deltaTime;
    2. if (time > spawnRate)
    3. {
    4.  SpawnStuff();
    5.  time = 0;
    6. }
    And if it still doesn't work, it's time to debug.

    You must find a way to get the information you need in order to reason about what the problem is.

    Once you understand what the problem is, you may begin to reason about a solution to the problem.

    What is often happening in these cases is one of the following:

    - the code you think is executing is not actually executing at all
    - the code is executing far EARLIER or LATER than you think
    - the code is executing far LESS OFTEN than you think
    - the code is executing far MORE OFTEN than you think
    - the code is executing on another GameObject than you think it is
    - you're getting an error or warning and you haven't noticed it in the console window

    To help gain more insight into your problem, I recommend liberally sprinkling
    Debug.Log()
    statements through your code to display information in realtime.

    Doing this should help you answer these types of questions:

    - is this code even running? which parts are running? how often does it run? what order does it run in?
    - what are the values of the variables involved? Are they initialized? Are the values reasonable?
    - are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

    Knowing this information will help you reason about the behavior you are seeing.

    You can also supply a second argument to Debug.Log() and when you click the message, it will highlight the object in scene, such as
    Debug.Log("Problem!",this);


    If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

    You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

    You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

    You could also just display various important quantities in UI Text elements to watch them change as you play the game.

    If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer or iOS: https://forum.unity.com/threads/how-to-capturing-device-logs-on-ios.529920/ or this answer for Android: https://forum.unity.com/threads/how-to-capturing-device-logs-on-android.528680/

    If you are working in VR, it might be useful to make your on onscreen log output, or integrate one from the asset store, so you can see what is happening as you operate your software.

    Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

    Here's an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

    https://forum.unity.com/threads/coroutine-missing-hint-and-error.1103197/#post-7100494

    When in doubt, print it out!(tm)

    Note: the
    print()
    function is an alias for Debug.Log() provided by the MonoBehaviour class.
     
  5. junior333istall

    junior333istall

    Joined:
    Jan 11, 2023
    Posts:
    101
    upload_2023-1-15_23-8-56.png


    ye this is whats happeneing. also i did make sure to set my public variables. i set the time to 0 and spawnRate to 2