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unity-game-enginetimerarduino

Using a timer in conjunction with 2 push buttons from arduino


So I am using two push buttons (connected to an Arduino Uno) as an input to my game. The player has to push down both buttons at the same time for the character to move in the game. I want the player to hold down the buttons for a different amount of time in each level. I have a working Arduino and a working Unity timer and player script, but am not able to get the code to do what I want. What I basically want is that only when the player presses the buttons down, does the timer start counting down. Right now, the timer starts as soon as the scene begins. I know that I somehow have to reference the timer script to the button object, I have tried this but it still doesn't work. Note that the timer UI does have a Timer tag on it. I have also referenced the Player Controller script in the Timer script. Right now, Its giving me a range of errors. I have attached an image depicting these errors.error image The Timer script:

    using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.SceneManagement;

public class Timer : MonoBehaviour
{
    //int startTime = 0;
    public bool buttonPressed = false;
    public int timeLeft;
    public Text countdownText;
    GameObject Character;
    void Awake()
    {
        Character = GameObject.FindWithTag("Player");
    }

    public void Start()
    {
        //StartCoroutine("LoseTime");
        BeginTimer();

    }

    void Update()
    {
        countdownText.text = ("Time Left = " + timeLeft);

        if (timeLeft <= 0)
        {
            //StopCoroutine("LoseTime");
            //countdownText.text = "Times Up!";
            Invoke("ChangeLevel", 0.1f);
        }
       }
    public void BeginTimer()
    {
        Character.GetComponent<PlayerController>().Update();

        //gameObject.GetComponent<MyScript2>().MyFunction();
        if (buttonPressed == true )
        {
            StartCoroutine("LoseTime");
        }
        else if (buttonPressed == false)
        {
            StopCoroutine("LoseTime");
        }
    }

IEnumerator LoseTime()
    {
        while (true)
        {
            yield return new WaitForSeconds(1);
            timeLeft--;
        }

    }
    void ChangeLevel()
    {

        SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex + 1);
    }
}

The Player Script:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.IO.Ports;

public class PlayerController : MonoBehaviour
{
    SerialPort sp = new SerialPort("\\\\.\\COM4", 9600);
    //player == GameObject.FindWithTag("Player").GetComponent<>();

    public float Speed;
    public Vector2 height;
    public float xMin, xMax, yMin, yMax;
    public bool buttonPressed = false;
    GameObject Character;

    public void Awake()
    {
        Character = GameObject.FindWithTag("Player");
    }
    public void Start()
    {
        if (!sp.IsOpen)
        { // If the erial port is not open 
            sp.Open(); // Open 
        }
        sp.ReadTimeout = 1; // Timeout for reading
    }

    public void Update()
    {

        if (sp.IsOpen)
        { // Check to see if the serial port is open 
            try
            {

                string value = sp.ReadLine();//To("Button"); //Read the information
                int button = int.Parse(value);
                //float amount = float.Parse(value);
                //transform.Translate(Speed * Time.deltaTime, 0f, 0f);  //walk


                if (button == 0) //*Input.GetKeyDown(KeyCode.Space*/)  //jump
                {
                    buttonPressed = true;

                    Character.GetComponent<Rigidbody2D>().AddForce(height, ForceMode2D.Impulse);

                    Character.GetComponent<Rigidbody2D>().position = new Vector3
                    (
                        Mathf.Clamp(GetComponent<Rigidbody2D>().position.x, xMin, xMax),
                        Mathf.Clamp(GetComponent<Rigidbody2D>().position.y, yMin, yMax)
                    );
                    Timer tmr = GameObject.Find("Timer").GetComponent<Timer>();
                        tmr.BeginTimer();


                }
            }
            catch (System.Exception)
            {


            }
        }
        void ApplicationQuit()
        {
            if (sp != null)
            {

                {
                    sp.Close();
                }
            }
        }
    }
}

I think the problem may be with how I am referencing the scripts in each other.


Solution

  • In your timer you have a quite strange mixup of Update and Coroutine. Also note that BeginTimer is called exactly once! You also shouldn't "manually" call Update of another component.

    I wouldn't use Update at all here. Simply start and stop a Coroutine.

    The Timer script should only do the countdown. It doesn't have to know more:

    public class Timer : MonoBehaviour
    {
        public int timeLeft;
        public Text countdownText;
    
        private bool timerStarted;
    
        public void BeginTimer(int seconds)
        {
            // Here you have to decide whether you want to restart a timer
            timeLeft = seconds;
            // or if you rather want to continue counting down
            //if(!timerStarted) timeLeft = seconds;
    
            StartCoroutine(LoseTime());
        }
    
        public void StopTimer()
        {
            StopAllCoroutines();
        }
    
        private IEnumerator LoseTime()
        {
            timerStarted = true;
    
            while (timeLeft > 0)
            {
                yield return new WaitForSeconds(1);
                timeLeft --;
                countdownText.text = $"Time Left = {timeLeft}";
            }
    
            // Only reached after the timer finished and wasn't interrupted meanwhile
            // Using Invoke here is a very good idea since we don't want to interrupt anymore
            // if the user lets go of the button(s) now
            Invoke(nameof(ChangeLevel), 0.1f);
        }
    
        void ChangeLevel()
        {
            SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex + 1);
        }
    }
    

    In general avoid to use Find at all. If anyhow possible already reference things in the Inspector! If needed you can use Find but only once! What you never want to do is use any of the Find and GetComponent variants repeatedly - rather store the reference the first time and re-use it - and especially not in Update no a per frame basis. They are very expensive calls!

    public class PlayerController : MonoBehaviour
    {
        public float Speed;
        public Vector2 height;
        // I prefer to use Vector2 for such things
        public Vector2 Min;
        public Vector2 Max;
        public bool buttonPressed = false;
    
        // Already reference these via the Inspector if possible!
        public Rigidbody2D Character;
        public Timer timer;
        public Rigidbody2D _rigidbody;
    
        private SerialPort sp = new SerialPort("\\\\.\\COM4", 9600);
    
        private void Awake()
        {
            FetchReferences();
        }
    
        // This is my "secret" tip for you! Go to the component in the Inspector
        // open the ContextMenu and hit FetchReferences
        // This already stores the references in the according fields ;)
        [ContextMenu("FetchReferences")]
        private void FetchReferences()
        {
            if(!Character)Character = GameObject.FindWithTag("Player"). GetComponent<Rigidbody2D>();
            if(!timer) timer = GameObject.Find("Timer").GetComponent<Timer>();
        }
    
        private void Start()
        {
            if (!sp.IsOpen)
            {
                sp.Open(); // Open 
            }
            sp.ReadTimeout = 1;
        }
    
        private void Update()
        {
            // I wouldn't do the serialport open check here
            // your if block simply silently hides the fact that your application
            // doesn't work correctly! Rather throw an error!
            try
            {
                string value = sp.ReadLine(); //Read the information
                int button = int.Parse(value);   
    
                //TODO: Since it isn't clear in your question how you get TWO buttons
                //TODO: You will have to change this condition in order to only fire if both
                //TODO: buttons are currently pressed!
                buttonPressed = button == 0;
                if (buttonPressed)
                {  
                    Character.AddForce(height, ForceMode2D.Impulse);
    
                    // The clamping of a rigidbody should always be done ine FixedUpdate!
                    // Pass in how many seconds as parameter or make the method 
                    // parameterless and configure a fixed duration via the Inspector of the Timer          
                    timer.BeginTimer(3.0f);
                }
                else
                {
                   // Maybe stop the timer if condition is not fulfilled ?
                   timer.StopTimer();
                }
            }
            catch (System.Exception)
            {
                // You should do something here! At least a Log ...
            }
        }
    
        private void FixedUpdate()
        {
            // Here I wasn't sure: Are there actually two different
            // Rigidbody2D involved? I would assume you rather wanted to use the Character rigidbody again!
            Character.position = new Vector3(Mathf.Clamp(Character.position.x, Min.x, Max.x), Mathf.Clamp(Character.position.y, Min.y, Max.y));
        }
    
        // Did you mean OnApplicationQuit here?
        private void ApplicationQuit()
        {
            if (sp != null)
            {
                {
                    sp.Close();
                }
            }
        }
    }
    

    Typed on smartphone but I hope the idea gets clear