How to make my powerup last for about five seconds then go back to normal?

Questions & Answers
1

Hey guys, I’ve made a PacMan and I’ve got a powerup that speeds you up. But what I need help with is that I only want it to last about 5 seconds then it returns to normal speed. The game is in 2D if that matters which I doubt it. Here is my script below.

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

public class PacmanMove : MonoBehaviour
{
public float speed = 0.4f;
Vector2 dest = Vector2.zero;
public Text countText;
private int count;
private Rigidbody2D rb;

void Start()
{
    dest = transform.position;
    rb = GetComponent<Rigidbody2D>();
    count = 0;
    SetCountText();

}

void FixedUpdate()
{
    // Move closer to Destination
    Vector2 p = Vector2.MoveTowards(transform.position, dest, speed);
    GetComponent<Rigidbody2D>().MovePosition(p);

    // Check for Input if not moving, this is also all the movement
    if ((Vector2)transform.position == dest)
    {
        if (Input.GetKey(KeyCode.UpArrow) && valid(Vector2.up))
            dest = (Vector2)transform.position + Vector2.up;
        if (Input.GetKey(KeyCode.RightArrow) && valid(Vector2.right))
            dest = (Vector2)transform.position + Vector2.right;
        if (Input.GetKey(KeyCode.DownArrow) && valid(-Vector2.up))
            dest = (Vector2)transform.position - Vector2.up;
        if (Input.GetKey(KeyCode.LeftArrow) && valid(-Vector2.right))
            dest = (Vector2)transform.position - Vector2.right;
    }

    // Animation Parameters
    Vector2 dir = dest - (Vector2)transform.position;
    GetComponent<Animator>().SetFloat("DirX", dir.x);
    GetComponent<Animator>().SetFloat("DirY", dir.y);
}

bool valid(Vector2 dir)
{
    // Cast Line from 'next to Pac-Man' to 'Pac-Man'
    Vector2 pos = transform.position;
    RaycastHit2D hit = Physics2D.Linecast(pos + dir, pos);
    return (hit.collider == GetComponent<Collider2D>());
}

void  OnTriggerEnter2D(Collider2D other)
{
    if (other.gameObject.CompareTag("Pacdot"))
    {
        other.gameObject.SetActive(false);
        count = count + 10;
        SetCountText();
    }

    // if Pacman collides with "PowerUp" his speed becomes that
    if (other.gameObject.CompareTag("PowerUp"))
    {
        speed = 2f;
    }
}

//shows the score that you have from the PacDots
void SetCountText()
{
    countText.text = "Count: " + count.ToString();
}

}

2

Use a coroutine

IEnumerator PowerUp()
    {
        speed = 2f;
        yield return new WaitForSeconds(5f);
        speed = 1f;
        
    }

And Call it OnTriggerEnter() where you have the speed =2f like this:

    if (other.gameObject.CompareTag("PowerUp"))
         {
           StopCoroutine(PowerUp());  
           StartCoroutine(PowerUp());
         }

Now in case you encounter a 2nd PowerUp before the first is finished it will stop the first and initiate a second one. Of course if you don’t want that behaviour and want the PowerUp only to last 5 secs even if you pick one more, while on the effect is on, then you need a bool to determine if you are on a PowerUp or not. Hope that helps.

3

You could use boolean for determining if powerup state is on. or int/string with multiple states for like normal, faster speed, bigger jump… etc…
and check the state with if statement and do the stuff inside it.
You can use simple timer/counterdown while the powerup is on.

int state = 0; // 0 = normal, 1 = faster
public float speedupgrade  = 2f;
public float normalspeed = 1f;
private float speed;
float speedUpgradeLeft = 0;
public float speedUpgradeLenght = 5f; //5 seconds
...

...
if(state == 1) { // or you could use switch-statement if you have many states
    speed = normalspeed + speedupgrade; // 1f + 2f = 3f
} else if (state == 2) {
     // do other stuff
} else {
    speed = normalspeed; // 1f
}

// then just use speed variable
Vector2 p = Vector2.MoveTowards(transform.position, dest, speed);

 // then use timer to change state
 if(speedUpgradeLeft  > 0) {
      speedUpgradeLeft -= Time.deltatime;
 }
 else {
     state = 0;
 }
...

...
//On your powerup trigger:
// then trigger speedupgrade by setting time on it.
speedUpgradeLeft = speedUpgradeLenght;
// or adding more time on it
speedUpgradeLeft += speedUpgradeLenght;
// And change the state accordingly
state = 1;
...
4

I’m soo confused @PizzaPie. I’m not the best coder so I don’t understand the vocabulary that you were using. I know that I have to put it the couritine somewhere but I don’t know when. Would you be clearer or, (i know this isn’t really helping,) could you just do it for me. I mean that in the nicest way possible. I honestly have no idea where to put the script that you gave me.