Recursive call to buff/unbuff? C# Unity3D

Question

My goal is to make a single collision detection that will decrease the movement speed of the object it collided with for a specific duration.

What I tried so far:

//Class that detects the collision
if (other.gameObject.tag == "enemy") 
{
    EnemyMovement enemyMove = other.GetComponent <EnemyMovement> ();
    if (enemyMove.slowMove != 1) {
        return;
    }

    enemyMove.Slow (2, 0.5f, true);

    //....

//Class that handles the Enemy-Movement
//The slowfactor gets multiplied with the Vector3 that handles the movementspeed of the Character

void FixedUpdate () 
{
    Movement();
}

void Movement()
{
    gegnerRigid.MovePosition (transform.position + (gegnerMove * slowMove));
}


public void Slow (float duration, float slowFactor, bool slowed)
{
    if (slowed) 
    {
        if (duration > 0) {
            duration -= Time.deltaTime;
            slowMove = slowFactor;
            Slow (duration, slowFactor, slowed);  //this recursive Call leads to huge performance issues, but how to keep the function going?
        } else {
            slowMove = 1;
            slowed = false;
        }
    }
}

So what I wanted to happen: Call the Slow-function if collision happens and make it invoke itself until the duration is 0.

this is incredibly wrong. you just use **Invoke** for timers in Unity3D — Fattie, Dec 01 '16 at 13:46
**never** use recursion, for any reason - ever - in programming. — Fattie, Dec 01 '16 at 13:46
Alright, ty, but how can i keep the function going then? I dont want to use InvokeRepeat cause it cant be used on functions that have parameters — Csharpest, Dec 01 '16 at 13:51
no need for parameters. note that you have the buff/unbuff ON THE OTHER OBJECT. just CALL TO IT from your "boss" object. Good luck — Fattie, Dec 01 '16 at 13:55

score 4 · Accepted Answer · edited Jun 20 '20 at 09:12

Note, the key here is that

1. You have the buff/unbuff on the other object.

You just call to the other object from the 'boss' object. Do not put the actual buff/unbuff code in your 'boss' object. Just "call for a buff".

In other words: always have buff/unbuff code on the thing itself which you are buffing/unbuffing.

2. For timers in Unity just use "Invoke" or "invokeRepeating".

It's really that simple.

A buff/unbuff is this simple:

OnCollision()
  {
  other.GetComponent<SlowDown>().SlowForFiveSeconds();
  }

on the object you want to slow...

SlowDown()
  {
  void SlowForFiveSeconds()
    {
    speed = slow speed;
    Invoke("NormalSpeed", 5f);
    }
  void NormalSpeed()
    {
    speed = normal speed;
    }
  }

If you want to "slowly slow it" - don't. It's impossible to notice that in a video game.

In theory if you truly want to "slowly slow it"...

SlowDown()
  {
  void SlowlySlowForFiveSeconds()
    {
    InvokeRepeating("SlowSteps", 0f, .5f);
    Invoke("NormalSpeed", 5f);
    }
  void SlowSteps()
    {
    speed = speed * .9f;
    }
  void NormalSpeed()
    {
    CancelInvoke("SlowSteps");
    speed = normal speed;
    }
  }

It's that simple.

Omg you just made me very happy, i love you! This showed me a very simple way to fix my problem! thanks alot — Csharpest, Dec 01 '16 at 13:53

Recursive call to buff/unbuff? C# Unity3D

1 Answers1

1. You have the buff/unbuff on the other object.

2. For timers in Unity just use "Invoke" or "invokeRepeating".

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