transform.localscale not working properly

Unity Engine
1

Right now I’m making a game where a main character can move around in a top down style and shoot arrows at enemies. I don’t want to instansiate arrows because that’s not very efficient, so I made the arrows I need disabled child objects of the player, which I was hoping would mean I could just move the player around and enable and shoot arrows at the correct positions, since the arrow’s transform would be relative to the player, then the arrows would disable to create the illusion that they dissapeared, but when I go to shoot the arrow the second time, the arrow goes back to the original position it had at the start of the scene, rather than a position relative to where the player is, I haven’t worked with child objects in this way before, so I was hoping someone who knew how to do this could help, here’s my script (attached to the arrow object’s)

using UnityEngine;

public class ArrowMovement : MonoBehaviour
{
    public PlayerMovement playerRef;

    private Rigidbody2D rb;

    private void Awake()
    {
        rb = gameObject.GetComponent<Rigidbody2D>();

        gameObject.SetActive(false);
    }

    private void Update()
    {
        rb.AddForce(new Vector2(0, -20));
    }

    private void OnCollisionEnter2D(Collision2D hitInfo)
    {
        playerRef.IsAttacking = false;
        playerRef.animator.SetBool("IsAttacking", false);

        // the arbitrary numbers below is just some offset to make sure the arrow is in the right spot
        transform.position = transform.localPosition + new Vector3(-0.037f, -0.078f, 0);

        gameObject.SetActive(false);
    }
}
2

And yet Instantiate / Destroy makes the code the most straightforward to understand because it models what is happening. Be kind to yourself.

Also, DO NOT OPTIMIZE CODE RANDOMLY… always start by using the profiler:

Window → Analysis → Profiler

If you don’t have a problem, DON’T OPTIMIZE.

https://discussions.unity.com/t/841163/2

If you want to debug your premature optimizations above, you must find a way to get the information you need in order to reason about what the problem is.

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 ← likely this in the collision func
  • the code is executing far MORE OFTEN than you think
  • the code is executing on another GameObject than you think it is

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 put in Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene

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.

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://discussions.unity.com/t/839300/3

3

Thanks for all the advice, I’ll probably be able to get it working with all those tips

4

btw, I got it working, and was able to fix a second bug I found too

1 Like