How do I Instantiate something and make the created object follow the creator?

Unity Engine
1

Hi I’d like to have a situation like this:

On the player’s Start, the player creates a force field.

On the player’s Update the force field is moved to the player’s position.

2

You could parent the forcefield to the player, that way you don’t need to worry about updating its position.

3

Yes I could, but how do I do it the way I described in the opening post?

4 
public Transform thingToFollow;

void LateUpdate()
{
  transform.position = thingToFollow.position;
}

Another way to accomplish this is by using joints.

This is the path to the dark side, but there is also Unity’s Script Execution Order settings.

5

Here’s another way. Closer to what you wanted.

public class Player : MonoBehaviour
{
  public ForceField forceFieldPrefab;

  void Start()
  {
    forceField = Instantiate(forceFieldPrefab, transform.position, transform.rotation) as ForceField;
  }

  void Update()
  {
    // Do stuff to make the player move.
    // Now update the force field position
    forceField.GoTo(transform.position);
  }

  ForceField forceField { get; set; }
}

public class ForceField : MonoBehaviour
{
  public GoTo(Vector3 worldPosition)
  {
    transform.position = worldPosition;
  }
}
6

The suggested way. This way you can have your force field as a prefab (much desired) and the force field will always be in the right position. BONUS: It will even rotate and scale with the player!!!

public class Player : MonoBehaviour
{
  public ForceField forceFieldPrefab;

  void Start()
  {
    forceField = Instantiate(forceFieldPrefab, transform.position, transform.rotation) as ForceField;
    // Attach forceField as a child.
    forceField.transform.parent = transform;
  }

  ForceField forceField { get; set; }
}
7

It sounds really good. But when I try it I get an error on the on player.start:
Object referenced not set to an instance of an object.

8

Let’s try this. When you put this script on a GameObject, and then select that GameObject, you should see a slot in the Unity Inspector called Force Field Prefab. You need to drag your prefab into that slot.

using UnityEngine;

public class Player : MonoBehaviour
{
  // Drag your force field prefab into the inspector here.
  public GameObject forceFieldPrefab;

  void Start()
  {
    GameObject forceField = Instantiate(forceFieldPrefab, transform.position, transform.rotation) as GameObject;
    if (forceField == null)
      Debug.LogWarning("No prefab to instantiate! Assign in the Inspector.");
    else
      forceField.transform.parent = transform;
  }
}
9

Thanks for being patient with me! And thanks for actually giving me code to work with. Many times I get on this forum people just tell me to make my own code. But I can’t learn that way, I only learn from dissenting things that I can test that work.

I managed to shorten down your code to get the same effect to:

GameObject MyMod= Instantiate(glob.OB_CHSAK,transform.position,transform.rotation) as GameObject;
    MyMod.transform.parent = transform;

Where glob.OB_CHSAK is the force field object stated as:

public static GameObject OB_CHSAK=(GameObject)Resources.Load("Mod/chSak");

In a script that I have that gets called by no object but has a lot of public variables.

1 Like
10

Exactly what @Beennn1 was suggesting. :wink:

1 Like