How do I enable a particle system on collision in Unity?

Question

I'm building a game where the earth is hit by a meteorite. I have programmed the meteorite hitting the earth and both shapes have a sphere collider. I have also designed the explosion particles.

However, I don't know how to activate the explosion once the meteorite collides into the earth.

Here's my code:

Earth rotation script

using System.Collections.Generic;
using UnityEngine;

public class orbit : MonoBehaviour
{
    public Transform world;
    public float rotationSpeed=1f;
    // Start is called before the first frame update
    void Start()
    {
        world = GetComponent<Transform>();
        
        
        Debug.Log("this works on the first frame");
    }

    // Update is called once per frame
    void Update()
    {
        //code for rotating the earth
        world.Rotate(new Vector3(0, rotationSpeed, 0), Space.World);
    }
}

Earth object

Please use the correct tags! Note that [`[unityscript]`](https://stackoverflow.com/tags/unityscript/info) is or better **was** a custom JavaScript flavor-like language used in early Unity versions and is **long deprecated** by now. — derHugo, Jun 01 '22 at 09:36

score 0 · Accepted Answer · answered May 19 '22 at 17:53

In order to do that, you have to add Rigid Body on both elements (earth and meteorite) and activate the "Trigger" option, only on one of them. (Earth for example).

Add a new function in this script you added (the snippet of earth rotation).

Add a new variable (the prefab with your particles).

Activate "Play on Awake" on your Particle System and the "Stop action" to Destroy.

public GameObject explosionPrefab;

void OnCollisionEnter(Collision collision)
{
    ContactPoint contact = collision.contacts[0];
    Quaternion rot = Quaternion.FromToRotation(Vector3.up, contact.normal);
    Vector3 pos = contact.point;

    GameObject explosionParticle = Instantiate(explosionPrefab, pos, rot);
}

How do I enable a particle system on collision in Unity?

1 Answers1