XR Step-by-Step 2023! Meta Quest: Targets and Explosions! Unity 2022 + Open XR + XR Interaction Toolkit

Virtual and Augmented Reality together are now referred to as XR or “Extended-Reality”.
You’re in the right place at the right time to build something amazing in XR!
XR applications can be created in Unity for many devices, our focus will be on Microsoft Hololens 2 and the Meta Quest

In this blog post series we will focus on Meta Quest!

Check out other blog articles in this (and other) series!
Quick links to Lance’s latest XR Step-by-Step blog articles by device

Our XR experience is looking very professional, but we need things to target… and of course – to blow things up!

Full Step-by-Step Instructions!

Goals…

Tags
Coding
Explosions!

Download the finished code for this blog article @ Github Repo

Tags

Let’s repurpose our original cube into a target!
In Unity we can “tag” different objects so when they collide we can have different reactions. For example, we will tag the cube as a target which we’ll make explode and disappear — where the ground and the table will not…

(Hierarchy) Click Cube
(Inspector) Click the dropdown arrow next to Tag
Click Add Tag

(Tags & Layers) Click the “+” button
Type target
Click Save

(Tags) Should see target tag
(Tags) Add a bullet tag

(Hierarchy) Click Cube
(Inspector) Click Tag dropdown
Click target

(Project) Click Prefabs folder
Click Bullet
(Inspector) Click the Tag dropdown
Click bullet

Coding

We have everything we need tagged, now lets add code looking for collision between objects with those tags.

(Project) Right-Click in Scripts folder
Click Create
Click C# Scripts -> Rename it Target

Look through the comments in the code… Make sure to SAVE after updating the code
- In a nutshell, we’re looking for a collision with an object that is tagged as bullet
- Playing the explosion animation
- Playing the audio
- Destroying both objects

using UnityEngine;

public class Target : MonoBehaviour
{
    public GameObject hitAnimation;
    public AudioClip hitAudio;

    private void OnCollisionEnter(Collision collision)
    {
        //--- When we hit another game object with the matching tag
        if (collision.collider.tag == "bullet")
        {
            //--- Play our animation at the current position
            Instantiate(hitAnimation, transform.position, transform.rotation);

            //--- Play the audio at the current location
            AudioSource.PlayClipAtPoint(hitAudio,
                this.gameObject.transform.position);

            //--- Make the object hitting disappear
            Destroy(gameObject);

            //--- Make the object that was hit disappear
            Destroy(collision.gameObject);
        }
    }
}

Explosions!

We can apply the Target script to anything we want to explode – so let’s do that – and then make a bunch of targets!

(Hierarchy) Click Cube
(Inspector) Click Add Component -> Add Rigidbody

(Inspector) Within Rigidbody -> Uncheck Use Gravity
- We don’t want our targets to come crashing down… 🙂

(Inspector) Shrink our Cube’s dimensions down a bit…

(Project) Click Scripts folder -> Drag Target script onto Cube

Let’s add the explosion animation and sound!

(Project) Drag CFXR Explosion 1 into Hit Animation

(Project) Drag Explosion 1 into Hit Audio

Build and Run!

One last small thing… I want more targets…
Easy, you can just click on Cube – then CTRL-C CTRL-V and drag them to where you want them in the scene — more explosions!