Challenge - 5 Problems

🎖️

Unity Collision Master

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❓ Predict Output

intermediate

2:00remaining

What is the output when a collision occurs?

Consider this Unity C# script attached to a GameObject with a Rigidbody2D and Collider2D (not set as trigger). What will be printed when this object collides with another object?

Unity

using UnityEngine;

public class CollisionTest : MonoBehaviour
{
    void OnCollisionEnter2D(Collision2D collision)
    {
        Debug.Log($"Collided with {collision.gameObject.name}");
    }

    void OnTriggerEnter2D(Collider2D other)
    {
        Debug.Log($"Triggered by {other.gameObject.name}");
    }
}

ACollided with Enemy

BTriggered by Enemy

CNo output

DBoth 'Collided with Enemy' and 'Triggered by Enemy'

Attempts:

2 left

❓ Predict Output

intermediate

2:00remaining

What happens when a trigger collider is entered?

Given this script on a GameObject with a Collider2D set as trigger and a Rigidbody2D, what will be printed when another GameObject enters its trigger area?

Unity

using UnityEngine;

public class TriggerTest : MonoBehaviour
{
    void OnCollisionEnter2D(Collision2D collision)
    {
        Debug.Log("Collision detected");
    }

    void OnTriggerEnter2D(Collider2D other)
    {
        Debug.Log($"Entered trigger by {other.gameObject.name}");
    }
}

AEntered trigger by Player

BNo output

CCollision detected

DBoth 'Collision detected' and 'Entered trigger by Player'

Attempts:

2 left

🔧 Debug

advanced

2:00remaining

Why does OnTriggerEnter2D not get called?

A developer wrote this script but OnTriggerEnter2D never runs when expected. What is the most likely reason?

Unity

using UnityEngine;

public class TriggerDebug : MonoBehaviour
{
    void OnTriggerEnter2D(Collider2D other)
    {
        Debug.Log("Trigger entered");
    }
}

AThe script is missing Start() method

BThe collider on this GameObject is not set as trigger

CThe Rigidbody2D is missing on this GameObject

DThe method name is incorrect, it should be OnTriggerEnter

Attempts:

2 left

🧠 Conceptual

advanced

2:00remaining

Which statement about OnCollisionEnter2D and OnTriggerEnter2D is true?

Choose the correct statement about how Unity calls OnCollisionEnter2D and OnTriggerEnter2D methods.

AOnTriggerEnter2D requires both colliders to have Rigidbody2D components

BOnCollisionEnter2D is called only if both colliders are triggers

COnCollisionEnter2D is called when a collider marked as trigger is entered

DOnTriggerEnter2D is called when a collider marked as trigger is entered by another collider with Rigidbody2D

Attempts:

2 left

❓ Predict Output

expert

2:00remaining

What is the output of this script when two objects collide and one has a trigger collider?

Analyze the following script attached to a GameObject with a Rigidbody2D and a Collider2D set as trigger. Another GameObject with Rigidbody2D and a normal collider collides with it. What will be printed?

Unity

using UnityEngine;

public class MixedCollision : MonoBehaviour
{
    void OnCollisionEnter2D(Collision2D collision)
    {
        Debug.Log("Collision detected");
    }

    void OnTriggerEnter2D(Collider2D other)
    {
        Debug.Log("Trigger detected");
    }
}

ABoth 'Collision detected' and 'Trigger detected'

BCollision detected

CTrigger detected

DNo output

Attempts:

2 left