Recap: Laser Tripwire

Part of the Physics and Gameplay section of Coddy's Unity journey. Lesson 39 of 63.

Challenge

Medium

Guard the vault with a laser tripwire. The Tripwire script sits on the Emitter post, and the Inspector gives it intruders (a LayerMask with the Player layer ticked), the lamp (a Renderer) and a range of 6.

The beam is a ray from the Emitter along its own forward, range units long, that sees only the intruders layers. The Receiver post and the crates are on other layers.
While something blocks the beam, the lamp is red (Color.red); while the beam is clear, it is green (Color.green).
Each time the beam goes from clear to blocked, log Alarm: Player, with the name of what blocked it. Standing in the beam does not log again; leaving and coming back does.

Press Play and walk the player through the beam with the arrows, then Check.

Try it yourself

using UnityEngine;

public class Tripwire : MonoBehaviour
{
    public LayerMask intruders;
    public Renderer lamp;
    public float range = 6f;

    void Update()
    {
    }
}