Visualize rays in Unity using LineRenderers

RayViz.cs

using System.Collections;
using UnityEngine;

// @kurtdekker
//
// Simple way to throw visible rays into a scene using LineRenderers
//
// Useful for debugging raycasts.
//
// May be helpful to call Debug.Break() simultaneously
// so that you can investigate the scene and see what happened.

public class RayViz : MonoBehaviour
{
	const float DefaultLineWidth = 0.25f;
	const float DefaultLifeTime = 2.00f;
	const float DefaultRayLength = 2.00f;

	float lifeTime;

	// For when you have two endpoints in space
	public static RayViz Create(
		Vector3 startPoint,
		Vector3 endPoint,
		float lineWidth = DefaultLineWidth,
		float lifeTime = DefaultLifeTime)
	{
		var rayviz = new GameObject("RayViz.Create()").AddComponent<RayViz>();

		rayviz.lifeTime = lifeTime;

		var LR = rayviz.gameObject.AddComponent<LineRenderer>();
		LR.useWorldSpace = true;

		LR.startWidth = lineWidth;
		LR.endWidth = lineWidth;

		LR.SetPositions(new Vector3[] {
			startPoint,
			endPoint,
		});

		// TODO: you might want to mark this DontDestroyOnLoad() if you
		// need it to survive full scene loads.

		return rayviz;
	}

	// For when you have a ray (and optionally a length)
	public static RayViz Create(
		Ray ray,
		float rayLength = DefaultRayLength,
		float lineWidth = DefaultLineWidth,
		float lifeTime = DefaultLifeTime)
	{
		return Create(
			startPoint: ray.origin,
			endPoint: ray.GetPoint(rayLength),
			lineWidth: lineWidth,
			lifeTime: lifeTime);
	}

	IEnumerator Start()
	{
		if (lifeTime > 0)
		{
			yield return new WaitForSeconds(lifeTime);
			Destroy(gameObject);
		}
	}
}

To use:

	Vector3 position = Vector3.zero;
	for (int i = 0; i < 10; i++)
	{
		RayViz.Create(position, position + Random.onUnitSphere * Random.Range( 0.5f, 5.0f));
	}
	Debug.Break();		// pause