Make objects between camera and character transparent - unity3d

Question

I'm working on a script for my camera to make objects between itself and the character transparent.
I managed to make it work with RayCast however I don't know how to restablish objects alpha value after they escape the ray.
This is my current code:
private void XRay() {
float characterDistance = Vector3.Distance(transform.position, GameObject.Find("Character").transform.position);
Vector3 fwd = transform.TransformDirection(Vector3.forward);
RaycastHit hit;
if (Physics.Raycast(transform.position, fwd, out hit, characterDistance)) {
// Add transparence
Color color = hit.transform.gameObject.renderer.material.color;
color.a = 0.5f;
hit.transform.gameObject.renderer.material.SetColor("_Color", color);
}
}

Answer 1

This is my final code. Note it only makes transparent one object at a time, but the same implementation can easily be done with RaycastAll and using an array for oldHits.
public class Camara : MonoBehaviour {
RaycastHit oldHit;
// Use this for initialization
void Start () {
}
// Update is called once per frame
void Update () {
}
void FixedUpdate() {
XRay ();
}
// Hacer a los objetos que interfieran con la vision transparentes
private void XRay() {
float characterDistance = Vector3.Distance(transform.position, GameObject.Find("Character").transform.position);
Vector3 fwd = transform.TransformDirection(Vector3.forward);
RaycastHit hit;
if (Physics.Raycast(transform.position, fwd, out hit, characterDistance)) {
if(oldHit.transform) {
// Add transparence
Color colorA = oldHit.transform.gameObject.renderer.material.color;
colorA.a = 1f;
oldHit.transform.gameObject.renderer.material.SetColor("_Color", colorA);
}
// Add transparence
Color colorB = hit.transform.gameObject.renderer.material.color;
colorB.a = 0.5f;
hit.transform.gameObject.renderer.material.SetColor("_Color", colorB);
// Save hit
oldHit = hit;
}
}
}

Answer 2

I did attach this script to my simple camera following the player. It might help you.
It can actually manage more than one obstructing the view and also you see I pass it a mask which I target with its name instead of checking for the collider name tag. Have fun.
using UnityEngine;
public class followPlayer : MonoBehaviour
{
public Transform player;
public Vector3 offset;
public Transform[] obstructions;
private int oldHitsNumber;
void Start()
{
oldHitsNumber = 0;
}
private void LateUpdate()
{
viewObstructed();
}
void Update()
{
transform.position = player.TransformPoint(offset);
transform.LookAt(player);
}
void viewObstructed()
{
float characterDistance = Vector3.Distance(transform.position, player.transform.position);
int layerNumber = LayerMask.NameToLayer("Walls");
int layerMask = 1 << layerNumber;
RaycastHit[] hits = Physics.RaycastAll(transform.position, player.position - transform.position, characterDistance, layerMask);
if (hits.Length > 0)
{ // Means that some stuff is blocking the view
int newHits = hits.Length - oldHitsNumber;
if (obstructions != null && obstructions.Length > 0 && newHits < 0)
{
// Repaint all the previous obstructions. Because some of the stuff might be not blocking anymore
for (int i = 0; i < obstructions.Length; i++)
{
obstructions[i].gameObject.GetComponent<MeshRenderer>().shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.On;
}
}
obstructions = new Transform[hits.Length];
// Hide the current obstructions
for (int i = 0; i < hits.Length; i++)
{
Transform obstruction = hits[i].transform;
obstruction.gameObject.GetComponent<MeshRenderer>().shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.ShadowsOnly;
obstructions[i] = obstruction;
}
oldHitsNumber = hits.Length;
}
else
{ // Mean that no more stuff is blocking the view and sometimes all the stuff is not blocking as the same time
if (obstructions != null && obstructions.Length > 0)
{
for (int i = 0; i < obstructions.Length; i++)
{
obstructions[i].gameObject.GetComponent<MeshRenderer>().shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.On;
}
oldHitsNumber = 0;
obstructions = null;
}
}
}
}