Make objects between camera and character transparent

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;
        }
    }
}