3DTD/Assets/Scripts/Camera/HideWall.cs

using UnityEngine;

public class HideWall : MonoBehaviour
{

    [SerializeField] private GameObject target;
    [SerializeField] private GameObject origin;
    public GameObject prevObject;

    public Material defaultMaterial; // Material when not hitting "Wall"
    public Material hitMaterial; // Material when hitting "Wall"

    public float sphereRadius;
    float maxRayDistance;

    private void Start()
    {
        maxRayDistance = Vector3.Distance(target.transform.position, origin.transform.position) - sphereRadius * 2;
    }

    void Update()
    {
        Vector3 direction = (target.transform.position - origin.transform.position).normalized;

        RaycastHit[] hit;

        hit = Physics.SphereCastAll(origin.transform.position, sphereRadius, direction, maxRayDistance);

        for (int i = 0; i < hit.Length; i++)
        {
            if (hit[i].collider.CompareTag("Wall"))
            {
                if (prevObject != null)
                    if (prevObject == hit[i].collider.gameObject)
                    {
                        var renderer = hit[i].collider.GetComponent<Renderer>();
                        var originalMat = renderer.material;
                        var originalColor = originalMat.color;
                        originalMat.color = new Color(originalColor.r, originalColor.g, originalColor.b, 0f);
                        renderer.material = originalMat;
                    }
                    else
                    {
                        var renderer = prevObject.GetComponent<Collider>().GetComponent<Renderer>();
                        var originalMat = renderer.material;
                        var originalColor = originalMat.color;
                        originalMat.color = new Color(originalColor.r, originalColor.g, originalColor.b, 1f);
                        renderer.material = originalMat;
                    }

                prevObject = hit[i].collider.gameObject;
            }
        print(hit[i].collider.gameObject.name);
        }
    }

    private void OnDrawGizmos()
    {
        Gizmos.color = Color.red;
        Gizmos.DrawWireSphere(origin.transform.position, sphereRadius);
    }
}