Arrow.cs

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class Arrow : MonoBehaviour {
  [Header("Information")]
  public bool isSelected = true;
  public float distance = 0;

  [Header("Initialization")]
  public LineRenderer line;
  public GameObject arrowHead;
  public Camera specialCamera;

  void Update () {
    if (isSelected) {
      RaycastHit hit;
      Ray ray = (specialCamera? specialCamera: Camera.main).ScreenPointToRay(Input.mousePosition);

      if (Physics.Raycast(ray, out hit)) {
        line.SetPosition(1, hit.point + hit.normal * 0.05f);
        arrowHead.transform.position = line.GetPosition(1);
        arrowHead.transform.forward = line.GetPosition(0) - line.GetPosition(1);
      }

      if (Input.GetMouseButtonUp(1)) {
        isSelected = false;
        if (!ArrowPorter.selected) {
          Destroy(gameObject);
        }
      }
    } // else {
    //   RaycastHit hit;
    //   Ray ray = (specialCamera? specialCamera: Camera.main).ScreenPointToRay(Input.mousePosition);

    //   if (Physics.Raycast(ray, out hit)) {
    //     Vector3 direction = line.GetPosition(0);
    //     Vector3 startingPoint = line.GetPosition(1);

    //     Ray r = new Ray(startingPoint, direction);
    //     distance = Vector3.Cross(r.direction, hit.point).magnitude;
    //   } else {
    //     distance = Mathf.Infinity;
    //   }
    // }
  }
}