Fix lag for field of view shadow generation.

I have been working on creating a field of view script in unity. It is very inefficient and was thrown together without consideration for performance. I decided to make it, because using the regular shadow system was what I wanted, and each object required a script. There is also a problem with the shadows being jittery. Is there anything I can do to fix it, and if not, are there other good alternatives?

Script- Basically just casts a bunch of rays and creates meshes over them.

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using System.Collections.Generic;
4. using UnityEditor;
5.  
6. public class fieldofview : MonoBehaviour {
7.  
8.     public LayerMask targetMask;
9.     public float radius;
10.     public int NumberOfRays;
11.  
12.     private Vector2 LastStart;
13.     private Vector2 LastEnd;
14.     private bool Last;
15.  
16.     public GameObject MeshHolder;
17.     public GameObject Mesh;
18.  
19.     public void Start(){
20.         for (int i = 0; i < NumberOfRays; i++){
21.             GameObject shadow = Instantiate(Mesh, new Vector2(0, 0), Quaternion.identity);
22.             shadow.transform.SetParent(MeshHolder.transform);
23.         }
24.     }
25.  
26.     void Update(){
27.         for (int i = 0; i < NumberOfRays; i++){
28.             Mesh mesh = MeshHolder.transform.GetChild(i).GetComponent<MeshFilter>().mesh;
29.             Vector3[] vertices = mesh.vertices;
30.             Vector3[] normals = mesh.normals;
31.             MeshHolder.transform.GetChild(i).gameObject.SetActive(true);
32.  
33.             var dir = Quaternion.Euler(0, 0, i * 360/NumberOfRays) * transform.right;
34.             Vector3 startPosition = transform.position;
35.             Vector3 endPosition = dir * radius + transform.position;
36.  
37.             RaycastHit2D hit = Physics2D.Linecast(startPosition, endPosition, targetMask);
38.  
39.             if(hit.collider != null){
40.                 if(Last){
41.                     Vector3[] setvertices = new Vector3[4]{
42.                         new Vector2(LastStart.x, LastStart.y),
43.                         new Vector2(LastEnd.x, LastEnd.y),
44.                         new Vector2(hit.point.x, hit.point.y),
45.                         new Vector2(endPosition.x, endPosition.y)
46.                     };
47.                     mesh.vertices = setvertices;
48.                     mesh.RecalculateBounds();
49.                 }else MeshHolder.transform.GetChild(i).gameObject.SetActive(false);
50.                 LastStart = hit.point;
51.                 LastEnd = endPosition;
52.                 Last = true;
53.  
54.                 Debug.DrawLine(hit.point, endPosition, Color.green);
55.             }else {
56.                 Last = false;
57.                 MeshHolder.transform.GetChild(i).gameObject.SetActive(false);
58.             }
59.         }
60.     }
61. }

Output-


I am have a problem of

 

Thank you MelevMay for pointing out the Collider2D check. I fixed the major lag by removing it (it was from some other testing and I forgot to take it out), but I still have some problems. To make the shadows look good, I have to set the rays to something like 1000. This obviously causes lag. Also, the shadows are also a bit jittery.

 

And instead of casting thousands of rays and lagging the game, how would I go about casting a ray to each closest edge?

what I am doing

What I want to do