Question How to do the the same SweepTest from Rigidbody in Rigidbody2D ?

Hello Everyone !

I have experience in programming, but I'm a beginner in Unity, so sorry if I ask some dumb things

I have a legacy project where 3D Physics was used for 2D game. And now I need to copy that Character Controller code and rewrite it for 2D Physic. Everything was fine till I faced SweepTest method.

I tried to write that method on my own using Rigidbody.Cast or Raycasts, but nothing helps

My character keeps falling from the edges(it must be on the ground all the time with slopes) and doesn't see walls correctly (so magnets to a wall, wall sliding, and wall jumping s**k too).

If I understood correctly SweepTest was used there to check left\right walls, ceiling, and ground. Velocity calculates based on those hits(for example, if we have hit to a wall -> we can calculate velocity to
magnetize character to that wall).

With 3D Physic everything works perfectly but with 2D and my versions of SweepTest it keeps failing on ground, failing from edges and everything I described later.

Thank you in advance

Here are some examples of my tries to recreate SweepTest for 2D(I have only one CapsuleCollider on my gameobject):

with Cast:

Code (CSharp):

1. public static bool SweepTest(this Rigidbody2D rb2D, Vector2 direction, float distance, out RaycastHit2D result)
2.         {
3.             var hits = new List<RaycastHit2D>();
4.             rb2D.Cast(direction, hits, distance);
5.  
6.             var attachedColliders = new List<Collider2D>();
7.             rb2D.GetAttachedColliders(attachedColliders);
8.            
9.             foreach (var hit in hits)
10.             {
11.                 if (hit.collider.isTrigger)
12.                     continue;
13.                
14.                 foreach (var attachedCollider in attachedColliders)
15.                 {
16.                     if (attachedCollider != hit.collider)
17.                     {
18.                         result = hit;
19.                         return true;
20.                     }
21.                 }
22.             }
23.  
24.             result = default;
25.             return false;
26. }

With Raycast:

Code (CSharp):

1. public static bool SweepTestRaycast(this Rigidbody2D rb2D, Vector2 direction, float distance, out RaycastHit2D result)
2.         {
3.             var attachedColliders = new List<Collider2D>();
4.             rb2D.GetAttachedColliders(attachedColliders);
5.             foreach (var attachedCollider in attachedColliders)
6.             {
7.                 var mesh = attachedCollider.CreateMesh(true, true);
8.                 foreach (var vertice in mesh.vertices)
9.                 {
10.                     Debug.DrawRay(vertice, direction, Color.red);
11.                     result = Physics2D.Raycast(vertice, direction, distance);
12.                    
13.                     if (result != null && result != (default) && result.collider != null)
14.                     {
15.                         var continueCheckForCollide = false;
16.                         foreach (var attachedColliderToCheck in attachedColliders)
17.                         {
18.                             if (result.collider == attachedColliderToCheck)
19.                             {
20.                                 continueCheckForCollide = true;
21.                                 break;
22.                             }
23.                         }
24.            
25.                         if (!continueCheckForCollide)
26.                         {
27.                             return true;
28.                         }
29.                     }
30.                 }
31.             }
32.            
33.             result = default;
34.             return false;
35. }

 

Yeaaaah) it's very awful This thing just drives me crazy I spent almost 3 weeks on this. It's not for Prod, so I simply tried multiple things and that was my last monster with the Raycast approach. I didn't want to do something similar with Cast, so came here for help

 

Thank you very much
At least now I know in which direction I need to go to find that little radiance at the end of the tunnel

Again thank you