Question setting player set distance to object

Hello, I'm making a game and I want to make it so when the player collide with a planet, he start to orbit it and get to a fixed distance from it, I have been stuck for a few days and I have no idea where to begin. help pls?

Code (CSharp):

1. public class Movement : MonoBehaviour
2. {
3.     [SerializeField] private GameObject lastBestPlanet;
4.     [SerializeField] private GameObject closestPlanet;
5.     [SerializeField] private GameObject[] Planets;
6.     [SerializeField] private float rotatingSpeed = 135f;
7.     [SerializeField] private float flyingSpeed = 135f;
8.     [SerializeField] private float minDistance = 6.3f;
9.     [SerializeField] private Rigidbody2D rb2d;
10.     [SerializeField] private Vector3 direction;
11.     [SerializeField] private bool toFreeze = false;
12.  
13.     void Start() {
14.         rb2d = gameObject.GetComponent<Rigidbody2D>();
15.     }
16.     void Update()
17.     {
18.         getClosestPlanet(getPlanets());
19.         Rotate();
20.         if(Input.GetKeyDown(KeyCode.Space)) {
21.             Jump();
22.         }
23.         if(Input.GetKeyDown(KeyCode.Tab)) {
24.             Debug.Log(getClosestPlanet(getPlanets()));
25.             toFreeze = true;
26.         }
27.     }
28.  
29.     void Jump() {
30.         closestPlanet = getClosestPlanet(getPlanets());
31.         if (closestPlanet != null) {
32.             direction = closestPlanet.transform.position - transform.position;
33.         }
34.         rb2d.velocity = -1 * (direction.normalized * flyingSpeed * Time.deltaTime);
35.     }
36.  
37.     void Rotate() {
38.             getPlanets();
39.             closestPlanet = getClosestPlanet(Planets);
40.             if (closestPlanet != null) {
41.                 transform.RotateAround(closestPlanet.transform.position, Vector3.forward, -1 * 1 * rotatingSpeed * Time.deltaTime);
42.         }
43.     }
44.  
45.     GameObject[] getPlanets() {
46.         Planets = GameObject.FindGameObjectsWithTag("Planet");
47.         return Planets;
48.     }
49.  
50.     void snapToNewPlanet() {
51.         //closestPlanet = getClosestPlanet(getPlanets());
52.         Debug.Log("Snapped to a new Planet! :D");
53.         return;
54.     }
55.  
56.     GameObject getClosestPlanet (GameObject[] PlanetsArray)
57.     {
58.         GameObject bestPlanet = null;
59.         float closestDistanceSqr = Mathf.Infinity;
60.         Vector3 playerPosition = transform.position;
61.         foreach(GameObject Planet in PlanetsArray)
62.         {
63.             Vector3 directionToTarget = Planet.transform.position - playerPosition;
64.             float dSqrToTarget = directionToTarget.sqrMagnitude;
65.             //Debug.Log(dSqrToTarget);
66.             if(dSqrToTarget < closestDistanceSqr)
67.             {
68.                 closestDistanceSqr = dSqrToTarget;
69.                 if (closestDistanceSqr <= minDistance) {
70.  
71.                     bestPlanet = Planet;
72.                     if (bestPlanet != null && lastBestPlanet != bestPlanet) {
73.                         snapToNewPlanet();
74.                     }
75.                     lastBestPlanet = Planet;
76.                    
77.                 }
78.             }
79.         }
80.         if (bestPlanet == null && toFreeze) {
81.             Time.timeScale = 0;
82.             Debug.Log(closestDistanceSqr);
83.         }
84.    
85.         return bestPlanet;
86.     }
87. }

 

Actual orbital dynamics is hard. You would need a solver to predict course and accelerate / decelerate to enter orbit.

On the other hand if you just want to transition to an orbit instantly, that's easy:

Upon collision with the desired orbital height, parent the orbiting object to an invisible object colocated at the planet, then rotate that object.

 

The object don't collide, he stops around 2m from the planets. also, I want to make it so if he comes from the right down he will start orbiting from the right down. any ideas?

 

I get that. I'm saying make a DIFFERENT collider that is 2m larger than the planet, separated with layers so it collides with nothing else but the inbound to-be-orbited device, then connect it (parenting) and start spinning the inner thing.

So your planet prefab might look like:

MyPlanetPrefab

  VisiblePlanet

     SphericalGraphic

     CircleCollider2D for surface

  invisibleOrbitController <--- what slowly spins around at all times

     Invisible orbital Collider <---- what the inbound guy hits and gets parented to