Y velocity going crazy when landing on a surface.

Hey there, so I have this rocket ship (It's just a triangle right now). When it lands on a surface It's Y velocity becomes something like "7.806205e-09" and never stops even though I'm not moving. I really need help sorting this out because I'm checking if the velocity magnitude is less than "0.9f" and if it is then I debug.log "Landed" however that never happens because of this issue.

My ship code:

Code (CSharp):

1. {
2.     Rigidbody2D rb;
3.  
4.     [SerializeField]
5.     private float _upwardsForce;
6.     [SerializeField]
7.     private float _fuel;
8.     [SerializeField]
9.     private float _currentVelocity;
10.  
11.     [SerializeField]
12.     private Text _fuelText;
13.     [SerializeField]
14.     private Text _velocityText;
15.  
16.     private void Start()
17.     {
18.         rb = GetComponent<Rigidbody2D>();
19.     }
20.  
21.     private void Update()
22.     {
23.         _fuelText.text = "Fuel: " + _fuel.ToString("0.0");
24.         _velocityText.text = "Velocity: " + rb.velocity.ToString("0.000");
25.  
26.         _currentVelocity = rb.velocity.magnitude;
27.  
28.         //RotateModule();
29.     }
30.  
31.     private void FixedUpdate()
32.     {
33.         UpwardsForce();
34.     }
35.  
36.     private void UpwardsForce()
37.     {
38.         if (Input.GetKey(KeyCode.W))
39.         {
40.             if (_currentVelocity > 3.5f)
41.                 return;
42.  
43.             if (_fuel > 0)
44.             {
45.                 rb.AddForce(transform.up * _upwardsForce, ForceMode2D.Force);
46.                 _fuel -= 0.5f;
47.             }
48.         }
49.         else if (Input.GetKey(KeyCode.A))
50.         {
51.             if (_currentVelocity > 2.5f)
52.                 return;
53.  
54.             if (_fuel > 0)
55.             {
56.                 rb.AddForce(-transform.right * _upwardsForce, ForceMode2D.Force);
57.                 _fuel -= 0.2f;
58.             }
59.         }
60.         else if (Input.GetKey(KeyCode.D))
61.         {
62.             if (_currentVelocity > 2.5f)
63.                 return;
64.  
65.             if (_fuel > 0)
66.             {
67.                 rb.AddForce(transform.right * _upwardsForce, ForceMode2D.Force);
68.                 _fuel -= 0.2f;
69.             }
70.         }
71.     }
72.  
73.     private void RotateModule()
74.     {
75.         if (Input.GetKey(KeyCode.Q))
76.         {
77.             transform.rotation *= Quaternion.Euler(0f, 0f, 1f);
78.             _fuel -= 0.1f;
79.         }
80.         else if (Input.GetKey(KeyCode.E))
81.         {
82.             transform.rotation *= Quaternion.Euler(0f, 0f, -1f);
83.             _fuel -= 0.1f;
84.         }
85.     }
86.  
87.     private void OnCollisionEnter2D(Collision2D collision)
88.     {
89.         if (collision.gameObject.CompareTag("Surface"))
90.         {
91.             if (rb.velocity.magnitude < -1.4f)
92.             {
93.                 Debug.Log("Safely Landed!");
94.             }
95.             else if (rb.velocity.magnitude > -1.6f)
96.             {
97.                 Debug.Log("Crashed!");
98.             }
99.         }
100.     }
101. }

 

Uh... 7.806205e-09 is less than 0.9f. Quite a lot less. Almost 0.9f less (as 7.806205e-09 is very very close to zero).

So I think the problem isn't what you think it is. Go back and focus on why your Debug.Log isn't firing when it should.

 

Hey, sorry for the late reply. I've figured it out. Thanks!

 

What was your issue, for us interested readers? I like your avatar image, by the way

 

Haha thank you, big fan of Mars! The issue was actually due to a weird rotation bug that happened whenever I land. So I just froze the rotation on the rigidbody component and manually code it through script. And I added a trigger collider slightly above the surface to detect the velocity rather than detecting it through normal collisions which seemed to better.

 

hey, nice looking Lunar Lander game!

 

Thank you! It was for a game jam