360 degree movement inside of cylinder

Hello everyone.

I've been scratching my head about this for a month now. How can I achieve a movement like the one here?

There's a cylinder, and the object sticks to the interior walls, effectively performing a 360 degree spin. Also, there's the issue of the cylinder bending in some parts, so it's effectively a magnetic field holding the object down (or up, or whichever way).

 

Which objects are you talking about? Obstacles or the player?

The obstacles look like they're a child of the tunnel. The player meanwhile either has something moving him down continuously kinda like gravity, or the player is positioned to be a specific distance from the tunnel's center. There could be a spline that runs down the center of the tunnel that can be used to position things a certain distance from the center.

 

As for rotations...

I'm pretty sure there's something representing the middle of the tunnel, even if it's not visible. The middle would be a line or a spline. You could rotate the player around using Transform.RotateAround() with the center line/spline as the axis of rotation.

 

I might try with Transform.RotateAround() for the player. Mind if I keep the thread for prototyping?

 

Feel free to keep the thread open, though you might get quicker and better answers by making a new concise topic for each specific problem you run into. Whatever works best for you!

 

I did something like this recently with my internal colony prototype for High Frontier.

This works by just beating the position and rotation into submission with math every frame. That is, I know that the camera is supposed to be a certain distance from the cylinder axis, and its "up" vector is supposed to point at the cylinder axis, so I just force it to the closest position/orientation that satisfies those constraints. Here's the code, in case there's anything useful in it for you:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class CylinderCamControl : MonoBehaviour {
5.  
6.     public float radius = 147;
7.     public float turnSpeed = 150;
8.     public float forwardSpeed = 10;
9.  
10.     void Update() {
11.         float boost = 1f;
12.         if (Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)) boost = 5f;
13.  
14.  
15.         transform.Rotate(0f, Input.GetAxis("Mouse X") * turnSpeed * Time.deltaTime, 0f);
16.  
17.         transform.position += transform.forward * Input.GetAxis("Vertical")
18.             * forwardSpeed * boost * Time.deltaTime;
19.  
20.         Snap();
21.     }
22.  
23.     void OnGUI() {
24.         if (Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)) {
25.             Rect r = new Rect(20, Screen.height-40, 100, 20);
26.             GUI.Label(r, "Super Speed");
27.         }
28.     }
29.  
30.     void Snap() {
31.         Vector3 pos = transform.position;
32.         float ang = Mathf.Atan2(pos.z, pos.x);
33.         Vector3 lookDir = transform.forward;
34.         pos.x = Mathf.Cos(ang) * radius;
35.         pos.z = Mathf.Sin(ang) * radius;
36.         transform.position = pos;
37.         Vector3 properUp = new Vector3(-pos.x, 0, -pos.z);
38.         Vector3 properLook = ProjectVectorOnPlane(properUp, lookDir);
39.         transform.rotation = Quaternion.LookRotation(properLook, properUp);
40.     }
41.  
42.     //Projects a vector onto a plane. The output is not normalized.
43.     static Vector3 ProjectVectorOnPlane(Vector3 planeNormal, Vector3 vector) {
44.         planeNormal.Normalize();
45.         return vector - (Vector3.Dot(vector, planeNormal) * planeNormal);
46.     }  
47. }
48.  

 

Alright, I made a little bit of progress.

http://labs.marcoff-weyland.com/BLS/BLD.html

Unfortunately, as you can see, the player only rotates to 90 degrees, -90 respectively, then stops. The forward/backward is broken, because it doesn't take into consideration the raycast.

Here's the movement code:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using System;
4.  
5. public class PlayerMovement : MonoBehaviour {
6.  
7.  
8.     public float Speed = 0;
9.     public float MaxSpeed = 1;
10.     public float rotationSpeed = 10;
11.     public float Acceleration = 10;
12.     public float Deceleration = 10;
13.     public Transform target;
14.     public float degrees = 10;
15.     // Use this for initialization
16.     void Start () {
17.    
18.     }
19.    
20.     // Update is called once per frame
21.     void Update () {
22.  
23.         if ((Input.GetKey ("w")) && (Speed < MaxSpeed))
24.             Speed = Speed - Acceleration * Time.deltaTime;
25.         else if ((Input.GetKey ("a")) && (Speed > -MaxSpeed))
26.             Speed = Speed + Acceleration * Time.deltaTime;
27.         else {
28.             if (Speed > Deceleration * Time.deltaTime)
29.                 Speed = Speed - Deceleration * Time.deltaTime;
30.             else if (Speed < -Deceleration * Time.deltaTime)
31.                 Speed = Speed + Deceleration * Time.deltaTime;
32.             else
33.                 Speed = 0;
34.         }
35.         transform.position = new Vector3 (transform.position.x, transform.position.y, transform.position.z + Speed * Time.deltaTime);
36.  
37.  
38.         RaycastHit rcHit;
39.        
40.         Vector3 theRay   = transform.TransformDirection(-Vector3.up);
41.        
42.         if (Physics.Raycast(transform.position, theRay, out rcHit))
43.         {
44.             float groundDis = rcHit.distance;
45.            
46.             transform.rotation = Quaternion.FromToRotation(Vector3.up,rcHit.normal);
47.            
48.             float movement = Input.GetAxis("Horizontal") * rotationSpeed * Time.deltaTime;
49.            
50.             transform.localPosition =
51.                 new Vector3(transform.localPosition.x + movement, (transform.localPosition.y -  groundDis)+.2f, transform.localPosition.z);          
52.            
53.         }
54.  
55.     }
56.  
57.     }
58.