Draw rollercoaster dynamically using bezier

Hi,
I'm trying to make a game where people make a rollercoaster. I made it to the point where I instantiate a block called RailJoint where I click, it has the tag "st". Now I simply want to draw a bezier line between those RailJoints and draw a mesh over it. It isn't going to be a very complicated mesh, because I am not good at that . I tried this to make a bezier curve, but I couldn't let it draw between the RailJoints:

Code (JavaScript):

1. #pragma strict
2.  
3.    
4.     class Bezier extends System.Object {
5.      
6.      
7.         var p0 : Vector3;
8.         var p1 : Vector3;
9.         var p2 : Vector3;
10.         var p3 : Vector3;
11.      
12.         var ti : float = 0.0;
13.      
14.         private var b0 : Vector3 = Vector3.zero;
15.         private var b1 : Vector3 = Vector3.zero;
16.         private var b2 : Vector3 = Vector3.zero;
17.         private var b3 : Vector3 = Vector3.zero;
18.      
19.         private var Ax : float;
20.         private var Ay : float;
21.         private var Az : float;
22.      
23.         private var Bx : float;
24.         private var By : float;
25.         private var Bz : float;
26.    
27.         private var Cx : float;
28.         private var Cy : float;
29.         private var Cz : float;
30.    
31.         // Init function v0 = 1st point, v1 = handle of the 1st point , v2 = handle of the 2nd point, v3 = 2nd point
32.         // handle1 = v0 + v1
33.         // handle2 = v3 + v2
34.         function Bezier(v0 : Vector3, v1 : Vector3, v2 : Vector3, v3 : Vector3) {
35.             this.p0 = v0;
36.             this.p1 = v1;
37.             this.p2 = v2;
38.             this.p3 = v3;
39.         }
40.      
41.         // 0.0 >= t <= 1.0
42.         function GetPointAtTime(t : float) : Vector3 {
43.             this.CheckConstant();
44.             var t2 : float = t * t;
45.             var t3 : float = t * t * t;
46.             var x : float = this.Ax * t3 + this.Bx * t2 + this.Cx * t + p0.x;
47.             var y : float = this.Ay * t3 + this.By * t2 + this.Cy * t + p0.y;
48.             var z : float = this.Az * t3 + this.Bz * t2 + this.Cz * t + p0.z;
49.             return(Vector3(x,y,z));
50.          
51.         }
52.      
53.         private function SetConstant() {
54.             this.Cx = 3 * ((this.p0.x + this.p1.x) - this.p0.x);
55.             this.Bx = 3 * ((this.p3.x + this.p2.x) - (this.p0.x + this.p1.x)) - this.Cx;
56.             this.Ax = this.p3.x - this.p0.x - this.Cx - this.Bx;
57.          
58.             this.Cy = 3 * ((this.p0.y + this.p1.y) - this.p0.y);
59.             this.By = 3 * ((this.p3.y + this.p2.y) - (this.p0.y + this.p1.y)) - this.Cy;
60.             this.Ay = this.p3.y - this.p0.y - this.Cy - this.By;
61.    
62.             this.Cz = 3 * ((this.p0.z + this.p1.z) - this.p0.z);
63.             this.Bz = 3 * ((this.p3.z + this.p2.z) - (this.p0.z + this.p1.z)) - this.Cz;
64.             this.Az = this.p3.z - this.p0.z - this.Cz - this.Bz;
65.    
66.         }
67.    
68.         // Check if p0, p1, p2 or p3 have changed
69.         private function CheckConstant() {
70.             if (this.p0 != this.b0 || this.p1 != this.b1 || this.p2 != this.b2 || this.p3 != this.b3) {
71.                 this.SetConstant();
72.                 this.b0 = this.p0;
73.                 this.b1 = this.p1;
74.                 this.b2 = this.p2;
75.                 this.b3 = this.p3;
76.             }
77.         }
78.     }
79.    
80.    
81.     var myBezier : Bezier;
82.     private var t : float = 0.0;
83.    
84.     function Start() {
85.         myBezier = new Bezier(Vector3(-5,0,0), Random.insideUnitSphere * 2.0, Random.insideUnitSphere * 2.0, Vector3(5,0,0));
86.     }
87.    
88.     function Update () {
89.         var vec : Vector3 = myBezier.GetPointAtTime(t);
90.         transform.position = vec;
91.      
92.         t+= 0.001;
93.         if (t > 1.0)
94.             t = 0.0;
95.      
96.     }
97.    
98.  

Could anyone help me draw my rollercoaster? I would like it if it worked with unlimited RailJoints and if it loop around .

--Lucky

 

I made this to get you started.

 

Thx, I will take a look at it, see if I can work with it. Thx again

 

If you would like, I could send you the some updates on the game?

 

ThermalFusion, I have a script that instantiates your RailJoint prefab, but if I instantiate one, it says that the RailJoint has something in the script that isn't assigned, see error message at bottom. If I look at the script, in that spot it says this, but Unity doesn't take that .

ERROR:
NullReferenceException: Object reference not set to an instance of an object
RailJoint.Start () (at Assets/Rails/Scripts/RailJoint.cs:12)

EDIT:
It does recognize this, it doesn't know what RailPlacer is.

 

Oke, so now I use your scene, but I am going to modify the crap out of it . What I am going to do is make a 3d rail, make it use a modifyable terrain and make a cart ride it. Thx for your help

 

Oke, so how do I add my own mesh in? I tried this:

Code (CSharp):

1. mesh = (Mesh)Resources.Load("Assets/Rails/Models/RollercoasterRail",typeof(Mesh));
2.         mesh.name = "rail_mesh";
3.         mesh.MarkDynamic();
4.         GetComponent<MeshFilter>().sharedMesh = mesh;

but this doesn't load in anything?!? I checked if the mesh name inside RollercoasterRail blender file was actually rail_mesh, but do I need to make it an fbx?

 

What you are asking to do is rather complex. I dont mean to be harsh but you seem to be in way over your head. You are probably better off looking for a finished spline deformation system like MegaFiers. The solution I provided does not deform an existing mesh, it creates a new one procedurally, but you did not pick up on that. I should have explained it is a basic example that I provided. It does some of what you ask, but there is going to be a lot of extra effort needed to put in there.

 

Oke, so I am just reading a bit on procedurally generated meshes, so I might try to draw my own one then. But I know, this is probably way over my head, as I'm 15, but I'll try, because if I don't do anything, I won't learn anything new. Again, a big thank you, sir. You are the best

 

Oke, so I haven't started on the mesh part, but do you know how I can make the track more smooth? I already tried different settings, but it just won't work for me.

 

Nvm, lol, I forgot that rmb rotated stuff

 

There is also the steps variable on the manager. The rest is up to the bezier knots and tangents.