# Draw torus with a spot in the center

I would like to have a ring in my game with a center spot. The aim would be to move the ring up and down and receiving information about the position (x,y,z) of the spot. So far I achieved to move an imported CAD ring up and down. Now I have found a script to produce a torus however I got an error. What do I have to change in that script so that it works? Can I add a center spot to a torus? Thank you for your help.

Here the script code:

```
using System;
using UnityEngine;
using System.Collections;
public class TorusWire : MonoBehaviour {
[RequireComponent(typeof(MeshFilter),typeof(MeshRenderer))]
private static float Pi = 3.14159f;
public float segmentRadius = 1f;
public float tubeRadius = 0.1f;
public int segments = 32;
public int tubes = 12;
void Start() {
Torus();
}
public void Torus() {
// Total vertices
int totalVertices = segments * tubes;
// Total primitives
int totalPrimitives = totalVertices * 2;
// Total indices
int totalIndices = totalPrimitives * 3;
// Init vertexList and indexList
ArrayList verticesList = new ArrayList();
ArrayList indicesList = new ArrayList();
// Save these locally as floats
float numSegments = segments;
float numTubes = tubes;
// Calculate size of segment and tube
float segmentSize = 2 * Pi / numSegments;
float tubeSize = 2 * Pi / numTubes;
// Create floats for our xyz coordinates
float x = 0;
float y = 0;
float z = 0;
// Init temp lists with tubes and segments
ArrayList segmentList = new ArrayList();
ArrayList tubeList = new ArrayList();
// Loop through number of tubes
for (int i = 0; i < numSegments; i++)
{
tubeList = new ArrayList();
for (int j = 0; j < numTubes; j++)
{
// Calculate X, Y, Z coordinates.
x = (segmentRadius + tubeRadius * Mathf.Cos(j * tubeSize)) * Mathf.Cos(i * segmentSize);
y = (segmentRadius + tubeRadius * Mathf.Cos(j * tubeSize)) * Mathf.Sin(i * segmentSize);
z = tubeRadius * Mathf.Sin(j * tubeSize);
// Add the vertex to the tubeList
tubeList.Add(new Vector3(x, z, y));
// Add the vertex to global vertex list
verticesList.Add(new Vector3(x, z, y));
}
// Add the filled tubeList to the segmentList
segmentList.Add(tubeList);
}
// Loop through the segments
for (int i = 0; i < segmentList.Count; i++)
{
// Find next (or first) segment offset
int n = (i + 1) % segmentList.Count;
// Find current and next segments
ArrayList currentTube = (ArrayList)segmentList[i];
ArrayList nextTube = (ArrayList)segmentList[n];
// Loop through the vertices in the tube
for (int j = 0; j < currentTube.Count; j++)
{
// Find next (or first) vertex offset
int m = (j + 1) % currentTube.Count;
// Find the 4 vertices that make up a quad
Vector3 v1 = (Vector3)currentTube[j];
Vector3 v2 = (Vector3)currentTube[m];
Vector3 v3 = (Vector3)nextTube[m];
Vector3 v4 = (Vector3)nextTube[j];
// Draw the first triangle
indicesList.Add((int)verticesList.IndexOf(v1));
indicesList.Add((int)verticesList.IndexOf(v2));
indicesList.Add((int)verticesList.IndexOf(v3));
// Finish the quad
indicesList.Add((int)verticesList.IndexOf(v3));
indicesList.Add((int)verticesList.IndexOf(v4));
indicesList.Add((int)verticesList.IndexOf(v1));
}
}
Mesh mesh = new Mesh();
Vector3[] vertices = new Vector3[totalVertices];
verticesList.CopyTo(vertices);
int[] triangles = new int[totalIndices];
indicesList.CopyTo(triangles);
mesh.vertices = vertices;
mesh.triangles = triangles;
mesh.RecalculateBounds();
mesh.Optimize();
MeshFilter mFilter = GetComponent(typeof(MeshFilter)) as MeshFilter;
mFilter.mesh = mesh;
}
}
```

And here the error I got:

Assets/Scripts/TorusWire.cs(61,10): error CS0592: The attribute `UnityEngine.RequireComponent' is not valid on this declaration type. It is valid on `

class' declarations only

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