1class CustomSinCurve extends THREE.Curve {
2  constructor(scale) {
3    super();
4    this.scale = scale;
5  }
6  getPoint(t) {
7    const tx = t * 3 - 1.5;
8    const ty = Math.sin(2 * Math.PI * t);
9    const tz = 0;
10    return new THREE.Vector3(tx, ty, tz).multiplyScalar(this.scale);
11  }
12}
13
14const path = new CustomSinCurve(4);
15const tubularSegments = 20;  
16const radius = 1;  
17const radialSegments = 8;  
18const closed = false;  
19const geometry = new THREE.TubeGeometry(
20    path, tubularSegments, radius, radialSegments, closed);