import * as THREE from 'three';


class TaperedLink extends THREE.Group {

  constructor(baseMaterial) {
    super();
    const geometry = new THREE.ConeGeometry( 0.75, 1, 32, true );
    const cplane = new THREE.Plane(new THREE.Vector3(0, -1, 0), 0.5);
    const material = baseMaterial.clone();
    material.clippingPlanes = [ cplane ];
    this.object = new THREE.Mesh( geometry, material );
    this.add( this.object );
  }  

  update(r1, r2, l) {
    const kraw = ( r1 - r2 );
    const k = ( kraw == 0 ) ? 0.001 : kraw;
    if( k > 0 ) {
      const h = l * r1 / k;
      this.object.scale.copy(new THREE.Vector3(r1, h, r1));
      this.object.material.clippingPlanes[0].normal.y = -1;
      this.object.material.clippingPlanes[0].constant = l / 2;
      this.object.position.copy(new THREE.Vector3(0, h/2 - l/2, 0));
    } else {
      const h = l * r2 / k;
      this.object.scale.copy(new THREE.Vector3(r2, h, r2));
      this.object.material.clippingPlanes[0].normal.y = 1;
      this.object.material.clippingPlanes[0].constant = l / 2;
      this.object.position.copy(new THREE.Vector3(0, h / 2 + l / 2, 0));
    }
  }

}

export { TaperedLink };