@openhps/core/dist/esm/three/helpers/ArrowHelper.js

Open Hybrid Positioning System - Core component

import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { BufferGeometry } from '../core/BufferGeometry.js';
import { Object3D } from '../core/Object3D.js';
import { CylinderGeometry } from '../geometries/CylinderGeometry.js';
import { MeshBasicMaterial } from '../materials/MeshBasicMaterial.js';
import { LineBasicMaterial } from '../materials/LineBasicMaterial.js';
import { Mesh } from '../objects/Mesh.js';
import { Line } from '../objects/Line.js';
import { Vector3 } from '../math/Vector3.js';
const _axis = /*@__PURE__*/new Vector3();
let _lineGeometry, _coneGeometry;

/**
 * An 3D arrow object for visualizing directions.
 *
 * ```js
 * const dir = new THREE.Vector3( 1, 2, 0 );
 *
 * //normalize the direction vector (convert to vector of length 1)
 * dir.normalize();
 *
 * const origin = new THREE.Vector3( 0, 0, 0 );
 * const length = 1;
 * const hex = 0xffff00;
 *
 * const arrowHelper = new THREE.ArrowHelper( dir, origin, length, hex );
 * scene.add( arrowHelper );
 * ```
 *
 * @augments Object3D
 */
class ArrowHelper extends Object3D {
  /**
   * Constructs a new arrow helper.
   *
   * @param {Vector3} [dir=(0, 0, 1)] - The (normalized) direction vector.
   * @param {Vector3} [origin=(0, 0, 0)] - Point at which the arrow starts.
   * @param {number} [length=1] - Length of the arrow in world units.
   * @param {(number|Color|string)} [color=0xffff00] - Color of the arrow.
   * @param {number} [headLength=length*0.2] - The length of the head of the arrow.
   * @param {number} [headWidth=headLength*0.2] - The width of the head of the arrow.
   */
  constructor(dir = new Vector3(0, 0, 1), origin = new Vector3(0, 0, 0), length = 1, color = 0xffff00, headLength = length * 0.2, headWidth = headLength * 0.2) {
    super();
    this.type = 'ArrowHelper';
    if (_lineGeometry === undefined) {
      _lineGeometry = new BufferGeometry();
      _lineGeometry.setAttribute('position', new Float32BufferAttribute([0, 0, 0, 0, 1, 0], 3));
      _coneGeometry = new CylinderGeometry(0, 0.5, 1, 5, 1);
      _coneGeometry.translate(0, -0.5, 0);
    }
    this.position.copy(origin);

    /**
     * The line part of the arrow helper.
     *
     * @type {Line}
     */
    this.line = new Line(_lineGeometry, new LineBasicMaterial({
      color: color,
      toneMapped: false
    }));
    this.line.matrixAutoUpdate = false;
    this.add(this.line);

    /**
     * The cone part of the arrow helper.
     *
     * @type {Mesh}
     */
    this.cone = new Mesh(_coneGeometry, new MeshBasicMaterial({
      color: color,
      toneMapped: false
    }));
    this.cone.matrixAutoUpdate = false;
    this.add(this.cone);
    this.setDirection(dir);
    this.setLength(length, headLength, headWidth);
  }

  /**
   * Sets the direction of the helper.
   *
   * @param {Vector3} dir - The normalized direction vector.
   */
  setDirection(dir) {
    // dir is assumed to be normalized

    if (dir.y > 0.99999) {
      this.quaternion.set(0, 0, 0, 1);
    } else if (dir.y < -0.99999) {
      this.quaternion.set(1, 0, 0, 0);
    } else {
      _axis.set(dir.z, 0, -dir.x).normalize();
      const radians = Math.acos(dir.y);
      this.quaternion.setFromAxisAngle(_axis, radians);
    }
  }

  /**
   * Sets the length of the helper.
   *
   * @param {number} length - Length of the arrow in world units.
   * @param {number} [headLength=length*0.2] - The length of the head of the arrow.
   * @param {number} [headWidth=headLength*0.2] - The width of the head of the arrow.
   */
  setLength(length, headLength = length * 0.2, headWidth = headLength * 0.2) {
    this.line.scale.set(1, Math.max(0.0001, length - headLength), 1); // see #17458
    this.line.updateMatrix();
    this.cone.scale.set(headWidth, headLength, headWidth);
    this.cone.position.y = length;
    this.cone.updateMatrix();
  }

  /**
   * Sets the color of the helper.
   *
   * @param {number|Color|string} color - The color to set.
   */
  setColor(color) {
    this.line.material.color.set(color);
    this.cone.material.color.set(color);
  }
  copy(source) {
    super.copy(source, false);
    this.line.copy(source.line);
    this.cone.copy(source.cone);
    return this;
  }

  /**
   * Frees the GPU-related resources allocated by this instance. Call this
   * method whenever this instance is no longer used in your app.
   */
  dispose() {
    this.line.geometry.dispose();
    this.line.material.dispose();
    this.cone.geometry.dispose();
    this.cone.material.dispose();
  }
}
export { ArrowHelper };