InputManager.js

import * as THREE from 'three';
import { updateStatus } from './utils';
import { World } from './world';
class InputManager {
  /**
   * @type {THREE.Raycaster}
   */
  raycaster = new THREE.Raycaster();
  /**
   * @type {THREE.Camera}
   */
  camera = null;
  /**
   * @type {World}
   */
  world = null;
  constructor() {
    this.raycaster.layers.disable(1);
  }
  initialize(camera, world) {
    this.camera = camera;
    this.world = world;
  }
  /**
   * Wait for the player to choose a target square
   * @returns {Promise<Vector3 | null>}
   */
  async getTargetSquare() {
    updateStatus('Select a target square');
    return new Promise((resolve) => {
      /**
       * Event handler when user clicks on the screen
       * @param {MouseEvent} event 
       */
      const onMouseDown = (event) => {
        const coords = new THREE.Vector2(
          (event.clientX / window.innerWidth) * 2 - 1,
          - (event.clientY / window.innerHeight) * 2 + 1
        );
        this.raycaster.setFromCamera(coords, this.camera);
        const intersections = this.raycaster.intersectObject(this.world.terrain);
        if (intersections.length > 0) {
          const selectedCoords = new THREE.Vector3(
            Math.floor(intersections[0].point.x),
            0,
            Math.floor(intersections[0].point.z)
          );
          window.removeEventListener('mousedown', onMouseDown);
          resolve(selectedCoords);
        }
      };
      // Wait for player to select a square
      window.addEventListener('mousedown', onMouseDown);
    });
  }
  /**
   * Wait for the player to choose a target GameObject
   * @returns {Promise<GameObject | null>}
   */
  async getTargetObject() {
    updateStatus('Select a target object');
    return new Promise((resolve) => {
      /**
       * Event handler when user clicks on the screen
       * @param {MouseEvent} event 
       */
      const onMouseDown = (event) => {
        const coords = new THREE.Vector2(
          (event.clientX / window.innerWidth) * 2 - 1,
          - (event.clientY / window.innerHeight) * 2 + 1
        );
        this.raycaster.setFromCamera(coords, this.camera);
        const intersections = this.raycaster.intersectObject(this.world.objects, true);
        if (intersections.length > 0) {
          // Intersection is occurring with the mesh
          // The parent of the mesh is the GameObject
          const selectedObject = intersections[0].object.parent;
          window.removeEventListener('mousedown', onMouseDown);
          resolve(selectedObject);
        }
      };
      window.addEventListener('mousedown', onMouseDown);
    });
  }
}
const inputManager = new InputManager();
export default inputManager;