core2d/src/Touch.mjs

Multiplatform 2D interaction engine

"use strict";

import { Point } from "./Point.mjs";

export class Touch extends Point {
  constructor(event) {
    super();
    event.preventDefault();
    this._isDown = true;
    this.updateCoordinates(event);

    addEventListener(
      "touchend",
      (event) => {
        event.preventDefault();
        this._isDown = false;
        this.updateCoordinates(event);
      },
      false
    );

    addEventListener(
      "touchmove",
      (event) => {
        event.preventDefault();
        this.updateCoordinates(event);
      },
      false
    );

    addEventListener(
      "touchstart",
      () => {
        event.preventDefault();
        this._isDown = true;
        this.updateCoordinates(event);
      },
      false
    );
  }

  get command() {
    return this._isDown;
  }

  updateCoordinates(event) {
    const TOUCHES = event.changedTouches;
    const TOUCH = TOUCHES[0];
    this.x = TOUCH.pageX;
    this.y = TOUCH.pageY;
  }
}