tui-code-snippet/domEvent/getMousePosition.js

TOAST UI Utility: CodeSnippet

/**
 * @fileoverview Get mouse position from mouse event
 * @author NHN FE Development Lab <dl_javascript@nhn.com>
 */

'use strict';

var isArray = require('../type/isArray');

/**
 * Get mouse position from mouse event
 *
 * If supplied relatveElement parameter then return relative position based on
 *  element
 * @param {(MouseEvent|object|number[])} position - mouse position object
 * @param {HTMLElement} relativeElement HTML element that calculate relative
 *  position
 * @returns {number[]} mouse position
 * @memberof module:domEvent
 */
function getMousePosition(position, relativeElement) {
  var positionArray = isArray(position);
  var clientX = positionArray ? position[0] : position.clientX;
  var clientY = positionArray ? position[1] : position.clientY;
  var rect;

  if (!relativeElement) {
    return [clientX, clientY];
  }

  rect = relativeElement.getBoundingClientRect();

  return [
    clientX - rect.left - relativeElement.clientLeft,
    clientY - rect.top - relativeElement.clientTop
  ];
}

module.exports = getMousePosition;