skyquake/plugins/composer/src/src/libraries/zoomFactor.js

   1
   2 /*
   3  *
   4  *   Copyright 2016 RIFT.IO Inc
   5  *
   6  *   Licensed under the Apache License, Version 2.0 (the "License");
   7  *   you may not use this file except in compliance with the License.
   8  *   You may obtain a copy of the License at
   9  *
  10  *       http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *   Unless required by applicable law or agreed to in writing, software
  13  *   distributed under the License is distributed on an "AS IS" BASIS,
  14  *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *   See the License for the specific language governing permissions and
  16  *   limitations under the License.
  17  *
  18  */
  19 'use strict';
  20 export default function zoomFactor(element = document.body) {
  21         let factor;
  22         const rect = element.getBoundingClientRect();
  23         const physicalW = rect.right - rect.left;
  24         const logicalW = element.offsetWidth;
  25         factor = Math.round((physicalW / logicalW) * 100) / 100;
  26         // if fullscreen mode offsetWidth is 0
  27         if (isNaN(factor)) {
  28                 factor = 1;
  29         }
  30         return factor;
  31 }