docs: function getNumberOfTiles(options) {
  
    // Determine ground resolution if scale is only set
    determineGroundResolution(options.tiles.resolutions);
  
    // Counter of all tiles
    let countOfAllTiles = 0;
  
    // Calculate parameters of bbox
    let widthM = options.task.area.bbox.xmax - options.task.area.bbox.xmin;
    let heightM = options.task.area.bbox.ymax - options.task.area.bbox.ymin;
  
    // Iterate over all resolutions
    for (let int = 0; int < options.tiles.resolutions.length; int++) {
  
      // Current resolution
      let res = options.tiles.resolutions[int];
  
      // Size of all tiles in sum
      let widthPx = widthM / res.groundResolution;
      let heightPx = heightM / res.groundResolution;
  
      // Calculate tiles count of the current resolution
      let tiles = {};
      tiles.sizePx = options.tiles.maxSizePx - 2 * options.tiles.gutterPx;
      tiles.xCount = Math.ceil(widthPx / tiles.sizePx);
      tiles.yCount = Math.ceil(heightPx / tiles.sizePx);
  
      // Note tiles count of current resolution
      countOfAllTiles += tiles.xCount * tiles.yCount * options.wms.length;
    }
  
    return countOfAllTiles;
  }