Method getResFromScale

src/openlayers/mapping/WebMap.js:506–509

* @private * @function WebMap.prototype.getResFromScale * @description 将比例尺转换为分辨率 * @param {number} scale - 比例尺 * @param {string} coordUnit - 比例尺单位 * @param {number} dpi

(scale, coordUnit = 'DEGREE', dpi = 96)

   * @param {number} dpi
   */
  getResFromScale(scale, coordUnit = 'DEGREE', dpi = 96) {
    let mpu = metersPerUnit[coordUnit.toUpperCase()];
    return (scale * 0.0254) / dpi / mpu;
  }
  /**
   * @private
   * @function WebMap.prototype.getScaleFromRes