dem2terrain/src/util.js

使用 GDAL 制作 DEM 栅格的地形瓦片

const fs = require('fs');
const path = require('path');
const s4 = () => {
  return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
}

/**
 * 获取随机 uuid
 * @returns {string}
 */
const uuid = () => {
  return (s4() + s4() + '-' + s4() + '-' + s4() + '-' + s4() + '-' + s4() + s4() + s4());
}

function wait(ms) {
  return new Promise(resolve => setTimeout(() => resolve(), ms));
};
/**
 * 将毫秒转换为更合适显示的时间数字和单位
 * @param {number} timeInMs 
 * @returns {{
 *   resultTime: number;
 *   unit: 'ms' | 'sec' | 'min' | 'hour';
 * }}
 */
const prettyTime = (timeInMs) => {
  let result = 0
  let unit = 'ms'
  if (timeInMs < 1000) {
    result = timeInMs
  } else if (timeInMs < 60 * 1000) {
    result = timeInMs / 1000
    unit = 'sec'
  } else if (timeInMs < 60 * 60 * 1000) {
    result = timeInMs / (60 * 1000)
    unit = 'min'
  } else {
    result = timeInMs / (60 * 60 * 1000)
    unit = 'hour'
  }
  return {
    resultTime: result,
    unit
  }
}
//递归创建目录
function mkdirsSync(dirName) {
  if (fs.existsSync(dirName)) {
    return true;
  } else {
    if (mkdirsSync(path.dirname(dirName))) {
      fs.mkdirSync(dirName);
      return true;
    }
  }
}


/**
 * 清空文件夹下所有文件
 * @param {*} fold 
 */
function emptyDir(fold) {
  if(fs.existsSync(fold)===false)
    return;
  const files = fs.readdirSync(fold);
  files.forEach(file => {
    const filePath = path.join(fold, file);
    const stats = fs.statSync(filePath);
    if (stats.isDirectory()) {
      emptyDir(filePath);
      fs.rmdirSync(filePath);
    } else {
      fs.unlinkSync(filePath);
    }
  });
}


module.exports = {
  uuid, prettyTime, mkdirsSync, emptyDir, wait
}