troyz · October 19, 2017 03:14 · troyz · Oct 19, 2017
diff --git a/tile_caculator.js b/tile_caculator.js
 /**
 * 由18/19级的左上角/右下角瓦片，推导出20/21级的瓦片编码规则。
 * 依赖于[tile-lnglat-transform](https://github.com/CntChen/tile-lnglat-transform)
 */

 var TileLnglatTransform = require('../builds/index');

 var TileLnglatTransformBaidu = TileLnglatTransform.TileLnglatTransformBaidu;

 // 可以通过百度web地图获取18级的瓦片
 let level = 18;
 let data = {
    [level]: {
        // 左上角瓦片坐标
        leftTopTile: {
            tileX: 48566,
            tileY: 19307,
        },
        // 右下角瓦片坐标
        rightBottomTile: {
            tileX: 48570,
            tileY: 19303,
        },
    }
 };

 // 获取瓦片左上角点的经纬度
 function getLeftTopPixelLatLng(level)
 {
    let leftTopTile = data[level].leftTopTile;
    return TileLnglatTransformBaidu.pixelToLnglat(5, 251, leftTopTile.tileX, leftTopTile.tileY, level);
 }

 // 获取瓦片右下角点的经纬度
 function getRightBottomPixelLatLng(_level)
 {
    let rightBottomTile = data[_level].rightBottomTile;
    return TileLnglatTransformBaidu.pixelToLnglat(251, 5, rightBottomTile.tileX, rightBottomTile.tileY, _level);
 }

 for(let _level = level + 1; _level <= 21; _level++)
 {
    let leftTopLatLng = getLeftTopPixelLatLng(_level - 1);
    let rightBottomLatLng = getRightBottomPixelLatLng(_level - 1);

    let leftTopTile = TileLnglatTransformBaidu.lnglatToTile(leftTopLatLng.lng, leftTopLatLng.lat, _level);
    let rightBottomTile = TileLnglatTransformBaidu.lnglatToTile(rightBottomLatLng.lng, rightBottomLatLng.lat, _level);

    data[_level] = {
        leftTopTile: leftTopTile,
        rightBottomTile: rightBottomTile,
    };
 }

 console.log(JSON.stringify(data, null, 2));
	/**
	* 由18/19级的左上角/右下角瓦片，推导出20/21级的瓦片编码规则。
	* 依赖于[tile-lnglat-transform](https://github.com/CntChen/tile-lnglat-transform)
	*/

	var TileLnglatTransform = require('../builds/index');

	var TileLnglatTransformBaidu = TileLnglatTransform.TileLnglatTransformBaidu;

	// 可以通过百度web地图获取18级的瓦片
	let level = 18;
	let data = {
	[level]: {
	// 左上角瓦片坐标
	leftTopTile: {
	tileX: 48566,
	tileY: 19307,
	},
	// 右下角瓦片坐标
	rightBottomTile: {
	tileX: 48570,
	tileY: 19303,
	},
	}
	};

	// 获取瓦片左上角点的经纬度
	function getLeftTopPixelLatLng(level)
	{
	let leftTopTile = data[level].leftTopTile;
	return TileLnglatTransformBaidu.pixelToLnglat(5, 251, leftTopTile.tileX, leftTopTile.tileY, level);
	}

	// 获取瓦片右下角点的经纬度
	function getRightBottomPixelLatLng(_level)
	{
	let rightBottomTile = data[_level].rightBottomTile;
	return TileLnglatTransformBaidu.pixelToLnglat(251, 5, rightBottomTile.tileX, rightBottomTile.tileY, _level);
	}

	for(let _level = level + 1; _level <= 21; _level++)
	{
	let leftTopLatLng = getLeftTopPixelLatLng(_level - 1);
	let rightBottomLatLng = getRightBottomPixelLatLng(_level - 1);

	let leftTopTile = TileLnglatTransformBaidu.lnglatToTile(leftTopLatLng.lng, leftTopLatLng.lat, _level);
	let rightBottomTile = TileLnglatTransformBaidu.lnglatToTile(rightBottomLatLng.lng, rightBottomLatLng.lat, _level);

	data[_level] = {
	leftTopTile: leftTopTile,
	rightBottomTile: rightBottomTile,
	};
	}

	console.log(JSON.stringify(data, null, 2));