基于JS实现《国家基本比例尺地形图分幅和编号》标准

本文主要是介绍基于JS实现《国家基本比例尺地形图分幅和编号》标准，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

1、标准

GB T 13989-2012国家基本比例尺地形图分幅和编号

地址：【高清版】GB T 13989-2012国家基本比例尺地形图分幅和编号 - 道客巴巴

2、1:100万比例尺

2.1 说明

2.2 计算公式

2.3 计算代码

2.3.1 元素数据定义

由于中国只到N层，所以只定义到O.

/*** 100万比例尺下的行号对应的代码*/static mateData100 = [{rowCode: "A",rowNumber: 1,},{rowCode: "B",rowNumber: 2,},{rowCode: "C",rowNumber: 3,},{rowCode: "D",rowNumber: 4,},{rowCode: "E",rowNumber: 5,},{rowCode: "F",rowNumber: 6,},{rowCode: "G",rowNumber: 7,},{rowCode: "H",rowNumber: 8,},{rowCode: "I",rowNumber: 9,},{rowCode: "J",rowNumber: 10,},{rowCode: "K",rowNumber: 11,},{rowCode: "L",rowNumber: 12,},{rowCode: "M",rowNumber: 13,},{rowCode: "N",rowNumber: 14,},{rowCode: "O",rowNumber: 15,},];

2.3.2 代码实现

/*** 根据经纬度计算100万比例尺的行列号* @param lon* @param lat* @return {{col: number, row: number, code: string}}*/static calcMapFrameNumber100 = (lon, lat) => {let a = Math.trunc(lat / 4.0) + 1;let b = Math.trunc(lon / 6.0) + 31;let mateInfo = MapFrameUtils.mateData100.find((item) => item.rowNumber === a);return {row: a,col: b,code: mateInfo.rowCode,};};

3、非100万比例尺

3.1 说明

3.1.1 2000到50万比例尺格式

3.1.2 500到1000比例尺格式

3.2 计算公式

3.3 代码

3.3.1 元数据

/*** 100万比例尺下的行号对应的代码*/static mateData100 = [{rowCode: "A",rowNumber: 1,},{rowCode: "B",rowNumber: 2,},{rowCode: "C",rowNumber: 3,},{rowCode: "D",rowNumber: 4,},{rowCode: "E",rowNumber: 5,},{rowCode: "F",rowNumber: 6,},{rowCode: "G",rowNumber: 7,},{rowCode: "H",rowNumber: 8,},{rowCode: "I",rowNumber: 9,},{rowCode: "J",rowNumber: 10,},{rowCode: "K",rowNumber: 11,},{rowCode: "L",rowNumber: 12,},{rowCode: "M",rowNumber: 13,},{rowCode: "N",rowNumber: 14,},{rowCode: "O",rowNumber: 15,},];

3.3.2 实现代码

/*** 根据比例尺，经纬度计算地图的行列号* @param scale* @param lon* @param lat* @return {{col: number, code: *, row: number, digit: (number|*)}|null}*/static calcMapFrameNumberNot100 = (scale, lon, lat) => {let mateData = MapFrameUtils.mateData.find((item) => item.scale === scale);if (mateData) {let cStep = ((lat % 4) / mateData.latD).toPrecision(4);let c = Math.round(4 / mateData.latD - Math.trunc(Number(cStep)));let dStep = ((lon % 6) / mateData.lonD).toPrecision(4);let d = Math.trunc(Number(dStep)) + 1;return {row: c,col: d,code: mateData.code,digit: mateData.digit,};} else {return null;}};

4、综合代码

/*** 采用标准：国家基本比例尺地形图分幅和编号《GB/T 13989-2012》* 1、根据经纬度计算图幅号* 2、根据图幅号图幅范围计算* 3、定义图幅信息*/
export default class MapFrameUtils {/*** 根据经纬度计算100万比例尺的行列号* @param lon* @param lat* @return {{col: number, row: number, code: string}}*/static calcMapFrameNumber100 = (lon, lat) => {let a = Math.trunc(lat / 4.0) + 1;let b = Math.trunc(lon / 6.0) + 31;let mateInfo = MapFrameUtils.mateData100.find((item) => item.rowNumber === a);return {row: a,col: b,code: mateInfo.rowCode,};};/*** 根据比例尺，经纬度计算地图的行列号* @param scale* @param lon* @param lat* @return {{col: number, code: *, row: number, digit: (number|*)}|null}*/static calcMapFrameNumberNot100 = (scale, lon, lat) => {let mateData = MapFrameUtils.mateData.find((item) => item.scale === scale);if (mateData) {let cStep = ((lat % 4) / mateData.latD).toPrecision(4);let c = Math.round(4 / mateData.latD - Math.trunc(Number(cStep)));let dStep = ((lon % 6) / mateData.lonD).toPrecision(4);let d = Math.trunc(Number(dStep)) + 1;return {row: c,col: d,code: mateData.code,digit: mateData.digit,};} else {return null;}};/*** 根据计算出来的行列号，比例尺，计算该格网在地图商的范围* @param frame100* @param frameNot100* @param scale* @return {{minY: number, minX: number, maxY: number, maxX: number}}*/static calcMapFrameExtent = (frame100, frameNot100, scale) => {let mateData = MapFrameUtils.mateData.find((item) => item.scale === scale);let lon = (frame100.col - 31) * 6 + (frameNot100.col - 1) * mateData.lonD;let lat =(frame100.row - 1) * 4 +(4 / mateData.latD - frameNot100.row) * mateData.latD;return {minX: lon,minY: lat,maxX: lon + mateData.lonD,maxY: lat + mateData.latD,};};/*** 根据比例尺和经纬度，获取所在图幅范围的编号、行列号以及范围* @param scale* @param lon* @param lat* @return {null|{extent: {minY: number, minX: number, maxY: number, maxX: number}, col: number, code: string, row: number}}*/static calcMapFrameNumber = (scale, lon, lat) => {let mapFrameNumber100 = MapFrameUtils.calcMapFrameNumber100(lon, lat);let mapFrameNumberNot100 = MapFrameUtils.calcMapFrameNumberNot100(scale,lon,lat);if (mapFrameNumberNot100) {let code =mapFrameNumber100.code +"" +mapFrameNumber100.col +"" +mapFrameNumberNot100.code +"" +mapFrameNumberNot100.row.toString().padStart(mapFrameNumberNot100.digit, "0") +"" +mapFrameNumberNot100.col.toString().padStart(mapFrameNumberNot100.digit, "0");let extent = MapFrameUtils.calcMapFrameExtent(mapFrameNumber100,mapFrameNumberNot100,scale);return {code: code,extent: extent,row: mapFrameNumberNot100.row,col: mapFrameNumberNot100.col,};} else {return null;}};/*** 100万比例尺下的行号对应的代码*/static mateData100 = [{rowCode: "A",rowNumber: 1,},{rowCode: "B",rowNumber: 2,},{rowCode: "C",rowNumber: 3,},{rowCode: "D",rowNumber: 4,},{rowCode: "E",rowNumber: 5,},{rowCode: "F",rowNumber: 6,},{rowCode: "G",rowNumber: 7,},{rowCode: "H",rowNumber: 8,},{rowCode: "I",rowNumber: 9,},{rowCode: "J",rowNumber: 10,},{rowCode: "K",rowNumber: 11,},{rowCode: "L",rowNumber: 12,},{rowCode: "M",rowNumber: 13,},{rowCode: "N",rowNumber: 14,},{rowCode: "O",rowNumber: 15,},];/*** 非100万情况下，不同比例尺的原始数据*/static mateData = [{scale: 500000,label: "1:50万",lonD: 3,latD: 2,code: "B",digit: 3,},{scale: 250000,label: "1:25万",lonD: 1.5,latD: 1,code: "C",digit: 3,},{scale: 100000,label: "1:10万",lonD: 0.5,latD: 0.33333333,code: "D",digit: 3,},{scale: 50000,label: "1:5万",lonD: 0.25,latD: 0.16666667,code: "E",digit: 3,},{scale: 25000,label: "1:2.5万",lonD: 0.125,latD: 0.08333333,code: "F",digit: 3,},{scale: 10000,label: "1:1万",lonD: 0.0625,latD: 0.04166667,code: "G",digit: 3,},{scale: 5000,label: "1:5000",lonD: 0.03125,latD: 0.02083333,code: "H",digit: 3,},{scale: 2000,label: "1:2000",lonD: 0.01041667,latD: 0.006944444,code: "I",digit: 3,},{scale: 1000,label: "1:1000",lonD: 0.005208333,latD: 0.003472222,code: "J",digit: 4,},{scale: 500,label: "1:500",lonD: 0.002603889,latD: 0.001736111,code: "K",digit: 4,},];
}

5、测试结果

5.1 测试代码

MapFrameUtils.mateData.forEach((item) => {let mapFrame = MapFrameUtils.calcMapFrameNumber(item.scale, 114.5625, 39.375);console.log(item.scale, mapFrame);
});