使用 osmnx 下载英国边界会产生扭曲的国家轮廓

Question

我正在使用以下代码通过

osmnx

下载国家/地区边界：

country = ox.geocode_to_gdf(['United Kingdom'])
ax = ox.project_gdf(country).plot()

这会产生扭曲的

United Kingdom

轮廓，但似乎适用于其他国家/地区。

Answer 1

从 Nominatim 获取英国边界，而不是如JsFiddle 演示所示：

如果您希望减少边框细节，请将 &polygon_threshold=0.1 参数附加到我的 Javascript 代码中的 Nominatim

url

：

'use strict';

function processNominatimReply(data) {
  data.features.forEach(function(feature) {
    bordersGroup.addData(feature);
  });

  var bbox = data.features[0].bbox;
  var topLeft = L.latLng(bbox[1], bbox[0]);
  var bottomRight = L.latLng(bbox[3], bbox[2]);
  var countryBounds = L.latLngBounds(topLeft, bottomRight);

  var name = data.features[0].properties.display_name;
  var tooltip = L.tooltip()
    .setLatLng(countryBounds.getCenter())
    .setContent(name)
    .addTo(namesGroup);

  myMap.flyToBounds(countryBounds);
}

function sendNominatimRequest(countryCode) {
  var url = 'https://nominatim.openstreetmap.org/search' +
      '?polygon_geojson=1' +
      '&format=geojson' +
      '&country=' + countryCode;

  var request = new XMLHttpRequest();
  request.open('GET', url, true);
  request.onload = function() {
    if (this.status >= 200 && this.status < 400) {
      var data = JSON.parse(this.response);
      processNominatimReply(data);
    }
  };
  request.send();
}

var startPosition = [51.5072, 0.1276];
var myMap = L.map('myMap').setView(startPosition, 14);
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
  attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
}).addTo(myMap);

var namesGroup = L.layerGroup().addTo(myMap);
var bordersGroup = L.geoJSON().addTo(myMap);

var overlays = {
  'Show country names': namesGroup,
  'Show country borders': bordersGroup
};

L.control.layers(null, overlays, {
  collapsed: false
}).addTo(myMap);

sendNominatimRequest('uk');

html, body { 
  margin: 0;
  padding: 0;
}

#myMap {
  position: absolute;
  width: 100%;
  height: 100%;
}

<link href="https://cdn.jsdelivr.net/npm/leaflet@1/dist/leaflet.min.css" type="text/css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/leaflet@1/dist/leaflet-src.min.js"></script>

<div id="myMap"></div>