CDSS-daming-web/node_modules/echarts/lib/coord/geo/parseGeoJson.js

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied.  See the License for the
* specific language governing permissions and limitations
* under the License.
*/


/**
 * AUTO-GENERATED FILE. DO NOT MODIFY.
 */

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied.  See the License for the
* specific language governing permissions and limitations
* under the License.
*/

/**
 * Parse and decode geo json
 */
import * as zrUtil from 'zrender/lib/core/util';
import { GeoJSONRegion } from './Region';

function decode(json) {
  if (!json.UTF8Encoding) {
    return json;
  }

  var jsonCompressed = json;
  var encodeScale = jsonCompressed.UTF8Scale;

  if (encodeScale == null) {
    encodeScale = 1024;
  }

  var features = jsonCompressed.features;

  for (var f = 0; f < features.length; f++) {
    var feature = features[f];
    var geometry = feature.geometry;

    if (geometry.type === 'Polygon') {
      var coordinates = geometry.coordinates;

      for (var c = 0; c < coordinates.length; c++) {
        coordinates[c] = decodePolygon(coordinates[c], geometry.encodeOffsets[c], encodeScale);
      }
    } else if (geometry.type === 'MultiPolygon') {
      var coordinates = geometry.coordinates;

      for (var c = 0; c < coordinates.length; c++) {
        var coordinate = coordinates[c];

        for (var c2 = 0; c2 < coordinate.length; c2++) {
          coordinate[c2] = decodePolygon(coordinate[c2], geometry.encodeOffsets[c][c2], encodeScale);
        }
      }
    }
  } // Has been decoded


  jsonCompressed.UTF8Encoding = false;
  return jsonCompressed;
}

function decodePolygon(coordinate, encodeOffsets, encodeScale) {
  var result = [];
  var prevX = encodeOffsets[0];
  var prevY = encodeOffsets[1];

  for (var i = 0; i < coordinate.length; i += 2) {
    var x = coordinate.charCodeAt(i) - 64;
    var y = coordinate.charCodeAt(i + 1) - 64; // ZigZag decoding

    x = x >> 1 ^ -(x & 1);
    y = y >> 1 ^ -(y & 1); // Delta deocding

    x += prevX;
    y += prevY;
    prevX = x;
    prevY = y; // Dequantize

    result.push([x / encodeScale, y / encodeScale]);
  }

  return result;
}

export default function parseGeoJSON(geoJson, nameProperty) {
  geoJson = decode(geoJson);
  return zrUtil.map(zrUtil.filter(geoJson.features, function (featureObj) {
    // Output of mapshaper may have geometry null
    return featureObj.geometry && featureObj.properties && featureObj.geometry.coordinates.length > 0;
  }), function (featureObj) {
    var properties = featureObj.properties;
    var geo = featureObj.geometry;
    var geometries = [];

    if (geo.type === 'Polygon') {
      var coordinates = geo.coordinates;
      geometries.push({
        type: 'polygon',
        // According to the GeoJSON specification.
        // First must be exterior, and the rest are all interior(holes).
        exterior: coordinates[0],
        interiors: coordinates.slice(1)
      });
    }

    if (geo.type === 'MultiPolygon') {
      var coordinates = geo.coordinates;
      zrUtil.each(coordinates, function (item) {
        if (item[0]) {
          geometries.push({
            type: 'polygon',
            exterior: item[0],
            interiors: item.slice(1)
          });
        }
      });
    }

    var region = new GeoJSONRegion(properties[nameProperty || 'name'], geometries, properties.cp);
    region.properties = properties;
    return region;
  });
}