Question

本示例演示修改图形要素测试。

本示例演示修改图形要素测试。

main.js

import 'ol/ol.css';
import GeoJSON from 'ol/format/GeoJSON';
import Map from 'ol/Map';
import VectorLayer from 'ol/layer/Vector';
import VectorSource from 'ol/source/Vector';
import View from 'ol/View';
import {Circle as CircleStyle, Fill, Stroke, Style} from 'ol/style';
import {
  Modify,
  Select,
  defaults as defaultInteractions,
} from 'ol/interaction';

const styleFunction = (function () {
  const styles = {};
  const image = new CircleStyle({
    radius: 5,
    fill: null,
    stroke: new Stroke({color: 'orange', width: 2}),
  });
  styles['Point'] = new Style({image: image});
  styles['Polygon'] = new Style({
    stroke: new Stroke({
      color: 'blue',
      width: 3,
    }),
    fill: new Fill({
      color: 'rgba(0, 0, 255, 0.1)',
    }),
  });
  styles['MultiLineString'] = new Style({
    stroke: new Stroke({
      color: 'green',
      width: 3,
    }),
  });
  styles['MultiPolygon'] = new Style({
    stroke: new Stroke({
      color: 'yellow',
      width: 1,
    }),
    fill: new Fill({
      color: 'rgba(255, 255, 0, 0.1)',
    }),
  });
  styles['default'] = new Style({
    stroke: new Stroke({
      color: 'red',
      width: 3,
    }),
    fill: new Fill({
      color: 'rgba(255, 0, 0, 0.1)',
    }),
    image: image,
  });
  return function (feature) {
    return styles[feature.getGeometry().getType()] || styles['default'];
  };
})();

const geojsonObject = {
  'type': 'FeatureCollection',
  'crs': {
    'type': 'name',
    'properties': {
      'name': 'EPSG:3857',
    },
  },
  'features': [
    {
      'type': 'Feature',
      'geometry': {
        'type': 'Point',
        'coordinates': [0, 0],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'MultiPoint',
        'coordinates': [
          [-2e6, 0],
          [0, -2e6],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'LineString',
        'coordinates': [
          [4e6, -2e6],
          [8e6, 2e6],
          [9e6, 2e6],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'LineString',
        'coordinates': [
          [4e6, -2e6],
          [8e6, 2e6],
          [8e6, 3e6],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'Polygon',
        'coordinates': [
          [
            [-5e6, -1e6],
            [-4e6, 1e6],
            [-3e6, -1e6],
            [-5e6, -1e6],
          ],
          [
            [-4.5e6, -0.5e6],
            [-3.5e6, -0.5e6],
            [-4e6, 0.5e6],
            [-4.5e6, -0.5e6],
          ],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'MultiLineString',
        'coordinates': [
          [
            [-1e6, -7.5e5],
            [-1e6, 7.5e5],
          ],
          [
            [-1e6, -7.5e5],
            [-1e6, 7.5e5],
            [-5e5, 0],
            [-1e6, -7.5e5],
          ],
          [
            [1e6, -7.5e5],
            [15e5, 0],
            [15e5, 0],
            [1e6, 7.5e5],
          ],
          [
            [-7.5e5, -1e6],
            [7.5e5, -1e6],
          ],
          [
            [-7.5e5, 1e6],
            [7.5e5, 1e6],
          ],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'MultiPolygon',
        'coordinates': [
          [
            [
              [-5e6, 6e6],
              [-5e6, 8e6],
              [-3e6, 8e6],
              [-3e6, 6e6],
              [-5e6, 6e6],
            ],
          ],
          [
            [
              [-3e6, 6e6],
              [-2e6, 8e6],
              [0, 8e6],
              [0, 6e6],
              [-3e6, 6e6],
            ],
          ],
          [
            [
              [1e6, 6e6],
              [1e6, 8e6],
              [3e6, 8e6],
              [3e6, 6e6],
              [1e6, 6e6],
            ],
          ],
        ],
      },
    },
    {
      'type': 'Feature',
      'geometry': {
        'type': 'GeometryCollection',
        'geometries': [
          {
            'type': 'LineString',
            'coordinates': [
              [-5e6, -5e6],
              [0, -5e6],
            ],
          },
          {
            'type': 'Point',
            'coordinates': [4e6, -5e6],
          },
          {
            'type': 'Polygon',
            'coordinates': [
              [
                [1e6, -5e6],
                [2e6, -3.5e6],
                [3e6, -5e6],
                [1e6, -5e6],
              ],
            ],
          },
          {
            'type': 'Polygon',
            'coordinates': [
              [
                [1e6, -5e6],
                [2e6, -6.5e6],
                [3e6, -5e6],
                [1e6, -5e6],
              ],
            ],
          },
        ],
      },
    },
  ],
};

const source = new VectorSource({
  features: new GeoJSON().readFeatures(geojsonObject),
});

const layer = new VectorLayer({
  source: source,
  style: styleFunction,
});

const overlayStyle = (function () {
  const styles = {};
  styles['Polygon'] = [
    new Style({
      fill: new Fill({
        color: [255, 255, 255, 0.5],
      }),
    }),
    new Style({
      stroke: new Stroke({
        color: [255, 255, 255, 1],
        width: 5,
      }),
    }),
    new Style({
      stroke: new Stroke({
        color: [0, 153, 255, 1],
        width: 3,
      }),
    }),
  ];
  styles['MultiPolygon'] = styles['Polygon'];

  styles['LineString'] = [
    new Style({
      stroke: new Stroke({
        color: [255, 255, 255, 1],
        width: 5,
      }),
    }),
    new Style({
      stroke: new Stroke({
        color: [0, 153, 255, 1],
        width: 3,
      }),
    }),
  ];
  styles['MultiLineString'] = styles['LineString'];

  styles['Point'] = [
    new Style({
      image: new CircleStyle({
        radius: 7,
        fill: new Fill({
          color: [0, 153, 255, 1],
        }),
        stroke: new Stroke({
          color: [255, 255, 255, 0.75],
          width: 1.5,
        }),
      }),
      zIndex: 100000,
    }),
  ];
  styles['MultiPoint'] = styles['Point'];

  styles['GeometryCollection'] = styles['Polygon'].concat(styles['Point']);

  return function (feature) {
    return styles[feature.getGeometry().getType()];
  };
})();

const select = new Select({
  style: overlayStyle,
});

const modify = new Modify({
  features: select.getFeatures(),
  style: overlayStyle,
  insertVertexCondition: function () {
    // prevent new vertices to be added to the polygons
    return !select
      .getFeatures()
      .getArray()
      .every(function (feature) {
        return feature
          .getGeometry()
          .getType()
          .match(/Polygon/);
      });
  },
});

const map = new Map({
  interactions: defaultInteractions().extend([select, modify]),
  layers: [layer],
  target: 'map',
  view: new View({
    center: [0, 1000000],
    zoom: 2,
    multiWorld: true,
  }),
});

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Modify Features Test</title>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://unpkg.com/elm-pep"></script>
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v3/polyfill.min.js?features=fetch,requestAnimationFrame,Element.prototype.classList,URL,TextDecoder,Number.isInteger"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
      .map {
        background: grey;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <script src="main.js"></script>
  </body>
</html>

package.json

{
  "name": "modify-test",
  "dependencies": {
    "ol": "7.1.0"
  },
  "devDependencies": {
    "parcel": "^2.0.0-beta.1"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}