Generate H3 hexagons

.gitignore

node_modules/
package-lock.json
*.geojson
*.gpkg

README.md

Generate some H3 polygons

You need Node installed on your computer

Clone the repo then cd into it

Then do:

npm install
npm run generate # Run command in package.json file "node --max-old-space-size=8192 index.js" where 8192 = RAM. You may change it depending of your configuration

index.js

const geojson2h3 = require('geojson2h3');
const fs = require('fs');

const polygonEurope = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Polygon",
    "coordinates": [
      [
        [
          -11.953125,
          31.353636941500987
        ],
        [
          42.890625,
          31.353636941500987
        ],
        [
          42.890625,
          72.18180355624855
        ],
        [
          -11.953125,
          72.18180355624855
        ],
        [
          -11.953125,
          31.353636941500987
        ]
      ]
    ]
  }
};

for (let level = 0; level < 6; level++) {
  const hexagons = geojson2h3.featureToH3Set(polygonEurope, level);
  const featuresCollection = geojson2h3.h3SetToFeatureCollection(hexagons);  
  fs.writeFileSync(`./europe-${level}.geojson`, JSON.stringify(featuresCollection));
}

const polygonFrance = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Polygon",
    "coordinates": [
      [
        [
          -5.185546875,
          41.11246878918088
        ],
        [
          9.8876953125,
          41.11246878918088
        ],
        [
          9.8876953125,
          51.34433866059924
        ],
        [
          -5.185546875,
          51.34433866059924
        ],
        [
          -5.185546875,
          41.11246878918088
        ]
      ]
    ]
  }
};

for (let level = 6; level < 9; level++) {
  const hexagons = geojson2h3.featureToH3Set(polygonFrance, level);
  const featuresCollection = geojson2h3.h3SetToFeatureCollection(hexagons);  
  fs.writeFileSync(`./france-${level}.geojson`, JSON.stringify(featuresCollection));
}

const polygonPaysDeLaLoire = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Polygon",
    "coordinates": [
      [
        [
          -2.867431640625,
          46.210249600187225
        ],
        [
          0.9777832031250001,
          46.210249600187225
        ],
        [
          0.9777832031250001,
          48.60385760823255
        ],
        [
          -2.867431640625,
          48.60385760823255
        ],
        [
          -2.867431640625,
          46.210249600187225
        ]
      ]
    ]
  }
};

for (let level = 9; level < 10; level++) {
  const hexagons = geojson2h3.featureToH3Set(polygonPaysDeLaLoire, level);
  const featuresCollection = geojson2h3.h3SetToFeatureCollection(hexagons);  
  fs.writeFileSync(`./pays-de-la-loire-${level}.geojson`, JSON.stringify(featuresCollection));
}

const polygonNantes = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Polygon",
    "coordinates": [
      [
        [
          -1.6555023193359375,
          47.177112073280966
        ],
        [
          -1.4756011962890625,
          47.177112073280966
        ],
        [
          -1.4756011962890625,
          47.29692789291742
        ],
        [
          -1.6555023193359375,
          47.29692789291742
        ],
        [
          -1.6555023193359375,
          47.177112073280966
        ]
      ]
    ]
  }
};

for (let level = 10; level < 13; level++) {
  const hexagons = geojson2h3.featureToH3Set(polygonNantes, level);
  const featuresCollection = geojson2h3.h3SetToFeatureCollection(hexagons);  
  fs.writeFileSync(`./nantes-${level}.geojson`, JSON.stringify(featuresCollection));
}

package.json

{
  "name": "generate-h3",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "generate": "node --max-old-space-size=8192 index.js",
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "geojson2h3": "^1.0.1"
  }
}