https://github.com/mmadfox/go-geojson2h3

Conversion utilities between H3 indexes and GeoJSON
https://github.com/mmadfox/go-geojson2h3

geojson go h3 hexagon spatial uber-h3

Last synced: about 1 month ago
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Conversion utilities between H3 indexes and GeoJSON

• Host: GitHub
• URL: https://github.com/mmadfox/go-geojson2h3
• Owner: mmadfox
• License: mit
• Created: 2022-05-06T17:28:57.000Z (over 2 years ago)
• Default Branch: main
• Last Pushed: 2022-05-11T10:56:34.000Z (over 2 years ago)
• Last Synced: 2024-07-31T20:51:46.625Z (5 months ago)
• Topics: geojson, go, h3, hexagon, spatial, uber-h3
• Language: Go
• Homepage:
• Size: 22.5 KB
• Stars: 3
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-go - H3 GeoJSON - Conversion utilities between H3 indexes and GeoJSON. (Geographic / Search and Analytic Databases)
• awesome-go-extra - go-geojson2h3 - 05-06T17:28:57Z|2022-05-11T10:56:34Z| (Geographic / Advanced Console UIs)

README

        
# go-geojson2h3

[![Coverage Status](https://coveralls.io/repos/github/mmadfox/go-geojson2h3/badge.svg?branch=main&n=1)](https://coveralls.io/github/mmadfox/go-geojson2h3?branch=main&n=1)

[![Documentation](https://godoc.org/github.com/mmadfox/go-geojson2h3?status.svg)](https://pkg.go.dev/github.com/mmadfox/go-geojson2h3)

[![Go Report Card](https://goreportcard.com/badge/github.com/mmadfox/go-geojson2h3)](https://goreportcard.com/report/github.com/mmadfox/go-geojson2h3)

The `geojson2h3` library includes a set of utilities for conversion between GeoJSON Objects: 

* Point, MultiPoint,

* LineString, MultiLineString

* Polygon,MultiPolygon

* GeometryCollection

* Feature,FeatureCollection

* Circle

and [H3 hexagon indexes](https://h3geo.org), 

using:

    [H3-GO](https://github.com/uber/h3-go) and

    [GeoJSON](https://github.com/tidwall/geojson)

## Installation

```shell

$ go get github.com/mmadfox/go-geojson2h3

```

## API

```go

// ToH3 converts a GeoJSON objects to a list of hexagons with specified resolution.

ToH3(resolution int, o geojson.Object) (indexes []h3.H3Index, err error)

// ToFeatureCollection converts a set of hexagons to a GeoJSON `FeatureCollection`

// with the set outline(s). The feature's geometry type will be `Polygon`.

ToFeatureCollection(indexes []h3.H3Index) (*geojson.FeatureCollection, error)

```

## Examples

* [Point, MultiPoint](examples/point.go)

* [LineString, MultiLineString](examples/line.go)

* [Polygon,MultiPolygon](examples/polygon.go)

* [GeometryCollection](examples/collection.go)

* [Feature,FeatureCollection](examples/feature.go)

* [Circle](examples/circle.go)

* [Rect](examples/rect.go)

```go

package main

import (

	"fmt"

	"github.com/mmadfox/go-geojson2h3"

	"github.com/tidwall/geojson"

	"github.com/uber/h3-go/v3"

)

func main() {

	resolution := 9

	object, err := geojson.Parse(`{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"shape":"Polygon","name":"Unnamed Layer","category":"default"},"geometry":{"type":"Polygon","coordinates":[[[-73.901303,40.756892],[-73.893924,40.743755],[-73.871476,40.756278],[-73.863378,40.764175],[-73.871444,40.768467],[-73.879852,40.760014],[-73.885515,40.764045],[-73.891522,40.761054],[-73.901303,40.756892]]]},"id":"a6ca1b7e-9ddf-4425-ad07-8a895f7d6ccf"}]}`, nil)

	if err != nil {

		panic(err)

	}

	indexes, err := geojson2h3.ToH3(resolution, object)

	if err != nil {

		panic(err)

	}

	for _, index := range indexes {

		fmt.Printf("h3index: %s\n", h3.ToString(index))

	}

	featureCollection, err := geojson2h3.ToFeatureCollection(indexes)

	if err != nil {

		panic(err)

	}

	fmt.Println("Polyfill:")

	fmt.Println(featureCollection.JSON())

}

```

## Contributing

Pull requests and [Github issues](https://github.com/mmadfox/go-geojson2h3/issues) are welcome. Please include tests for new work, and keep the library test coverage at 90-100%.