h3_dart

Description:

h3 dart

H3 Dart #
If you're developing Flutter application, use should use h3_flutter instead.
The package allows to use Uber's H3 library directly in your Dart application
The package uses h3_ffi and h3_web under the hood.
final h3Factory = const H3Factory();
const kIsWeb = identical(0, 0.0); // taken from https://api.flutter.dev/flutter/foundation/kIsWeb-constant.html
final h3 = kIsWeb
? h3Factory.web()
: h3Factory.byPath('path/to/library.dll');
// Get hexagons in specified triangle.
final hexagons = h3.polyfill(
resolution: 5,
coordinates: [
GeoCoord(20.4522, 54.7104),
GeoCoord(37.6173, 55.7558),
GeoCoord(39.7015, 47.2357),
],
);
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There are also few methods ported from JS library Geojson2H3, to access them you should instantiate Geojson2H3 class using const Geojson2H3(h3). It uses package:geojson2h3 internally.
Setup #
If you're developing Flutter application, use should use h3_flutter instead.
VM #
Get compiled h3 c library, depending on your platform it may have extension .so, .dll or any.


You can run scripts/build_h3.sh script, the compiled library will be at h3_ffi/c/h3lib/build/h3.so


You can compile it by yourself using C-code placed in c folder in this repository. It has small changes comparing to original Uber's code to make it more compatible with iOS and macOS versions of h3_flutter. This code is recompiled and used for testing everytime tests are launched, so it should work well.


You can compile original Uber's code, which also should work well, just make sure you use correct version - https://github.com/uber/h3


Place your library somewhere and load it using final h3 = const H3Factory().byPath('path/to/library.dll');
Web #
Web version is built on top of h3-js, you have to import it.
Add next line to your index.html:
<script defer src="https://unpkg.com/[email protected]"></script>
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Note, main.dart.js import should go after this line
You can load the web version using final h3 = const H3Factory().web();