jifalops / dart-latlong

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This is a fork of https://github.com/MikeMitterer/dart-latlong. The goal is to keep it up to date with Dart language changes.

LatLong provides a lightweight library for common latitude and longitude calculation.

This library supports both, the "Haversine" and the "Vincenty" algorithm.

"Haversine" is a bit faster but "Vincenty" is far more accurate!

LatLong

Catmull-Rom algorithm is used for smoothing out the path.

Basic usage

Distance

    final Distance distance = new Distance();

    // km = 423
    final int km = distance.as(LengthUnit.Kilometer,
     new LatLng(52.518611,13.408056),new LatLng(51.519475,7.46694444));

    // meter = 422591.551
    final int meter = distance(
        new LatLng(52.518611,13.408056),
        new LatLng(51.519475,7.46694444)
        );

Offset

    final Distance distance = const Distance();
    final num distanceInMeter = (earthRadius * math.pi / 4).round();

    final p1 = new LatLng(0.0, 0.0);
    final p2 = distance.offset(p1, distanceInMeter, 180);

    // LatLng(latitude:-45.219848, longitude:0.0)
    print(p2.round());

    // 45° 13' 11.45" S, 0° 0' 0.00" O
    print(p2.toSexagesimal());

Path smoothing

    // zigzag is a list of coordinates
    final Path path = new Path.from(zigzag);

    // Result is below
    final Path steps = path.equalize(8,smoothPath: true);

Smooth path

Features and bugs

Please file feature requests and bugs at the issue tracker.

License

Copyright 2015 Michael Mitterer (office@mikemitterer.at),
IT-Consulting and Development Limited, Austrian Branch

Licensed 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

   https://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.

If this plugin is helpful for you - please (Circle) me or star this repo here on GitHub