marchdev-tk/google_polyline_algorithm

google_polyline_algorithm

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Dart implementation of Googles Polyline Encoding lossy compression Algorithm.

Getting Started

This package adds following methods to work with Googles Polyline Encoding Algorithm:

• encodePoint(num current, {num previous = 0, int accuracyExponent = 5}) encodes a single coordinate

• encodePolyline(List<List<num>> coordinates, {int accuracyExponent = 5}) encodes a list of coordinates into an encoded polyline stirng

• decodePolyline(String polyline, {int accuracyExponent = 5}) decodes an encoded polyline string into a list of coordinates

Examples

import 'package:google_polyline_algorithm/google_polyline_algorithm.dart';

final coord = encodePoint(-179.9832104);
print(coord);
// output is `~oia@'

final coords = encodePolyline([
  [38.5, -120.2],
  [40.7, -120.95],
  [43.252, -126.453],
]);
print(coords);
// output is `_p~iF~ps|U_ulLnnqC_mqNvxq`@'

final polyline = decodePolyline('_p~iF~ps|U_ulLnnqC_mqNvxq`@');
print(polyline);
// output is [[38.5, -120.2],[40.7, -120.95],[43.252, -126.453],]