gmaps_by_road_distance_calculator 3.0.2

This is a Package to calculate the by-road distance from one point to another in map.

Quick Start 🚀

Basic Usage

import 'package:road_distance_calculator/road_distance_calculator.dart';

final calculator = ByRoadDistanceCalculator();
final points = [
  LatLng(37.7749, -122.4194),  // SF
  LatLng(34.0522, -118.2437)   // LA
];

final distance = calculator.calculateDistance(points);
print('Distance: \${distance.toStringAsFixed(2)} km');  // Output: Distance: 559.23 km

API Reference 📚

Core Methods

calculateDistance(List<LatLng> points) → double

Calculates total distance for a list of coordinates.

Parameters:

• points: Ordered list of LatLng coordinates.

Returns:

• Total distance in kilometers.

Polyline Decoding

static decodePolylineString(String encoded) → List<LatLng>

Decodes polyline strings (e.g., "yxocFxfgy@...") into coordinates.

final polyline = 'yxocFxfgy@...';
final points = ByRoadDistanceCalculator.decodePolylineString(polyline);

GPS File Parsing

parseGPX(String gpxContent) → List<LatLng>

Extracts coordinates from GPX files.

final gpxFile = File('route.gpx').readAsStringSync();
final points = calculator.parseGPX(gpxFile);

parseKML(String kmlContent) → List<LatLng>

Extracts coordinates from KML files.

final kmlFile = File('route.kml').readAsStringSync();
final points = calculator.parseKML(kmlFile);

Real-Time Tracking

addPoint(LatLng point)

Adds points incrementally for live tracking.

distanceUpdates → Stream<double>

Stream of cumulative distance updates.

calculator.distanceUpdates.listen((km) {
  print('Distance updated: \${km.toStringAsFixed(2)} km');
});

// Simulate GPS updates
await Future.delayed(Duration(seconds: 1));
calculator.addPoint(LatLng(37.3354, -122.0097));

Use Cases 💡

1. Fitness Apps 🏃‍♂️

Track running/cycling routes from GPX files:

final gpxPoints = calculator.parseGPX(gpxData);
final distance = calculator.calculateDistance(gpxPoints);

2. Logistics Solutions 🚚

Calculate delivery route distances:

final routePoints = ByRoadDistanceCalculator.decodePolylineString(logisticsPolyline);
print('Total route: \${calculator.calculateDistance(routePoints)} km');

3. Travel Planning ✈️

Estimate road trip distances:

final tripPlan = [start, stop1, stop2, destination];
print('Total trip: \${calculator.calculateDistance(tripPlan)} km');

4. IoT Tracking Devices 📡

Live tracking integration:

void onGpsUpdate(LatLng position) {
  calculator.addPoint(position);
  // Stream updates automatically
}

Contributing 🤝

1. Fork the repository.
2. Create your feature branch.
3. Add tests for new features.
4. Submit a pull request.

License 📄

MIT License - See LICENSE for details.

Credits

Geospatial calculations powered by latlong2.