LatLng Tilr x y z point

latlong_extension.dart

import 'package:latlong/latlong.dart';
import 'dart:math' as math;

extension LatLngExtension on LatLng {
  Map<String, double> toPoint() {
    var siny = math.min(
      math.max(math.sin(this.latitude * (math.pi / 180)), -.9999),
      .9999,
    );
    return {
      'x': 128 + this.longitude * (256 / 360),
      'y': 128 +
          0.5 * math.log((1 + siny) / (1 - siny)) * -(256 / (2 * math.pi)),
    };
  }

  Map<String, num> toTile(double zoom) {
    final t = math.pow(2, zoom);
    final s = 256 / t;
    final p = this.toPoint();
    return {'x': (p['x'] / s).floor(), 'y': (p['y'] / s).floor(), 'z': zoom};
  }
}