to check if the retrieved points are inside polygon

[MusaMsigwa]

I started by checking if the point is inside polygon and it worked well. my goal is to allow a user to draw a polygon then to use that list to check if there is any point that is inside drawn polygon. I archeved to allow user draw the polygon now I want to check if there is any point inside that polygon.

the list of latLang that make the polygon is List<LatLng> _userPolyLinesLatLngList = [];

i want to create new list that i can use for map tool kit that List should have LatLang from above list.

Help me to convert that List so as I can assign as List of latlang for toolkit. therefore what I want is two variable of List the above List and new List that i can use on toolkit to check if the point is inside the polygon.

         ` //something like this
          List<LatLng> _userPolyLinesLatLngList = [];
          List<mp.LatLng> newListForToolKit = _userPolyLinesLatLngList;
          //this brings error` //then 
          final points = mp.PolygonUtil.containsLocation(
              mp.LatLng(-6.7924, 39.2083), newListForToolKit, true);

              `

And Here are the complete code that allow user to draw polygon. I want to check if the point is inside polygon. `import 'dart:async'; import 'dart:collection'; import 'dart:convert'; import 'dart:io'; import 'dart:math' as Math;

import 'package:flutter/material.dart'; import 'package:geocoding/geocoding.dart'; import 'package:google_maps_flutter/google_maps_flutter.dart'; import 'package:maps_toolkit/maps_toolkit.dart' as mp;

class MyHomePageMap extends StatefulWidget { MyHomePageMap({Key? key}) : super(key: key);

@override _MyHomePageMapState createState() => _MyHomePageMapState(); }

class _MyHomePageMapState extends State { static final Completer _controller = Completer();

static final CameraPosition _kGooglePlex = CameraPosition( target: LatLng(37.42796133580664, -122.085749655962), zoom: 14.4746, );

final Set _polygons = HashSet(); final Set _polyLines = HashSet();

bool _drawPolygonEnabled = false; List _userPolyLinesLatLngList = []; // List _userPolyLinesLatLngListsUser = [];

final pointFromGoogleMap = LatLng(90, 0);

bool _clearDrawing = false; int? _lastXCoordinate, _lastYCoordinate;

var distanceBetweenPoints = mp.SphericalUtil.computeDistanceBetween( mp.LatLng(51.5073509, -0.1277583), mp.LatLng(48.856614, 2.3522219));

final cityLondon = mp.LatLng(51.5073509, -0.1277583); final cityParis = mp.LatLng(48.856614, 2.3522219);

final distance = mp.SphericalUtil.computeDistanceBetween( mp.LatLng(51.5073509, -0.1277583), mp.LatLng(48.856614, 2.3522219)) / 1000.0; // List polygony = [ // (37.43296265331129, -122.08832357078792), // (37.43006265331129, -122.08832357078792), // (37.43006265331129, -122.08332357078792),

// ];

// print('Distance between London and Paris is $distance km.'); // PolygonUtil.containsLocation - computes whether the given point lies inside the specified polygon. // final distances = mp.SphericalUtil.computeDistanceBetween(mp.LatLng(51.5073509, -0.1277583), 4.3)

List polygonCoord = [ mp.LatLng(37.43296265331129, -122.08832357078792), mp.LatLng(37.43006265331129, -122.08832357078792), mp.LatLng(37.43006265331129, -122.08332357078792), mp.LatLng(37.43296265331129, -122.08832357078792) ];

@override Widget build(BuildContext context) { return Scaffold( body: GestureDetector( onPanUpdate: (_drawPolygonEnabled) ? _onPanUpdate : null, onPanEnd: (_drawPolygonEnabled) ? _onPanEnd : null, child: GoogleMap( mapType: MapType.normal, initialCameraPosition: _kGooglePlex, polygons: _polygons, polylines: _polyLines, onMapCreated: (GoogleMapController controller) { _controller.complete(controller); }, ), ), floatingActionButton: Column( mainAxisAlignment: MainAxisAlignment.end, children: [ FloatingActionButton( onPressed: () { print("The DISTANCE IS $distance"); final points = mp.PolygonUtil.containsLocation( mp.LatLng(-6.7924, 39.2083), polygonCoord, true); print("The POIT IS FOUND ON THE FOLLOWING $points"); // final a = mp._userPolyLinesLatLngList; // print("The POIT IS FOUND ON THE FOLLOWING $a YES");

          List<mp.LatLng> polygonCoords = [
            mp.LatLng(37.43296265331129, -122.08832357078792),
            mp.LatLng(37.43006265331129, -122.08832357078792),
            mp.LatLng(37.43006265331129, -122.08332357078792),
            mp.LatLng(37.43296265331129, -122.08832357078792)
          ];
          List<LatLng> _userPolyLinesLatLngList = [];
          // ignore: unused_local_variable
          double a, b;

          // var b;
          // var lat;
          // List<mp.LatLng> _userPolyLinesLatLngListsUser =
          //     _userPolyLinesLatLngList;

          final pointFromGoogleMap = LatLng(90, 0);
          final pointMp = mp.LatLng(
              pointFromGoogleMap.latitude, pointFromGoogleMap.longitude);

          print("The POIT IS FOUND ON THE FOLLOWING $points YES");
          if (points == true) {
            print("The POIT IS FOUND ON THE FOLLOWING $points YES");
          } else {
            print("The POIT IS FOUND ON THE FOLLOWING $points No");
          }
        },
        tooltip: 'Drawing',
        child: Icon(Icons.menu),
      ),
      FloatingActionButton(
        onPressed: _toggleDrawing,
        tooltip: 'Drawing',
        child: Icon((_drawPolygonEnabled) ? Icons.cancel : Icons.edit),
      ),
    ],
  ),
);

}

_toggleDrawing() { _clearPolygons(); setState(() => _drawPolygonEnabled = !_drawPolygonEnabled); }

_onPanUpdate(DragUpdateDetails details) async { // To start draw new polygon every time. if (_clearDrawing) { _clearDrawing = false; _clearPolygons(); }

if (_drawPolygonEnabled) {
  double? x, y;
  if (Platform.isAndroid) {
    // It times in 3 without any meaning,
    // We think it's an issue with GoogleMaps package.
    x = details.globalPosition.dx * 3;
    y = details.globalPosition.dy * 3;
  } else if (Platform.isIOS) {
    x = details.globalPosition.dx;
    y = details.globalPosition.dy;
  }

  // Round the x and y.
  int xCoordinate = x!.round();
  int yCoordinate = y!.round();

  // Check if the distance between last point is not too far.
  // to prevent two fingers drawing.
  if (_lastXCoordinate != null && _lastYCoordinate != null) {
    var distance = Math.sqrt(Math.pow(xCoordinate - _lastXCoordinate!, 2) +
        Math.pow(yCoordinate - _lastYCoordinate!, 2));
    // Check if the distance of point and point is large.
    if (distance > 80.0) return;
  }

  // Cached the coordinate.
  _lastXCoordinate = xCoordinate;
  _lastYCoordinate = yCoordinate;

  ScreenCoordinate screenCoordinate =
      ScreenCoordinate(x: xCoordinate, y: yCoordinate);

  final GoogleMapController controller = await _controller.future;
  LatLng latLng = await controller.getLatLng(screenCoordinate);
  // mp.LatLng latLngs = await controller.getLatLng(screenCoordinate);
  try {
    // Add new point to list.
    _userPolyLinesLatLngList.add(latLng);
    // _userPolyLinesLatLngListsUser.add(latLngs);

    _polyLines.removeWhere(
        (polyline) => polyline.polylineId.value == 'user_polyline');
    _polyLines.add(
      Polyline(
        polylineId: PolylineId('user_polyline'),
        points: _userPolyLinesLatLngList,
        width: 2,
        color: Colors.blue,
      ),
    );
  } catch (e) {
    print(" error painting $e");
  }
  setState(() {});
}

}

// Yes, you cannot use Google Maps LatLng directly. You should convert Google Maps LatLng into Maps Toolkit LatLng, for ex.:

// import 'package:maps_toolkit/maps_toolkit.dart' as mp; // import 'package:google_maps/google_maps.dart'; // import 'package:test/test.dart';

// void main() { // final pointFromGoogleMap = LatLng(90, 0); // final pointMp = mp.LatLng(pointFromGoogleMap.lat, pointFromGoogleMap.lng);

// bool result = mp.PolygonUtil.containsLocation(pointMp, TOTAL_COVERAGE, false); // }

_onPanEnd(DragEndDetails details) async { // Reset last cached coordinate _lastXCoordinate = null; _lastYCoordinate = null;

if (_drawPolygonEnabled) {
  _polygons
      .removeWhere((polygon) => polygon.polygonId.value == 'user_polygon');
  _polygons.add(
    Polygon(
      polygonId: PolygonId('user_polygon'),
      points: _userPolyLinesLatLngList,
      strokeWidth: 2,
      strokeColor: Colors.blue,
      fillColor: Colors.blue.withOpacity(0.4),
    ),
  );
  setState(() {
    _clearDrawing = true;
  });
}

}

_clearPolygons() { setState(() { _polyLines.clear(); _polygons.clear(); _userPolyLinesLatLngList.clear(); }); } } `