# geodesy

A Dart library for implementing geodesic and trigonometric calculations based on a spherical Earth model for working with points and paths such as distances, bearings and destinations

## Getting Started

### Add the following line in your pubspec file

``````geodesy:
``````

### Include the widget in your dart file

``````import 'package:geodesy/geodesy.dart';
``````

## Usage

### Geodesy()

``````Geodesy geodesy = Geodesy();
``````

### LatLng(double latitude, double longitude)

``````LatLng l = LatLng(22.308, 114.1716);
``````

## Methods

### destinationPointByDistanceAndBearing(LatLng l, num distance, num bearing, num radius)

Calculate a destination point given the distance and bearing. If raduis is not specified, Earth radius will be used.

``````LatLng distinationPoint = geodesy.destinationPointByDistanceAndBearing(l3, 2400, 420.2, null);
``````

### midPointBetweenTwoGeoPoints(LatLng l1, LatLng l2)

Calcuate the midpoint bewteen teo geo points.

``````LatLng midpoint = geodesy.midPointBetweenTwoGeoPoints(l1, l2);
``````

### distanceBetweenTwoGeoPoints(LatLng l1, LatLng l2, num radius)

Calculate the distance in meters between two geo points. If raduis is not specified, Earth radius will be used.

``````num distance = geodesy.distanceBetweenTwoGeoPoints(l1, l2, null);
``````

### bearingBetweenTwoGeoPoints(LatLng l1, LatLng l2)

Calculate the bearing from point l1 to point l2.

``````num finalBearing = geodesy.finalBearingBetweenTwoGeoPoints(l1, l2);
``````

### finalBearingBetweenTwoGeoPoints(LatLng l1, LatLng l2)

Calculate the final bearing from point l1 to point l2.

``````num finalBearing = geodesy.finalBearingBetweenTwoGeoPoints(l1, l2);
``````

Convert degrees to radians

``````num l1LatRadians = degreesToRadians(l1.lat);
``````

Convert degrees to radians

``````num degrees = radiansToDegrees(latRadians);
``````

### isGeoPointInBoudingBox(LatLng l, LatLng topLeft, LatLng bottomRight)

Check if a given geo point is in the bouding box

``````bool inBoudingBox = geodesy.isGeoPointInBoudingBox(l1, l2, l3);
``````

### intersectionByPaths(LatLng l1, LatLng l2, num b1, num b2)

Calculate the geo point of intersection of two given paths

``````LatLng intersectionByPaths = geodesy.intersectionByPaths(l1, l2, b1, b2);
``````

### crossTrackDistanceTo(LatLng l1, LatLng start, LatLng end, num radius)

Calculate signed distance from a geo point to greate circle with start and end points

``````num distanceToGreatCircle = geodesy.crossTrackDistanceTo(l1, l2, l3, null);
``````

### isGeoPointInPolygon(LatLng l, List polygon)

Check if a given geo point is in the a polygon using even-odd rule algorithm

``````bool isGeoPointInPolygon = geodesy.isGeoPointInPolygon(l, poly);
``````

geodesy