---

What is geo_fence_utils?

geo_fence_utils is a comprehensive Flutter/Dart package designed for handling geofence calculations and location-based operations.

It provides utilities for:

• Calculating distances between geographic points
• Detecting whether points lie within circular or polygonal boundaries
• Performing batch operations on multiple locations efficiently

This package is ideal for developers building location-aware applications without dealing with complex geographic calculations.

---

📸 Screenshots

Circle Geofence	Polygon Geofence	Custom Markers

---

🎯 Purpose

The primary purpose of this package is to simplify geospatial calculations in Flutter and Dart applications.

It handles complex geographic math so you can focus on building your application logic.

---

🚀 Common Use Cases

• Delivery & Logistics – Determine if delivery addresses fall within service areas
• Location-Based Notifications – Trigger alerts when users enter or exit zones
• Asset Tracking – Monitor vehicles or equipment within boundaries
• Gaming – Create location-based game zones
• Security Systems – Detect devices leaving authorized areas
• Attendance Systems – Check if users are inside allowed locations
• Ride Sharing – Match drivers with passengers within radius
• Marketing – Send location-based promotions

---

✨ Key Features

Feature	Description
📏 Accurate Distance Calculation	Uses Haversine formula (~0.5% accuracy)
🔵 Circle Geofence	Efficient point-in-circle detection
🔺 Polygon Geofence	Ray casting algorithm for complex shapes
⚡ Batch Operations	Process many points efficiently
🗺 Map Widgets	Works with Flutter Map and Google Maps
📍 Custom Markers	Support PNG and SVG markers
🌍 Cross Platform	Works on iOS, Android, Web, Desktop
🧪 Well Tested	266 tests with 96% coverage
🧩 Pure Dart	No native dependencies
🔒 Type Safe	Full null safety support

---

📦 Installation

Add the package to your pubspec.yaml:

dependencies:
  geo_fence_utils: ^2.1.0

Then run:

flutter pub get

Or use Flutter CLI:

flutter pub add geo_fence_utils

---

📚 Documentation

Full usage examples are available in the example app.

➡ See example usage here:

example/README.md

The example demonstrates:

• Creating geofence circles
• Creating polygon boundaries
• Drawing polylines
• Adding custom markers
• Displaying geofences on maps
• Running geofence detection logic

---

🧩 Package Overview

Core Models

The package provides three main data models:

• GeoPoint – Represents a geographic coordinate
• GeoCircle – Circular geofence with center and radius
• GeoPolygon – Polygon geofence with multiple vertices

---

Services

Three main service classes handle operations:

• GeoDistanceService

  • Calculate distance between points
  • Find closest or farthest point

• GeoCircleService

  • Check points inside circles
  • Detect circle overlap

• GeoPolygonService

  • Point inside polygon
  • Polygon area and perimeter

---

Map Widgets

Interactive widgets for visualizing geofences:

• GeoGeofenceMap – Main map widget
• GeoCircleWidget – Circular geofence display
• GeoPolygonWidget – Polygon geofence display
• GeoPolylineWidget – Route and path display
• GeoMarkerWidget – Custom markers (PNG/SVG)

---

⚙ Technical Details

• Coordinate System: WGS 84 (GPS standard)

• Distance Formula: Haversine

• Distance Units: Meters

• Supported Platforms:

  • iOS
  • Android
  • Web
  • Windows
  • macOS
  • Linux

---

⚡ Performance

Operation	Time Complexity	Notes
Distance calculation	O(1)	Constant time
Circle containment	O(1)	Constant time
Polygon containment	O(n)	Linear with vertices
Batch filtering	O(n×m)	n points, m vertices

---

📚 Documentation & Resources

• API Docs: https://pub.flutter-io.cn/packages/geo_fence_utils
• Test Coverage: TEST_COVERAGE.md
• Example App: /example directory
• Issues: https://github.com/MEET-1008/geo_fence_utils/issues
• Discussions: https://github.com/MEET-1008/geo_fence_utils/discussions

---

🧪 Testing

Run tests:

flutter test

Generate coverage report:

flutter test --coverage
genhtml coverage/lcov.info -o coverage/html

---

🤝 Contributing

Contributions are welcome.

Please ensure:

• All tests pass
• Code follows Dart style guidelines
• New features include tests
• Documentation updated

Steps:

1. Fork repository
2. Create feature branch
3. Commit changes
4. Push branch
5. Open Pull Request

---

📄 License

This project is licensed under the MIT License.

See the LICENSE file for details.

---