Height Map

A modern Flutter application that displays altitude information from multiple sensors and allows exploring elevations on an interactive world map.

NOTICE

Yep, this is AI generated (Claude Opus 4.5). For such a simple app, was the simplest way. So, keep this in mind, this app might have bugs, i just tested it once by myself, but it seems to work.

Features

🏔️ Multi-Sensor Altitude Display

• GPS Altitude: Satellite-based elevation reading
• Barometer: Atmospheric pressure-based altitude (where hardware is available)
• Elevation API: Terrain elevation data from Open Topo Data

🗺️ Interactive World Map

• OpenStreetMap-based tile rendering
• Real-time location tracking
• Tap anywhere to see elevation at that point
• Elevation comparison showing height difference from your current position

📊 Detailed Sensor Information

• Individual sensor readings with accuracy indicators
• Reliability status for each data source
• Conversion between meters and feet
• Last update timestamps

Screenshots

Map View	Height Details	Elevation Comparison
Main map with location marker	All sensor readings	Selected point info

Architecture

This app follows a clean architecture pattern with clear separation of concerns:

lib/
├── core/                    # Core utilities and configuration
│   ├── constants/           # App-wide constants
│   ├── di/                  # Dependency injection (GetIt)
│   ├── extensions/          # Dart extensions
│   ├── router/              # Navigation (go_router)
│   ├── theme/               # App theming
│   └── utils/               # Utilities (Result, Failure)
├── data/                    # Data layer
│   ├── datasources/         # Data sources (sensors, API)
│   ├── models/              # Data models
│   └── repositories/        # Repository implementations
└── presentation/            # Presentation layer
    ├── blocs/               # BLoC state management
    │   ├── height/          # Height/altitude BLoC
    │   ├── location/        # Location tracking BLoC
    │   └── map/             # Map interactions BLoC
    ├── pages/               # App screens
    └── widgets/             # Reusable widgets

Dependencies

State Management & Architecture

• flutter_bloc - State management using BLoC pattern
• equatable - Value equality for states and events
• get_it - Dependency injection
• dartz - Functional programming utilities

Navigation

• go_router - Declarative routing

Maps & Location

• flutter_map - OpenStreetMap-based map widget
• latlong2 - Geographical coordinates
• geolocator - GPS location services

Sensors

• sensors_plus - Access to device sensors (barometer)

Networking

• dio - HTTP client for elevation API

UI

• flutter_animate - Smooth animations
• google_fonts - Typography

Getting Started

Prerequisites

• Flutter SDK 3.35.4 or later
• Dart SDK 3.9.2 or later
• Android Studio / VS Code with Flutter extensions
• Physical device recommended (for sensor access)

Installation

1. Clone the repository:

   git clone https://github.com/yourusername/height_map.git
   cd height_map

2. Install dependencies:

   flutter pub get

3. Run the app:

   flutter run

Building for Production

Android

flutter build apk --release
# or for app bundle
flutter build appbundle --release

iOS

flutter build ios --release

Configuration

Elevation API

The app uses Open Topo Data for elevation queries. The free API provides:

• SRTM 90m resolution worldwide coverage
• Up to 100 points per request
• Rate limiting applies for public API

For production use, consider hosting your own Open Topo Data instance.

Permissions

Android

• ACCESS_FINE_LOCATION - GPS access
• ACCESS_COARSE_LOCATION - Network-based location
• INTERNET - Elevation API access

iOS

• NSLocationWhenInUseUsageDescription - Location access while using app
• NSLocationAlwaysAndWhenInUseUsageDescription - Background location (optional)

Usage

Main Screen

1. Grant location permission when prompted
2. Your current location appears on the map with a blue marker
3. Current altitude is shown in the top-right corner
4. Tap the altitude indicator to see detailed sensor readings

Exploring Elevations

1. Tap anywhere on the map to place a marker
2. The elevation at that point will be fetched
3. A card shows the elevation and difference from your position
4. Tap the X to clear the selection

Height Details Page

• View all available sensor readings
• See accuracy and reliability information
• Understand how each sensor works

API Reference

BLoCs

HeightBloc

Manages altitude data from all sensors.

Events:

• StartHeightMonitoring - Begin sensor monitoring
• StopHeightMonitoring - Stop sensor monitoring
• FetchApiElevation - Fetch elevation for a position

States:

• HeightInitial - Initial state
• HeightLoading - Loading sensor data
• HeightLoaded - Data available with all measurements
• HeightError - Error state

LocationBloc

Manages GPS location tracking.

Events:

• StartLocationTracking - Begin location updates
• StopLocationTracking - Stop location updates
• GetCurrentLocation - Get location once

States:

• LocationInitial - Initial state
• LocationLoading - Fetching location
• LocationLoaded - Location available
• LocationPermissionDenied - Permission not granted
• LocationServiceDisabled - GPS disabled

MapBloc

Manages map interactions and elevation comparisons.

Events:

• MapTapped - User tapped on map
• ClearSelectedPoint - Clear selection
• UpdateUserPosition - Update user location on map

States:

• MapInitial - Initial state
• MapReady - Map ready with optional selected point

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Open Topo Data for elevation data
• OpenStreetMap for map tiles
• Flutter team for the amazing framework