| .github/workflows | ||
| .wiki | ||
| lib | ||
| test | ||
| .gitignore | ||
| analysis_options.yaml | ||
| CHANGELOG.md | ||
| LICENSE | ||
| pubspec.yaml | ||
| README.md | ||
qibla
Qibla direction, great-circle path, and haversine distance for Dart and Flutter. Pure math, zero dependencies.
Installation
dependencies:
qibla: ^1.0.0
Quick Start
import 'package:qibla/qibla.dart';
// Bearing from New York to the Ka'bah
final bearing = qiblaAngle(40.7128, -74.006);
print(bearing); // ~58.48
print(compassDir(bearing)); // NE
// Distance in kilometers
final km = distanceKm(40.7128, -74.006, kaabaLat, kaabaLng);
print(km); // ~9634
API
qiblaAngle(lat, lng)
Computes the initial bearing (forward azimuth) from the given coordinates to the Ka'bah.
| Parameter | Type | Description |
|---|---|---|
lat |
double |
Latitude in decimal degrees (-90 to 90) |
lng |
double |
Longitude in decimal degrees (-180 to 180) |
| Returns | double |
Bearing in degrees clockwise from north (0-360) |
Throws RangeError if coordinates are out of bounds.
compassDir(bearing)
Eight-point compass abbreviation: N, NE, E, SE, S, SW, W, NW.
compassName(bearing)
Full compass name: North, Northeast, East, Southeast, South, Southwest, West, Northwest.
qiblaGreatCircle(lat, lng, [steps])
Generates waypoints along the great circle from (lat, lng) to the Ka'bah using spherical linear interpolation (Slerp). Returns steps + 1 points (default: 121).
Useful for drawing Qibla direction lines on maps.
distanceKm(lat1, lng1, lat2, lng2)
Haversine distance between two points in kilometers (spherical Earth approximation, R = 6,371 km).
Constants
| Name | Value | Description |
|---|---|---|
kaabaLat |
21.422511 | Ka'bah center latitude (degrees north) |
kaabaLng |
39.826150 | Ka'bah center longitude (degrees east) |
earthRadiusKm |
6371 | WGS-84 volumetric mean radius |
Architecture
All calculations use the forward azimuth formula from spherical trigonometry. Great-circle paths use spherical linear interpolation (Slerp). Distance uses the haversine formula. The Ka'bah coordinates are fixed constants verified against published GPS surveys.
Compatibility
Dart 3.7+. Works with Flutter and standalone Dart applications.
Related
Acknowledgments
Ka'bah coordinates verified against published GPS surveys and cross-checked with satellite imagery. Spherical trigonometry formulas follow the standard forward azimuth derivation used in aviation and geodesy.