coordinates2country
What country is at a particular latitude/longitude? This Java library tells you in 100 milliseconds, without using the Internet and without requiring any permission.
- Fast reverse geocoding
- Never needs an Internet connection
For the Android version, see https://github.com/coordinates2country/coordinates2country-android.
Use
This sample program that uses the library might help.
1) Import the library
If using Gradle:
implementation("io.github.coordinates2country:coordinates2country:1.4")
For other build systems or for the JAR, search for the latest version on Maven Central.
At the top of your Java file, after the package declaration, insert this line:
import io.github.coordinates2country.Coordinates2Country;
2) Call the library
Coordinates2Country.country(-23.7, 39.8) returns the String France.
If you prefer identifiers, Coordinates2Country.countryQID(-23.7, 39.8) returns 142, the Wikidata QID number of France.
Build
Run ./gradlew build, or ./build.sh if you modified anything in the data folder.
Generate the gray map
- Open countries.xcf in Gimp
- Image > Duplicate
- Colors > Components > Extract component > RGB Red
- File > Export As
- Filename: data/countries-8bitgray.png
- Export > 8bpc GRAY
When modifying the map, you can modify colors to see better, as long as you keep the RGB red component.
Info
Source image: https://commons.wikimedia.org/wiki/File:Internationalwaters.png Kvasir Creative Commons Attribution-Share Alike 3.0 Unported, 2.5 Generic, 2.0 Generic and 1.0 Generic license.
Projection: https://en.wikipedia.org/wiki/Equirectangular_projection with phi0=0 and lambda0=0
Useful maps: https://farm8.staticflickr.com/7292/10134658063_fca4fc3da2_o.jpg https://i.imgur.com/lzm0fWN.png