Skip to content

Latest commit

 

History

History
126 lines (85 loc) · 4.28 KB

README.md

File metadata and controls

126 lines (85 loc) · 4.28 KB
Raw

GeoDesk is a fast and storage-efficient geospatial database for OpenStreetMap data. Also available for Python.

Why GeoDesk?

  • Small storage footprint — GeoDesk's GOL files are only 20% to 50% larger than the original OSM data in PBF format — that's less than a tenth of the storage consumed by a traditional SQL-based database.

  • Fast queries — typically 50 times faster than SQL.

  • Fast to get started — Converting .osm.pbf data to a GOL is 20 times faster than an import into an SQL database. Alternatively, download pre-made data tiles for just the regions you need and automatically assemble them into a GOL.

  • Intuitive API — No need for object-relational mapping; GeoDesk queries return Node, Way and Relation objects. Quickly discover tags, way-nodes and relation members. Get a feature's Geometry, measure its length/area.

  • Proper handling of relations — (Traditional geospatial databases deal with geometric shapes and require workarounds to support this unique and powerful aspect of OSM data.)

  • Seamless integration with the Java Topology Suite (JTS) for advanced geometric operations, such as buffer, union, simplify, convex and concave hulls, Voronoi diagrams, and much more.

  • Modest hardware requirements — If it can run a 64-bit JVM, it'll run GeoDesk.

Get Started

Maven

Include this dependency in your project's pom.xml:

<dependency>
    <groupId>com.geodesk</groupId>
    <artifactId>geodesk</artifactId>
    <version>0.2.0</version>
</dependency>

Alternatively, to build the latest version from source:

git clone https://github.com/clarisma/geodesk.git
cd geodesk
mvn install

If you get weird exceptions during mvn install, you should upgrade Maven to version 3.8.5 or above.

Example Application

import com.geodesk.feature.*;
import com.geodesk.util.*;

public class PubsExample
{
    public static void main(String[] args)
    {
        FeatureLibrary library = new FeatureLibrary(     // 1    
            "example.gol",                               // 2
            "https://data.geodesk.com/switzerland");     // 3
        
        for(Feature pub: library                         // 4
            .select("na[amenity=pub]")                   // 5
            .in(Box.ofWSEN(8.53,47.36,8.55,47.38)))      // 6
        {
            System.out.println(pub.stringValue("name")); // 7
        }
        
        library.close();                                 // 8
    }
}

What's going on here?

  1. We're opening a feature library ...

  2. ... with the file name example.gol (If it doesn't exist, a blank one is created)

  3. ... and a URL from which data tiles will be downloaded.

  4. We iterate through all the features ...

  5. ... that are pubs (GeoDesk query language — similar to MapCSS)

  6. ... in downtown Zurich (bounding box with West/South/East/North coordinates).

  7. We print the name of each pub.

  8. We close the library.

That's it, you've created your first GeoDesk application!

More Examples

Find all movie theaters within 500 meters from a given point:

Features movieTheaters = library
    .select("na[amenity=cinema]")
    .maxMetersFromLonLat(500, myLon, myLat);

Remember, OSM uses British English for its terminology.

Discover the bus routes that traverse a given street:

for(Feature route: street.parents("[route=bus]"))
{
    System.out.format("- %s from %s to %s",
        route.stringValue("ref"),
        route.stringValue("from"),
        route.stringValue("To"));
}

Count the number of entrances of a building:

int numberOfEntrances = building.nodes("[entrance]").size();

Related Repositories