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| <html> |
| <head> |
| <title>Apache Lucene Spatial-Extras Module</title> |
| </head> |
| <body> |
| |
| <h1>The Spatial-Extras Module for Apache Lucene</h1> |
| |
| <p> |
| The spatial-extras module, new to Lucene 6.5, is the new home for the original |
| lucene spatial module. |
| The principle interface to this module is a {@link org.apache.lucene.spatial.SpatialStrategy} |
| which encapsulates an approach to indexing and searching |
| based on shapes. Different Strategies have different features and |
| performance profiles, which are documented at each Strategy implementation |
| class level. |
| </p> |
| <p> |
| For some sample code showing how to use the API, see |
| SpatialExample.java in the tests. |
| </p> |
| <p> |
| The spatial-extras module uses |
| <a href="https://github.com/spatial4j/spatial4j">Spatial4j</a> |
| heavily. Spatial4j is an ASL licensed library with these capabilities: |
| <ul> |
| <li>Provides shape implementations, namely point, rectangle, |
| and circle. Both geospatial contexts and plain 2D Euclidean/Cartesian contexts |
| are supported. |
| With an additional dependency, it adds polygon and other geometry shape |
| support via integration with |
| <a href="http://sourceforge.net/projects/jts-topo-suite/">JTS Topology Suite</a>. |
| This includes dateline wrap support.</li> |
| <li>Shape parsing and serialization, including |
| <a href="http://en.wikipedia.org/wiki/Well-known_text">Well-Known Text (WKT)</a> |
| (via JTS).</li> |
| <li>Distance and other spatial related math calculations.</li> |
| </ul> |
| </p> |
| <p> |
| Historical note: The new spatial-extras module was once known as |
| Lucene Spatial Playground (LSP) as an external project. In ~March 2012, LSP |
| split into the spatial module as part of Lucene and Spatial4j externally. A |
| large chunk of the LSP implementation originated as SOLR-2155 which uses |
| trie/prefix-tree algorithms with a geohash encoding. That approach is |
| implemented in {@link org.apache.lucene.spatial.prefix.RecursivePrefixTreeStrategy} |
| today. |
| </p> |
| |
| </body> |
| </html> |
