# Spatial Module

Nitrite Spatial module provides support for spatial queries. The module uses JTS library for spatial operations.

Add Spatial module to your project:

Add the Spatial dependency to your pom.xml file:

<dependency>
    <groupId>org.dizitart</groupId>
    <artifactId>nitrite-spatial</artifactId>
</dependency>

Add the Spatial dependency to your build.gradle file:

dependencies {
    implementation 'org.dizitart:nitrite-spatial'
}

To use Spatial module, you need to load the SpatialModule while opening the database.

Nitrite db = Nitrite.builder()
            .loadModule(new SpatialModule())
            .openOrCreate();

If Nitrite is using the default SimpleNitriteMapper, then the SpatialModule will automatically register the GeometryConverter with the mapper. If you are using your own custom mapper, then you need to register the GeometryConverter with the mapper.

GeometryConverter is an EntityConverter which is used to convert Geometry object of JTS to Document and vice-versa. It is used to store the Geometry object in the database.

If you are using Jackson module for serialization, you need to register the GeometryModule with Jackson as well.

Nitrite db = Nitrite.builder()
            .loadModule(new SpatialModule())
            .loadModule(new JacksonMapperModule(new GeometryModule()))
            .openOrCreate();

The GeometryModule is required to serialize the Geometry object of JTS via Jackson.

Spatial module uses R-Tree index to store the spatial data.

To create a spatial index, you need to pass the index type as SpatialIndexer.SPATIAL_INDEX while creating the index.

collection.createIndex(IndexOptions.indexOptions(SpatialIndexer.SPATIAL_INDEX), "location");

Spatial module supports several filters to query spatial data. To know more about filters, please refer to Spatial Filters.