API

new mapnik.Map(width, height, [srs])

Returns a new Map object.

• width: An integer width for the map. Normally for tiled rendering this value is some power of 2, like 256 or 512 and matches the value for height.

• height: An integer height for the map. Normally for tiled rendering this value is some power of 2, like 256 or 512 and matches the value for width.

• srs (optional): A string. If provided, this sets the Map spatial reference system (aka projection). The format is the proj4 syntax. The default if you do not provide a value is +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs (which is equivalent to the shorthand of +init=epsg:4326 and comes from Mapnik core). The most common srs for tiled rendering is spherical mercator which is +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs +over (which is equivalent to the shorthand of +init=epsg:3857). Note: Mapnik >= 2.2.x has special handling for transforming between these common projections and detects them here.

Map#render(surface, options, [callback])

Renders the data in the map to a given surface. A surface can either be a mapnik.VectorTile, a mapnik.Image, or a mapnik.Grid.

new mapnik.VectorTile(z, x, y);

Returns a new VectorTile object for a given xyz tile uri. The assumed projection of the data is Spherical Mercator. Learn more about tile addressing at Maptiler.org.

• z: An integer zoom level.

• x: An integer x coordinate.

• y: An integer y coordinate.

VectorTile#getData()

Get the protobuf-encoded Buffer from the vector tile object. This should then be passed through zlib.deflate to compress further before storing or sending over http. Remember to set content-encoding:deflate if you want an http client to know to automatically uncompress. Or use zlib.inflate to uncompress yourself if working serverside.

TODO (rest of api docs - tracking at https://github.com/mapnik/node-mapnik/issues/235).

You can also take a look at the node-mapnik typescript definition file which offers intellisense in IDEs.