Awesome
tilelive-mapnik
Renderer backend for tilelive.js that
uses node-mapnik to render tiles and
grids from a Mapnik XML file. tilelive-mapnik
implements the
Tilesource API.
Installation
npm install tilelive-mapnik
Though tilelive
is not a dependency of tilelive-mapnik
you will want to
install it to actually make use of tilelive-mapnik
through a reasonable
API.
Usage
var tilelive = require('tilelive');
require('tilelive-mapnik').registerProtocols(tilelive);
tilelive.load('mapnik:///path/to/file.xml', function(err, source) {
if (err) throw err;
// Interface is in XYZ/Google coordinates.
// Use `y = (1 << z) - 1 - y` to flip TMS coordinates.
source.getTile(0, 0, 0, function(err, tile, headers) {
// `err` is an error object when generation failed, otherwise null.
// `tile` contains the compressed image file as a Buffer
// `headers` is a hash with HTTP headers for the image.
});
// The `.getGrid` is implemented accordingly.
});
Note that grid generation will only work when there's metadata inside a
<Parameters>
object in the Mapnik XML.
The key fields are interactivity_layer
and interactivity_fields
. See an
example in the tests. These Parameters
are normally added by the application that creates the XML,
in this case CartoCSS