This plugin supports reading tiff and geotiff files.

Tiled or Stripped tiff files are required and when rasters are small < 200-300 MB this driver is faster that the GDAL plugin.

If files are larger it is recommended to build GDAL overviews (with gdaladdo command) and instead read with the GDAL plugin.

• Note: overviews support is available only in Mapnik >= 0.7.0.

A drawback(or advantage!) of this plugin is that it requires manually setting the file bounds.

• hint: create a GDAL datasource from your tiff in python, call the envelope() method to get the bounds, and use those.

For other plugins see: PluginArchitecture

Installation

To check if the raster plugin built and was installed correctly you can do:

>>> from mapnik import DatasourceCache as c
>>> 'raster' in c.plugin_names()
True

Parameters

See: http://svn.mapnik.org/trunk/docs/api_docs/python/mapnik-module.html#Raster

Styling

To style a layer use the RasterSymbolizer

Usage

Python

See the docstring at: http://svn.mapnik.org/trunk/docs/api_docs/python/mapnik-module.html#Raster

XML

<!-- NOTE: must be in the same SRS as your map-->
<Layer name="Raster">
        <StyleName>raster</StyleName>
        <Datasource>
                <Parameter name="type">raster</Parameter>
                <Parameter name="file">/path/to/my/raster/file.tiff</Parameter>
                <Parameter name="lox">min_x</Parameter>
                <Parameter name="loy">min_y</Parameter>
                <Parameter name="hix">max_x</Parameter>
                <Parameter name="hiy">max_y</Parameter>
        </Datasource>
</Layer>

C++

Plugin datasource initialization example code can be found on PluginArchitecture.

A Raster datasource may be created as follows:

{
    parameters p;
    p["type"]="raster";
    p["file"]="/path/to/my/raster/file.tiff";
    p["lox"]=min_x;
    p["loy"]=min_y;
    p["hix"]=max_x;
    p["hiy"]=max_y;

    Layer lyr("Raster");
    set_datasource(datasource_cache::instance()->create(p));
    lyr.add_style("raster");
    m.addLayer(lyr);
}

Further References