gistfile1.txt

<?xml version="1.0" ?>
<Map bgcolor="rgb(255,255,255)" srs="+init=epsg:4326">
    <Style name="NYC_Structures4326_style">
        <Rule>
            <PolygonSymbolizer>
                <CssParameter name="fill">rgb(78,110,187)</CssParameter>
                <CssParameter name="gamma">0.7</CssParameter>
            </PolygonSymbolizer>
            <LineSymbolizer>
                <CssParameter name="stroke-width">0.96</CssParameter>
            </LineSymbolizer>
        </Rule>
    </Style>
    <Layer name="NYC_Structures4326" srs="+init=epsg:4326">
        <StyleName>NYC_Structures4326_style</StyleName>
        <Datasource>
            <Parameter name="file">4326/NYC_Structures4326.shp</Parameter>
            <Parameter name="type">shape</Parameter>
        </Datasource>
    </Layer>
</Map>




#!/usr/bin/python
#

import mapnik
import sys, os

if __name__ == "__main__":

    mapfile = "mapnik.xml"
    map_uri = "image.png"

    ll = mapnik.Envelope(-74.46, 40.47, -73.56, 40.906)

    z = 9
    w = 600 * z
    h = 600 * z

    m = mapnik.Map(w,h)
    # for details on fixing aspect ratio see:
    # https://lists.berlios.de/pipermail/mapnik-users/2010-September/003581.html
    mapnik.load_map(m,mapfile)
    lonlat = mapnik.Projection('+init=epsg:4326')
    merc = mapnik.Projection("+init=epsg:900913")
    m.srs = merc.params()
    transform = mapnik.ProjTransform(lonlat,merc)
    merc_bbox = transform.forward(ll)
    m.zoom_to_box(merc_bbox)
    mapnik.render_to_file(m, map_uri)