How to render plain bus routes?

I already rendered tram and rail lines, but i have problem render bus routes. I use this script to render rail lines:

#!/usr/bin/env python import mapnik stylesheet = 'schema.xml' image = 'output.png' m = mapnik.Map(4000,2671) mapnik.load_map(m, stylesheet) m.zoom_all() mapnik.render_to_file(m, image)

and this scheme:

<?xml version="1.0" encoding="utf-8"?> <Map background-color="white" srs="+proj=latlong +datum=WGS84"> <Style name="rail"> <Rule> <Filter>[railway] = 'rail' </Filter> <LineSymbolizer stroke="black" stroke-width="1"/> </Rule> </Style> <Layer name="rails" status="on" srs="+proj=latlong +datum=WGS84"> <StyleName>rail </StyleName> <Datasource> <Parameter name="type">osm </Parameter> <Parameter name="file">map.osm </Parameter> </Datasource> </Layer> </Map>

To render tram lines I only changed filter to [railway] = 'tram'. I tried different filters to render bus routes, but nothing worked. I want only black lines 1pixel wide on white background. How can I do it?

Edit: I have rendered bus routes from postgis database. I imported the map.osm using osm2pgsl. And changed Datasource in schema.xml. The problem is different aspect ratio. This happen when i overlap the images (clipped overlaping images). Red - tram, azur - bus. Bus image has white border on left and right side.

Edit2: Ratio problem solved, I have bad srs projection in layer