Stylesheets

A stylesheet is a configuration file for a renderer that determines the content (what should be displayed) of a map and its style (how the content is displayed). The stylesheet contains the answers to questions like 'what types of roads should be shown on the map' and if so, 'What color should these types of roads be ?' and 'What should be the width of the roads ?'

There are different formats for stylesheets:

Format	File	renderer	Note
Mapnik XML	.xml	Mapnik
CartoCSS	.mml, .mss	Mapnik	Has to be converted to Mapnik XML.
Mapbox Style	.json	Mapbox GL	Also used by MapLibre.
MapCSS	.mapcss	used by several	Used by overpass turbo, JOSM and other projects.

Default style

www.openstreetmap.org by default uses the OpenStreetMap Carto style, which was ported in November 2012 from the previous Mapnik style.

The other featured tile layers are CyclOSM, OpenCycleMap, Transport Map, Tracestrack Topo and Humanitarian.

Stylesheet editors

CartoCSS styles can be edited with TileMill and Kosmtik.

Mapbox styles can be edited with Mapbox Studio and Maputnik.

Resources

• 2016-05-13: The end of CartoCSS - Tom MacWright (note that CartoCSS is still maintained and still heavily used by OSM)
• 2012-11-02: CSS For Maps - Tom MacWright

Stylesheets elsewhere

What can we learn from the way non-osm systems define map styles? and what compatibility can we provide?

• google maps "StyledMaps" config
• a geographic centered color chooser

Discontinued software

• Cascadenik is a discontinued Mapnik XML-preprocessor that inspired CartoCSS
• Osmarender had its own Osmarender stylesheets and Rules
• Gosmore has its own Gosmore stylesheets