Tile Choices
With the interactive map and router on this website there are a choice of different map tiles.- Locally generated custom tiles.
- OSM tiles.
In all cases the interactive maps on this site limit the range of tiles to reduce the number that need to be cached or generated.
Custom Map Tiles
The first choice (since November 2009) is a set of locally generated map tiles using a custom Mapnik XML stylesheet.The idea of using these tiles rather than the classic OSM ones is that the stylesheet has been modified to hopefully make them easier for use when walking and/or cycling.
OSM Map Tiles
The second choice of map tiles is a direct reference to the original OSM map tiles from the OpenStreetMap web site. This is a fallback in case the other option is not working.Generating Tiles
Generating your own tiles is quite complicated with several tools being required. There are several ways of generating tiles but the method that I have chosen is the same as the one used on the main OSM site.- osm2pgsql
- PostgreSQL database
- Mapnik renderer
- Mapnik stylesheets
- mod_tile
The process required is the following:
- Download OSM data
- For me this is a partial OSM planet database from GeoFabrik.
- Insert into database
- The program osm2pgsql reads in the downloaded data and stores it in a Postgres database from where it can be accessed for rendering.
- Serve tiles on demand
- The package mod_tile contains both a background rendering task renderd and an Apache module mod_tile for efficiently serving tiles.
- Rendering tiles
- To actual perform the rendering of tiles requires both the Mapnik renderer and some stylesheets based on the ones used on the main OSM site.
Getting all of this working is quite complicated but there are web pages to help. The best place to start is the OSM wiki page for Mapnik which has links to several other locations.
Custom Stylesheets
The idea of my custom stylesheets is to improve the standard OSM stylesheet with more information (or better presented information) that is also targetted more to walkers and cyclists.Highway Names
There are two changes for highway names. The first is that names of major roads are written along the road rather than within a symbol on top of the road. This causes less obscuration of the details at the side of the road. The second change is to use a Mapnik option to avoid placing names on sharp corners.
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| Standard OSM map tile | Custom map tile |
Highway Widths
The width of service roads, byways and tracks have been increased at zoom levels 13 and higher. This is to ensure that the following changes can actually display something useful when they overlay more information on the existing highways.Highway Colours
The colours of the track and byway highway types have been made less saturated so that they do not dominate the image (not shown in examples).Public Access
Where transport by foot, horse or bicycle is tagged as designated or permissive on a highway other than a footway, bridleway, path or cycleway the highway is overlayed with the normal footway, bridleway or cycleway markings.This makes the maps better for walking where public footpaths can often follow tracks or service roads which would otherwise not be marked as accessible by foot.
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| Standard OSM map tile | Custom map tile |
Unfortunately not enough public access along tracks or service roads is marked as designated for this to make much difference.
Walking and Cycling Routes
Any route relations that are for foot, hiking or bicycle are marked by a broad but faint line covering the entire route. The marking is colour-coded to match the footway or cycleway colour-scheme. This change is only visible from the zoom level where the footpaths are visible (level 13).As an experiment the name of the route is also written on the route. This is only partly succesful because the name then obscures the type of highway beneath it.
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| Standard OSM map tile | Custom map tile |