User:Ff5722/China armchair mapping guide
China armchair mapping guide
In this guide I will show you how to recognize amenities and other objects from satellite imagery, so that armchair mappers can add these.
Every country constructs its infrastructure and architecture differently, so for foreign mappers it can be difficult to recognize objects that may be obvious for someone who is familiar with them. Of course, nothing is 100% accurate without surveying on the ground, but I am confident that - provided the satellite imagery is not outdated - these objects will be easy to recognize once you see some examples. Also, of course not everything is different in China, so don't expect eye opening examples. This is just to give more confidence in identifying features.
Amenities and POIs
Middle school
Pretty much always consists of a sporting ground (usually a concrete pitch or soccer pitch surrounded by an oval track), and a rectangular building housing the classrooms. Usually located in the middle of a residential block. In case of rural areas, schools still include a pitch (may be sand), but the buildings are usually a number of barracks. If the villages are small, a school may be surrounded by farmland, and be located centrally between the villages.
Kindergarten
Recognizable by green floor of the outdoor playground.
Place of worship
[1] Familiar traditional Chinese architecture. Often, but not necessarily located on a hill. Mosques usually look different. I have not found a way to distinguish Buddhist and Taoist temples on satellite imagery.
Fuel stations
[2] Always have a roof and small building next to it like most fuel stations in Europe. Some fuel stations have (red) pyramidal roofs. Fuel stations are usually located near important intersections or near motorway junctions.
Bus stop
Probably only identifiable along major roads. A short parking space and shelter can be seen. Bus stops are usually located near school, intersections of some importance and entrance points to closed residential communities.
Bus station
How to recognize:
- Large building (rectangular, but may also have more creative shapes)
- Front parking area with both buses and cars (taxis?)
- Rear parking space with only buses
- Buses ready to board park at the rear of the building perpendicular to the building
- Bus stop for buses not terminating here are located near the road, like other bus stops
Tag: amenity=bus_station
Marketplace
[5], [6] (the blue roofed building on the left), [7] (can you spot the fuel station as well), [8]
Smaller marketplaces (for food usually) are just a long buildings, often with blue (sheet metal or plastic) roof. They may be quite long, and thus creating a pedestrian street. Larger ones may be a single huge hall, or multiple buildings with service roads in between in a neat grid layout.
Tagging: amenity=marketplace
Cemetery
Either a collection of rectangular marked areas on hillsides, with no supporting facilities or buildings around (type 1), or a dense, regularly arranged collection of white markers (type 2).
Prison
How to recognize:
- Walls with towers at the angles
- Wide service roads within the walled area
- Multiple identical buildings of medium height
- Open area for sporting or assembly
Landuse
Military areas
Usually walled entirely, but just a low wall. And look out for green trucks being parked everywhere.
Roads
The conventions as described in WikiProject China and Chinese tagging guidelines should be used if the official classification is known.
Motorway
For 2x2 lane motorways, in general the distance between the two ways should be 10.5 meter, use the parallel ways tool in JOSM.
If you see toll stations on the exits, add toll=yes.
Trunk
In cities: at least 4 lanes, busy intersections are (partially) grade-separated (bridge for traffic following straight on).
Primary
Connect county level cities. Major city thoroughfares both for local and long distance traffic. Motorway links usually connect directly to these roads. Often a bypass is constructed around towns/town-level settlements.
Secondary
Connects township level administrative centres (i.e. towns) and connects neighbourhoods in cities. Usually well maintained and quite wide. In urban areas often 2 lanes per direction and/or parallel service road for slow traffic and parking. Sometimes goes around village centres.
Tertiary
Connects larger villages. Important road within neighbourhoods (such as the grid roads in a high rise neighbourhood). Lowest level of through road on the countryside. On the countryside they are wider than the unclassified roads, and better maintained. In areas with unpaved smaller roads, they are usually paved. If unpaved, the tertiary roads are visibly wider than other roads.
Unclassified
Small roads that visibly do not allow high speeds. Often connects a village to a higher classified road. Usually no through road, but a dead end to a village or a loop through a few small villages before returning to the main road. If the village is very close to the main road, use highway=unclassified for the entire access road.
Service
Roads connecting one or a few commercial or industrial companies to the main road. Use service=alley for narrow residential roads that are not meant for and unsuitable for through motor traffic.