I'm developing an OpenGL application. I need to have a model of planet earth spinning around (with the waters in blue, the land in green). My question is not dealing with the OpenGL / graphics ... but with the data.
Where can I get this data? (Of the boundaries of the various countries). Bonus points if you also know where I can get elevation data for each country.
You can get elevation from SRTM data from NASA. For country boundaries, I would download a shp file from a site like Geocommunity. You then can find one of the many open source shp file parsers to parse the data. Another possiblity for elevation data is DEM data. Here's a discusion on working with DEM data. You can also find tile data from Nasa.
For boundaries you might want to have a look at one of those:
Natural earth
Global Admin Areas
Geonames
Related
I'm in need of acquiring the coordinates of the outlines of all the water bodies inside a country, with the exception of "Sea" or "Ocean" water. Right now, I'm manually outlining the lakes and rivers but it is not a sustainable solution for the magnitude of the application I'm developing.
Even if I can only obtain the data of Lakes or Rivers, that would be a great start. I'm specifically interested in the countries of Malaysia, Brazil and the Dominican Republic.
My situation brings me to the question of, where does Google obtain its data? Are these data sets available?
Google gets this data usually from TomTom, (former TeleAtlas).
The coordinate polygons of that data is not available, at least not without paying much money.
This data is usually extracted from aerial fotos.
For research projects it might be possible to ask TomTom via your University.
An alternative professional quality source is the product NavStreets from Here (former Nokia).
For free you could try OpenStreetMap. You would get coordinates.
Unfortunateley the OpenStreetMap data is not always clean or closed polygons.
The quality depens much on the country. You can check the countries
first by looking in the web browser: https://www.openstreetmap.org/relation/57963
Geofabrik.de provides OpenStreetMap data converisons and extractions of specific countries, e.g in pbf and shp file format, you might check this to.
read further here:
http://wiki.openstreetmap.org/wiki/Waterways
I'm interested in implementing some data visualizations as map layers. But I'm interested in generating data layers only above land area (land cover). A good example would be to plot population density over a coastal city. What is a good approach for this, when it comes to the data source and how to actually display layers with such detailed boundaries?
Technically, so far I'm using Leaflet.js and tiles based on OpenStreetMaps, but the question is not necessary technology specific. Also, I'm not interested in plotting this for the whole planet, but for areas of a few hundreds square kilometers (for e.g. a coastal city).
To better give an idea of what I'm interested in, this Koordinates map is something that is similar to what I'm interested in. However, I need something a bit more detailed on the borders.
Usually you need a desktop or server based GIS such coverage, but not JS to do the processing on the client side.
How you do the mapping (here: linking statistical data and land areas) depends on your data itself. You can load OSM based shape files into QGIS and do some python scripting or using the PostGIS commands to link your data and choose a map style.
Another idea would be http://geocommons.com that allow easy visualization if you upload CSV files.
Depending on your area of interest, you can obtain some highly detailed shapefiles from numerous sources. Especially if the local area provides GIS data to the public (many larger coastal cities do, e.g. New York, London). From there, you can create a GeoJSON text of the geometries (here's a free tool for that). Parsing the JSON is very simple and it's very easy to add it to leaflet maps. You can even get creative and add more keys to each geometry object with the data you want to visualize.
Hi there does anyone know a way, programatically or using a tool,
that I could create say a course around a Country and convert it into a series of GPS coords?
What I want to do is create a track then using the state of some unrelated data, lets say 0-100% completion, map that progression as a representation on the map.
I.E if the data is 30% completed, then represent a little running man icon on the map having walked 30% of it.
any ideas anyone? Thanks!
You can create a track in google earth and save it as KML. KML is a DSL that most geographic viewers understand. Once you have the KML, mining this data is a different story and theres no real rule to follow. You could parse directly the kml using a XML parser and get fun with your school math and vectors or you could download a KML parser library to get quicker results.
I have an application that draws a vector map of the 50 United States. Each state is a polygon. These polygons change color as the state of the application changes.
I obtained the coordinates I'm using now by laboriously tracing a scanned in map with a mouse, recording the screen coordinates as I did so. As you can imagine my vector map is pretty ragged. I'd like improve the appearance of my maps by using real boundary coordinates for each state, and in the future use other political boundaries in my app such as counties or congressional districts.
I know nothing about GIS systems, nothing at all. I do think that given a vector of lat/long pairs for the borders of each political entity I could convert the lat/longs into screen coordinates. I used to be an Air Force navigator, so I'm comfortable with lat/long calculations.
Bottom line: I need an open source or public GIS database system that could spit out a list of Lat/Long pairs for the boundaries of the fifty States.
Can someone provide a pointer to such a database and hopefully a tutorial of some kind describing how to extract political boundary information from it?
Thanks in advance!
The Census Bureau provides the TIGER data sets that include shapefiles for state outlines (and much, much, more). The downloads are in ESRI Shapefile format, which can be opened by most GIS applications, such as the easy to use open-source QuantumGIS. To convert the shapefiles to a format that's easier to work with, see this question. Once you've got the vector data into your program, you'll probably realize that it's more detailed than you want. Check gis.stackexchange.com for some tools to simplify the polygon outlines. Once you've got the sets of points you want, you may want to use the PROJ library to handle the projection of the points on to your map.
Is there a way I can build terrain data in a simple way from sources like Google Maps. I am not interested in heights but a simple 2D representation will be good enough.
For instance, I am trying to represent a terrain using the roads and buildings inside a map to model a traffic simulation. Representing objects like buildings is necessary so that when my cars are moving on a road, they should know when to take a turn etc. Are there any standards for representing these?
There are dozens of map standards. also map data tends to be very expensive, although there are some low cost and open source map sources. Eg. OpenStreetMap, and for the US, Tiger/Line.
I would also read up on, at least, some introductory GIS - I think you'll find the field is much bigger and more complex that you are initially thinking.