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34

Of course it is ultimately up to you, but i would hesitate to call working with Open Street Map a waste of time. While it is true that the OSM user base is small right now, there are factors that affect both Google and OSM. The primary issue is that now that Google has started to charge for levels of use of their API, a number of companies and organizations ...


18

It's worth noting that at Google Maps, you're not 'donating' your geographic knowledge -- you are giving your geographic knowledge to a for-profit corporate entity, who have a duty to their shareholders to use their position as a majority data holder in the worldwide map data market to increase the value of their company. This means that the data that you ...


13

I saw this answer on the Openlayers mailing list a few days ago. You need to make sure you are providing a version, such as v=3.6: <script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?sensor=false&v=3.6"></script> Then it should disappear. -- May 17, 2012 edit: I just saw that this problem has returned on the ...


12

There exists no map of the entire earth in which all (true, spherical) circles remain truly round. However, there are ways of mapping the earth in which almost all sufficiently small circles are round. These are based on conformal projections. By definition, the changes that a conformal projection makes to distances within small areas are of two types ...


11

In addition to the other excellent comments here, the biggest advantage I see to OSM data is two aspects of ease of access: Editing is far more straightforward, particularly with a large area that is previously unmapped, or (worse yet) badly mapped. JOSM, QGIS and other tools let you update large areas, correct or add data in bulk. Working on areas here in ...


10

Direct tile access is not allowed by Google (and this is what ArcBruTile is doing). Usually this will get your IP address banned for awhile but they could also come after you for violating their TOS. fwiw, Arc2Earth will be adding support for this functionality in the next build. Instead of needing a Google Maps Premium license, you can purchase access at ...


10

I guess your circles look something like this: (Source: Esri mapping center blog) You will want to use Web Mercator EPSG:900913 instead of WGS84 EPSG:4326 for perfect circles More on this topic and an example of how the circles look like in Mercator: Tissot's indicatrix helps illustrate map projection distortion To make openlayers use Mercator, you ...


8

You can do it with GeoServer. Installing and "linking" Geoserver to Postgres/PostGIS database is quite easy. KML KMZ Output


8

There are two possibilities. The more likely is that you have Chrome zooming the page in or out, which introduces the white lines. Do cmd-0 (or ctrl-0) and see if that fixes it. Otherwise, add that line to your CSS file, which might be site.css or whatever. Add it to the bottom, though it doesn't matter much. A live example would make this question easier ...


7

Use WMS instead of WFS - then all you are sending is a picture of your data instead of your actual data.


7

The Mercator projection has been around for a few hundred years. I don't know when the ellipsoidal version of the algorithm came into being (I don't have my reference books at my current location), but certainly the spherical version is quite old. Both versions certainly pre-date the use for web-based map imagery. By ellipsoidal / spherical, I mean that the ...


6

Yes. ArcBruTile - Tile Services in ArcGIS Desktop ArcBruTile display tiles from OpenStreetMap, Bing, Google, SpatialCloud and TMS/WMS-C Services in ArcGIS Desktop. Update: looks like references to Google have been removed from the ArcBruTile site, likely because, as commenters point out, what they're doing violates the Google Maps ToS.


6

You can restrict number of request/retrived features/etc per second/hour per ip. Annother approch would be converting it to harldy readable format (i.e. custom projection) or rasterizing vector data (as Google/MS does). You may also try to encrypt it, but I think, as cipy said, the best way is not to show it ;)


6

1.- Nope, only the other way around. 2.- Not directly, but you can use Google Fusion Tables to do some basic queries, avg, max, min and some basic mathematical operations.


6

Yes, always anticipate coordinates to fluctuate. Though the building is not likely to shift on the earth's surface, using coordinates as identifiers/keys for addresses is a bad idea because the data set is going to move from underneath you: Accuracy a matter of definition. Is an address most accurately pinned at its mailbox, or its largest structure, or ...


5

Keep the source off the Internet. Implement a proxy webpage and check the parameters/urls. Only allow certain parameters etc, if they don't match the proper ones reject. This could allow you to limit usage by IPs etc.. If your users login. You can add token handling. If you use ArcGIS Server here is esri's page with sample proxy code: ...


5

Google's tools do not provide any way to do this kind of thing built in. While you might be able to do this by routing to a sufficient number of locations and checking the time, another tool that you might be interested in is Graphserver. GraphServer is a multimodal trip planner, which can take data from OpenStreetMap and other data sources. Some of the ...


5

hallo first, in the post in stackoverflow the discussion is about getting a GPS point and say if it is a building or a road. AFAIK, GPS does not have that precision. I never expect a GPS point to be more precise than 10 meters. of course it often is a little better than that but it can also be much more wrong. In Routing GPS units the software often snap ...


5

ArcMap has a Geoprocessing Tool that Adds XY Coordinates as two new fields in the attribute table. If you're set up in a projected coordinate system, you'll need to first change over to the geographic system in order for the output of the tool to be in Lat Long. Alternatively you can open a new map, set the data-frame to WGS 84 (Right-click 'Layers' in the ...


5

Your question contains a number of sub-questions - this answer addresses solving the server side part of spell checking. A while back I've implemented a spelling corrector for addresses based on Peter Norvig's How to Write a Spelling Corrector. Instead of using books to build your training corpus, your dictionary will be based on words tokenized out of ...


5

Well most people say Osmand is best as Android. Lacking of further knowledge, I can't judge on your particular case. You need to know what features you want a app for endusers or for mappers? support for smartphone or tablet? online or (full offline)? routing with different profiles? POI search, address lookup? OpenSource / free / commercial app? With ...


4

The answer depends on how the question is interpreted. One interpretation is, "Given that a GPS point is known (or assumed) to lie either on a building or on a road, what are the odds that it lies on the road?" To find this, compute a grid representing a 2D Gaussian function whose standard deviation equals the expected error in the GPS position. Use a ...


4

Looks like a custom function (do view-source on it). You'll need jQuery to use it: $(function(){ // Loop through all the sets of before and after pics $(".beforeafter").each(function(){ // Set the container's size to the size of the image ...


4

Not sure if this is "legal" but i just made it go away with CSS. .olLayerGoogleCopyright {display:none;} UPDATE Apparently this violates the terms of use: By doing so, you violate the Terms of Use. Instead, you should use a more recent version of OpenLayers - this problem was fixed in 2.11. Are you using 2.11? Apparently it's no longer a ...


4

Drag Marker and Geocoder with Coordinates https://gmaps-samples-v3.googlecode.com/svn-history/r49/trunk/draggable-markers/draggable-markers.html Entire code: <html> <head> <meta name="viewport" content="initial-scale=1.0, user-scalable=no" /> <script type="text/javascript" ...


4

Google has a permissions tool here. When you click through the options, it seems like your use of the map (academic, in print-media) would probably fall under fair-use so long as you do not obscure the copyright. Is it possible to make the same image using OpenStreetMap?


4

As far as I know there is no way to use Google Street View in QGIS. QGIS without Globe does not offer 3D capabilities. Globe is a work in progress and currently does not work on Windows according to Sourcepole (http://sourcepole.ch/the-state-of-qgis-globe).


4

For the points you gathered from google maps, you should use WGS1984: GCS_WGS_1984 Authority: Custom Angular Unit: Degree (0.0174532925199433) Prime Meridian: Greenwich (0.0) Datum: D_WGS_1984 Spheroid: WGS_1984 Semimajor Axis: 6378137.0 Semiminor Axis: 6356752.314245179 Inverse Flattening: 298.257223563


3

http://help.arcgis.com/en/webapi/flex/samples/index.html#/Surface_Profile/01nq00000041000000/ Geoprocessing Tasks>Surface Profile


3

I haven't got a full answer but an important point is the context of the building and the road. GPS accuracy falls dramatically in a very built up area because the radio signals are obscured by and bounce off buildings. So GPS readings in the country by a low building will be far more accurate than in a skyscaper 'canyon' as you get in major cities.



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