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23

If you are designing a map you plan on overlaying over google maps or virtual earth and creating a tiling scheme then i think what you are looking for are the scales for each zoom level, use these: 20 : 1128.497220 19 : 2256.994440 18 : 4513.988880 17 : 9027.977761 16 : 18055.955520 15 : 36111.911040 14 : 72223.822090 13 : 144447.644200 12 : 288895.288400 ...


21

Note: This rant will be updated as I go I'm no computer or ArcGIS pro by any means, but here's what I do: Base Files/DBS These are files that are "raw" in nature and constitute the base of all my analysis These files, databases, and data are hosted outside of my projects folder, and are hosted on my internet server, local computer, and dropbox. I always ...


21

Enjoy http://maps.vlasenko.net/soviet-military-topographic-map/ Update: There seem to be some torrent cache's of http://poehali.org/maps/ search at your own risk. Below are some websites with varying degrees of content and geographic coverage. University of Georgia Libraries: http://www.libs.uga.edu/maproom/collections/soviet.html MadMappers.com Africa ...


18

No depending on the Map (90% North is up) dependent on projection This Map: North is in all directions out from the centre (or South in all directions to the centre) - also has the graticule and text curved inline with the grat. (uses the polar stereographic projection.)


16

Not that easy. Given the projection, the size of the tile pixels depends on the latitude of the area you're interested in. Then in terms of transforming tile pixel size in screen pixel size, it depends on the screen and the resolution the data is displayed, the dpi your screen is using.


15

The most obvious use of North arrows are if UP in your map deviates from true north and this isn’t obvious to the reader. Beaulieu, de, 1646 Another use may be as a decoration, but then there is a need for something a bit juicier than the arrows provided by common GIS systems.


15

In addition to the ones posted here, in the R gallery website there are a few examples: http://gallery.r-enthusiasts.com/graph/SuperStorm_Sandy_170 http://gallery.r-enthusiasts.com/RGraphGallery.php?graph=146 http://gallery.r-enthusiasts.com/RGraphGallery.php?graph=113 other websites with tutorials and good mapping examples in R: ...


14

It's generally implied that North is up but I'm not ready to say they're pointless. In my daily work, I see a fair number of CAD as-built drawings. The North arrow provides much needed context. If we're talking about the web, then I'm fine with leaving them out and I think the major web map vendors (google, bing, esri) agree.


12

ST_Distance only calculates the distance between two features "as the crow flies". pgRouting on the other hand calculates the actual distance along a network (e.g. road network). Those are two different things and it depends on your use case whether ST_Distance is sufficient or not.


12

This will not be a cannonical answer but just some of my experiences. A real archivist can give you a fuller answer. PAPER: Paper is a tricky medium, whether you are storing maps or have a library of books. The problems of degeneration are compounded for maps because climate can not only causes the paper to degenerate but can also cause the paper to ...


12

I would drop using the maps package and find a state shapefile. Then load that into R using rgdal, and then do some polygon overlay work. library(raster) # use state bounds from gadm website: # us = shapefile("USA_adm1.shp") us <- getData("GADM", country="USA", level=1) # extract states (need to uppercase everything) nestates <- c("Maine", "Vermont", ...


12

Here is an approach using extract() from the raster package. I tested it with altitude and mean temperature data from the WorldClim website (I limit this example to altitude, temperature works similar), and an appropriate shapefile of the US containing state borders is to be found here. Just download the .zip data and decompress it to your working directory. ...


11

To help you understand the maths (not a precise calculation, it's just for illustration): Google's web map tile has 256 pixels of width let's say your computer monitor has 100 pixels per inch (PPI). That means 256 pixels are roughly 6.5 cm of length. And that's 0.065 m. on zoom level 0, the whole 360 degrees of longitude are visible in a single tile. You ...


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 ...


9

Below you find some examples: Service for historical Warsaw (it is available in Services tab). Maps of Paris Maps of London Countries of the World by ONZ The Federation of East European Family History Societies - MAP Library A new one: Archive of maps of military technical institute 1919-1939 If you are still interested the website of the Military ...


9

Google has built their own vector map rendering engine based on OpenGL ES version 2: https://developers.google.com/maps/documentation/android/start#requiring_opengl_es_version_2 Here's a link about OpenGL ES on Android: http://developer.android.com/training/graphics/opengl/index.html OpenGL lets you leverage the underlying power of the GPU and get ...


8

I've found the only time that I've needed to include a North arrow on my maps is to differentiate between grid north, true north and magnetic north. Doesn't come up often though. Also, I totally agree with @haakon_d that they might be used as decoration, but IMO there's always a better option (including the minimalist option of not including one).


8

I remember being taught that a north arrow must be present always except in few specific cases, which actually cover 99% of maps. You typically do not need a north arrow when: there is a geographic grid present the map presents a well known area to the map user, e.g. the map of the world, Europe, or your whole country on one sheet the map is part of a ...


7

There is such a table in the documentation of the Virtal Earth Tile System from Microsoft. But as said by GuillaumeC the values depends on the latitude and on the screen resolution. The table gives values as measured at the Equator and at a screen resolution of 96 dpi. PS: Not sure of that, but the zoom levels by Microsoft might be shifted by 1 in ...


7

I like Esri's ArcGIS API for Microsoft Silverlight/WPF, and also the ArcGIS Viewer for Silverlight. You can use Bing with these, or base maps from ArcGIS.com. Also, consider using SQL Server 2008 with Sql Server Management studio to prototype spatial sql queries. Isaac Kunen's blog is a good resource. Best when used with the Sql Server Spatial Tools from ...


7

I'd recommend using TileMill to generate the tiles, it can save them out to a variety of formats including as mbtiles bundles which can be used for offline applications. Tilemill will give you cartographic control over the maps, and produces beautiful results. Alternatively, you could download the styled data from Cloudmade, the .img files should be full ...


6

I think that North Arrows are similar to cargo-cult programming. "Every map up to now has had one, so we have to have one on this map too." The only reason I can think of to include a North arrow is when the "top" of the map is not North, or when it is not immediately clear which direction is North.


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

Projections are like pushing string. As you try to preserve one aspect, you get distortions in some other parameter (e.g. distance or bearing). To preserve both shape and area you may need to consider an interrupted projection like Goodes Homolosine or the off-beat Buckminster-Fuller 'Dymaxion' projection. In these projections, the distortions are present ...


6

According to your question the very good example is on this link . This link contains various beautiful map collections using R software . I am sure this will help you!!. I am also referring above site for reference.. Please let us know if you have any questions.. thanks..


6

The ebook "Data mashups in R" is just 40 Pages long and will walk you through an example project (mapping foreclosures in Washington DC) From the first reader-review : This book presents an interesting project, drawing together a number of data sources and geocoding them. I've once skimmed the PDF, want to have a closer look someday. It's on my ...


5

You can use the Mapping Wizard Tool to load in your text file of latitude and longitude coordinates. Just set the correct datum (usually World WGS84) to overlay them correctly. Guide to using the Mapping Wizard Tool: http://www.oocities.org/mapinfotutorial/wizard.html


5

You can load a kml file containing your polygons or create theme dynamically with the help of the Polygon class. Here is an example of creating a polygon but the simplest way is loading a kml file. Just be sure your Kml file is under the file size limit (which can change at any time). By default on the given example, I guess fill color is transparent, ...


5

You did not state that you only work with Desktop GIS software, so I'll share some of my experiences from the programming oriented mindset. Let me first start by saying that I agree with of the things @dassouki says. I think the most important thing is not how you organize, but that you do this. But to go on to my workflow. What I like about using a ...


5

The best projection that does not distort is a globe. All the others are compromises to project the objects onto a piece of paper. The attempt to do that "projection" distorts something. It can distort distance, angles, shapes, area. Some of these properties are preserved by various projections. But no projection can preserve them all. If you want to ...



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