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Archive for May, 2008

Share Thematic Shapefile Maps Publicly On MapTube

Published at May 16, 2008 in Google Maps and shapefile. 0 Comments

Over a year ago, I posted on Google Map Creator, a program from the Centre for Advanced Spatial Analysis that lets you convert shapefiles into thematic colored maps for display in Google Maps. They’ve just created a new site called MapTube , “a place to put maps”, that collects links to maps created with Google Map Creator. You can search for maps covering a particular topic or area, and select multiple thematic maps for simultaneous display, to see if any relationships are visible between different datasets. Sliders set the transparency of the various maps displayed, and you can turn the legends on and off by clicking on the legend icon in the map thumbnail:

snapper1210893739215

You can also create an account that lets you add your own maps to MapTube, but you have to host the actual map data yourself on your own server; MapTube’s function will be to index the metadata, preview the maps, and allow people to view them in a Google Maps interface. The current maps are heavily Anglo-centric (not surprising), and limited in number; the site’s ultimate usefulness will depend on how many people actually wind up creating maps for it. It would help if they could add an interface to MapTube directly to the Google Map Creator program, and also if there were some way in the program to directly upload Google Map Creator maps to a centralized data server and pass that link directly to MapTube.



Plot Gazetteer Features In A Google Maps Interface

Published at May 15, 2008 in Web apps and cartography. 0 Comments

Gazetteers are listings of the names, types, and coordinates of both natural and man-made objects. For the US, the US Geological Survey’s Geographical Names Information Service (GNIS) contains name, feature type and position information for over two million geographic features in the US. Feature classes include both man-made (populated place, bridge, canal, etc.) as well as natural features (arch, spring, arroyo, woods). There are a number of similar databases for the rest of the world, like the NGA’s GNS Server, and the GeoNames site.

Another gazetteer website worth a look is SatelliteViews.Net. For geographical subdivisions, they have the US broken down by state, and the rest of the world by country. Select a state or country, then select the type of geographical feature you’re looking for, and get an alphabetical listing of them for that particular region. Select a specific feature, and you’ll get both the coordinates and a Google Maps display with the feature location plotted.

 

snapper1210892116159

They claim to have 5.9 million worldwide geographic features indexed and linked.

Hat tip to Coy0tea (JG).



Two Photo Geotagging Briefs

Published at May 14, 2008 in GPS and geotagging. 0 Comments

- Activity Workshop writes to say that his multi-platform GPS track management and photo geotagging application Prune has been updated (see earlier Prune posts here and here). New features include:

  • New map window in the View menu, showing points overlaid on OpenStreetMap images
  • New function to launch a browser showing the area in either Google Maps or OpenStreetMap
  • Handling of track segments, including loading, saving and exporting, and preservation during edit and undo
  • New function to merge track segments for the current selection, to make one single segment
  • Display of current and average speed on details panel
  • Status bar showing confirmation of actions
  • Much improved French texts thanks to generous user input

Written in Java, and runs on Windows, Mac and Linux

 

- Need to geotag a photo, but don’t have an application like Prune, GeoSetter or GPicSync handy? You can do it online using the Sunday Morning Rides GeoTag utility. Specify the location in a Google Maps interface, set the coordinates, upload the image (JPG only), and a minute or so later you’ll see the geotagged image (or part of it) on the web page. Then right-click on the image and save it to your computer. Even though you may only see part of the image on-screen, it does tag and save the entire image, apparently losslessly. Sunday Morning Rides also has an online GPX track builder and waypoint utility.



Greetings From Sunny Arizona

Published at May 13, 2008 in blogkeeping. 3 Comments

The view from my deck this morning …

 

Flagstaff May 2008 snowstorm

 

… and an unexpected guest for breakfast:

 

DSC00013



WorldWind Java Demo Apps

Published at May 9, 2008 in Google Earth. 0 Comments

I used to use the NASA open-source digital globe WorldWind a lot when it first came out, back when you had to pay to use Keyhole. But after Google bought Keyhole and released a free version of it as Google Earth, my WorldWind use dropped dramatically. Despite WorldWind’s strengths in some areas, I found Google Earth easier to use and create data for, and the larger user base meant that more content was being developed for it.

When WorldWind announced that it it was suspending development of the original version in favor of a Java version, I wasn’t really sure where they were going with that, apart from multi-platform. But after seeing this page of WorldWind demo apps, I had a major “Now I get it!” moment. I don’t think that WorldWind ever had a chance in its original format of being competitive with Google Earth as a general digital globe, but as an open-source application-driven geographic interface, it has a lot to offer. I look forward to what people will be doing with it in the future, especially when it graduates from its preview releases. Caution: you’ll need a 3D graphics card with updated drivers to make it work.

Via The Earth Is Square.



Projection Parameters / Point-Of-Origin For State Plane Coordinate Systems (SPCS)

Published at May 9, 2008 in coordinate conversion. 1 Comment

In a comment on this post, Theron was looking for command-line solutions for converting from UTM to SPCS coordinates on a Unix system; I pointed him towards OGR and GeoTrans as possibilities, and he found that GeoTrans offered a solution. But he also discovered that finding the projection parameters for SPCS wasn’t as easy as he thought it would be. He did track down a few using Google, and was good enough to send them on to me:

A simple, unorganized text listing

Links to both a CSV-listing and an Excel spreadsheet

To find the proper SPCS zone for your location, you can use the program described in the above-linked post, or try this website.



Static And Animated World History Maps

Published at May 7, 2008 in cartography. 0 Comments


The Mapping History site (from the University of Oregon and Universitat Munster) has dozens of static and animated maps illustrating US, European and Latin American history. Examples include “Cotton Production In The South: 1790-1860″; “Peasant Rebellions In Early Modern Europe”; and changes in the political status of South American countries. Some of the animated maps are slider-based (with a play button), and it’s obvious how they work. For other Flash-based maps, you’ll have to click on the map and select “Start” to begin the animation, and select “Key” to bring up the map legend.



Using The Demo Version Of Global Mapper As A Raster/Vector Data Viewer

Published at May 6, 2008 in GIS and coordinate conversion. 1 Comment


Global Mapper is a first-rate program for viewing and converting GIS data, raster (image and elevation) and vector. It opens over 100 different raster/vector formats, with on-the-fly support/display conversion of virtually every coordinate system / projection / datum you can think of, and some you might not (the Moon, Mars, the moons of Jupiter). It comes in a demo version with the following limitations (from the help file):

  • You will be unable to export data to any format.
  • You will be limited to loading a maximum of 4 data files at a time. With the full version, you can load any number of data files simultaneously.
  • No 3D capabilities (full version supports 3D views, viewsheds, line of sight, cut-and-fill volumen
  • You will be unable to load workspaces.
  • You will be unable to work with map catalogs.
  • You will be unable to download data from WMS map servers.
  • You will be unable to save rectified imagery to fully rectified files.
  • You will not be able to print to a specific scale (i.e. 1:1000).
  • You will have to endure a nagging registration dialog every time that you run the program.
  • You will not be eligible for free email support.

There’s one more, which is you don’t have the option of printing/exporting the screen display as an image file (though you can still print to a printer what’s visible on screen; zoom in to get a higher-resolution printout). Global Mapper’s display options for vector objects are also more limited than a standard GIS data viewer (e.g. no coloring by attribute for shapefiles). For those two reason, the TatukGIS viewer may be a better choice, since it lets you export the data view, raster or vector, as a high-resolution georeferenced raster image. But TatukGIS Viewer only supports about 30-odd raster and vector file formats, and doesn’t do on-the-fly re-projection. For examining the occasional odd data format you run across, in unusual projections/coordinate systems, and making a quick print, Global Mapper is good to have in your toolbox.

As a bonus, it also has a great line/area measurement function, which lets you modify the measurement units from metric to English and back on the fly, and copy them into the clipboard:

gmmeasure

The TatukGIS Viewer has a measure function, but it gives area only in the data’s native projection, less than useful if it’s in the geographic coordinate system (e.g. square degrees for area).

Finally, if you’re looking for an all-purpose data format converter with batch conversion capabilities, don’t need the considerable power (or expense) of FME, and don’t want to deal with the GDAL command-line utilities, you could do far worse than the $299 fully-registered version of Global Mapper.



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