Dan Blomberg, owner of the GPSFileDepot site, has some updates and new resources at his site:
The gSpatial Toolbar is supposedly another free option for converting shapefiles to KML format. I say supposedly because I’ve been unable to get it to work - I keep getting an ODBC driver manager error every time I try to do a conversion. I suspect you need to have Microsoft Office installed for this to work correctly; I’ve had the same error message pop up on three different computers, none with MS Office installed. But it certainly works on some computers, so you may have better luck - if so, let me know. It also requires a free registration code, which was a pain to get.
From what little I was able to see, the free version has limitations - no attribute-based KML features, and no ability to select a sub-region. Since I couldn’t get it to work, I can’t fully compare the gSpatial Toolbar to another free converter like shp2kml, but the latter definitely does work, and work well.
ht to Tim Beerman, author of the excellent (albeit not free) shapefile to KML converter, Shape2Earth.
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:
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.
A while back, I posted on the Shape Checker utility, a program that can supposedly fix damaged shapefiles. I say “supposedly” only because I haven’t been able to check it out myself, fortunately never having had that problem, but Simon Jackson in the comments says he’s used it several times successfully. I’ve found another similar tool, the Shapefile Repair Tool. It claims it will:
- Read and validate SHP and DBF files.
- Retain null shapes.
- Fix misnumbered and out of sequence SHP records.
- Correct invalid shape types.
- Correct a DBF record count mismatch is by either padding the DBF file or truncating extraneous records.
- Write a new shapefile, and a log file to document the changes.
Two caveats on my end. First off, it requires .Net 1.1 to install and run, and Microsoft in its infinite wisdom decided that Windows Vista would not support .Net 1.1. applications. So you’ll have to install it on a Windows XP system, or do without. Second, while I can vouch for the fact that it installs successfully on a Windows XP system …
…I still don’t have a bad shapefile to test it with! If you try it, and it works for you, please let me know in the comments. Thanks!
Now that TIGER has officially moved to the shapefile format, the only TIGER data left in the previous format available on the Census website is the 2006 Second Edition data, and that’s likely to disappear at some point in the future. GIS@Vassar links to an announcement at ICPSR that they have TIGER data in the original format from 1990-2006 archived for download here. Convert it to shapefile format with the free version of tgr2shp, or to KML with tgr2kml.
Over a year ago, I posted about the transition of US Census TIGER vector data from their non-standard format to shapefile format. Despite what you might have read elsewhere, the new TIGER shapefiles hadn’t been released yet … until today. They’ve been saying for months now that they expected to release them in March of 2008, and they made it just under the wire.
Via Mapperz.
“Waypoints”, geographic position markers created either in a GPS unit or using software, have been a function found on virtually every GPS unit ever made. More recently, “Points of Interest” or POIs have been implemented as an alternate way to store data for a point position, and many recent GPS units let you upload your own custom POI lists. POIs provide a handy way of organizing groups of points, and can also include more information on a point than a standard waypoint. I’ll be doing a short series of posts on creating and manipulating POIs. While the focus will be on Garmin GPS POI capabilities, other GPS manufacturers also support them as well, though usually in different formats. Note: As far as I know, only Garmin GPS units that use external data storage cards (like those listed in this post) can accept custom POI data.
Continue reading ‘Introduction To Garmin GPS Custom POI (Points Of Interest) Data’
The best way to display shapefile data in Google Earth is to convert it directly into vector KML format, and I’ve covered several ways to do that for free or cheaply, including stand-alone programs and online converters. Of all these options, I prefer using either shp2kml or Shape2Earth because of the flexibility they offer in setting display attributes like color and shape. But there’s another option: convert shapefile data into a raster image, and then display it in Google Earth as a ground overlay. This has a few advantages over vector KML format:
Continue reading ‘Using Google Earth Ground Overlays To Display Shapefile Data’
