Nearby.org.uk has a page of useful utilities for both Google Earth and Google Maps. Many are UK-oriented, but others have more general utility:
… and more. The whole site is worth poking around, especially if you’re from the UK.
Download Squad posts that Bryce 5.5, a program that creates photo-realistic landscape renderings and animation with vegetation and realistic skies, is available as a free download (registration required to get a free serial number). While it lets you create your own topography, it also accepts DEMs as input for the landscapes. This is one version below the current 6.1 release, but is still feature-rich. Unfortunately, it also has a very idiosyncratic interface that takes a lot of getting used to. Here’s a review of the program from PC Pro, with some screen shots.
There are other free programs for realistic landscape rendering, with some limitations compared to Bryce 5.5 but also somewhat easier interfaces to navigate:
Genesis IV: Available in a freeware edition for personal use, as well as several paid versions.
Terragen: The free non-commercial version limits the output resolution. There’s also a Technology Preview release of Version 2.0 available as well, though it has a fairly technical interface.
The free program 3DEM can convert a number of DEM formats to Terragen’s native terrain format, and to formats compatible with Genesis IV.
A couple of earlier posts have dealt with sites that allow you to determine a point halfway geographically between two others: a.placebetween.us and Mezzoman. Via OgleEarth comes a third: the Geographic Midpoint Calculator. Enter two or more locations, and the GMS will calculate the midpoint or average location (for more than two points). You can weight the locations by time you’ve spent in that city, though you can use the time-weight as a proxy for other weighting factors. Results are given in latitude/longitude, with the option to plot the original locations and average location in Google Maps.
Simple Spark has a searchable inventory of Web 2.0 apps, with the ability to bookmark them on-site with a free account. Enter “maps” as the search term, and 147 sites pop up, many of which I hadn’t heard of before (GPS currently only yields 4; GIS, 2).
Via Download Squad.
The Yahoo Pipes blog nominally has some examples of how to use Pipes to plot geographically-coded data in the Yahoo Maps interface using JSON and RSS (though they don’t seem to be working for me now).
Via Slashgeo.
Just a brief note to say that the open source GIS MapWindow has reached version 4.4, and the new version is definitely a worthwhile upgrade if you already have the program. A whole bunch of shapefile editing capabilities have been added, there’s now an Undo function in the shapefile editor you can turn on, higher-resolution raster export, plus bug fixes and a few other features. I plan to do a video in the near future demonstrating these new capabilities, similar to the ones I’ve done before on MapWindow.
While its primary functions deal with DEM/terrain display and analysis, MicroDEM has some handy cartographic functions as well for any position on a georeferenced map. It can calculate the amount of shift in position between different datums for both UTM and geographic coordinates; determine the current angular variation between true and magnetic north; find the deviation from true north for the UTM grid, and label sunrise/sunset/twilight times for multiple points on a map.
More after the fold …
Continue reading ‘Cartographic Utilities In MicroDEM: Datum Shift, Magnetic Declination, UTM Grid Deviation From True North, And Sunrise/Sunset/Twilight Times’
SAGA GIS (System For Automated Geoscientific Analyses) is a free raster/terrain-oriented GIS program (some vector functions), with a modular structure that makes it easy to add additional capabilities. After being in release candidate mode for about a year, the final official version 2.0.0 was released about two weeks ago, replacing the previous version 1.2 stable release. Probably the biggest change is the move from Windows-only to a multi-platform release supporting both Windows and Linux. A quick examination of the module packages shows that a few new modules have been added, but most are unchanged. However, module management has been significantly improved with the addition of a “Modules” tab to the Workspace window, and in general it’s easier to pull up data in the new version.
Best of all, there’s been a huge improvement in documentation. Version 1.2 had a good introductory 200-page manual that’s still worth downloading and reading, but many of the modules had virtually no documentation at all. Version 2.0 now has a terrific 400-page manual, available at the SourceForge download page along with a copy of the demo data used in the manual. And while even the manual doesn’t cover all the functions of the different modules, clicking on a module in the “Modules” window and then clicking on the module’s “Description” tab brings up a cursory description of the module and the input parameters. While it will still take some time to figure the module’s operation out, that’s still better than the way it was with version 1.2. A listing of the available modules is at the bottom of this post, after the fold.
It’s a good thing there are now two good manuals, because program function takes some getting used to. SAGA uses its own raster grid format (.sgrd for version 2.0), so grids in other formats have to be imported into the program (and exported into other formats as well). Setting parameters for individual data layers also takes some getting used to. But given the huge number of module functions available in this program, it’s worth spending some time figuring out how to use it. I hope to cover some of the modules not documented in the manuals in future posts (I’ve already covered using SAGA to convert raster graphics to shapefile format in this post).
A list of modules in SAGA 2.0 follows below the fold (taken from the user manual).
Continue reading ‘SAGA GIS 2.0 Released’
