Posts Tagged ‘arcgis’

VPRO: Custom Cartography and The Netherlands From Above (Stamen)

Thursday, December 1st, 2011

[Editor's note: My first big project at Stamen is live! Team includes: Geraldine, Eric, Mike, Shawn, Sean, and Zach with Jasper and Frederik at VPRO providing the data. Pretty labels powered by Dymo in zooms 7 to 10, open source auto label power!]

Republished from Stamen.

Working closely with Dutch broadcasting heavies VPRO, yesterday we launched Nederland van Boven (“Netherlands from Above”), an interactive map of the Netherlands to accompany the forthcoming broadcast of a series of shows about this fascinating tiny country. As my friend Ben Cerveny is known to say: “New York started gentrifying in the 1970s, but Amsterdam started gentrifying in the 1790s,” and the opportunity to design custom maps for a country that’s essentially all infrastructure was one that we leapt at gladly.

The show runs in a series of episodes starting later this month, each addressing a different aspect of life in Holland. It starts with mobility, answering questions like “where can I live, if I work in Amsterdam and want to be able to finish the newspaper by the time I get to work on the train?” or “How far can I travel in two hours by public transport from Vlissingen?”

Upcoming episodes will deal with other ways of looking at the environment around you: examining the natural environment by comparing distances from buildings, open space, and the density of wild animals, the landscape of danger by examining rates of lightning strikes, flammable locations and the arrival times of ambulances, and the contours of the air around the country, looking at the density of birds, flght paths of planes and the highest places in the Netherlands.

The cartography for the project is custom-made for VPRO, designed to complement the channel’s rich visual branding. Cities fill in based on a custom compilation we derived using a combination of NaturalEarthData and GeoNames sources, and and at lower zoom levels roads become visible and are drawn using data sourced from OpenStreetMap. On the most detailed zoom all roads are drawn and the arterial streets receive names. With roads come more place labels, now from OpenStreetMap and sized by population. Water bodies (black) are drawn using data from VPRO, as are park lands (black stipple pattern), airports, farm locations, pancake restaurants, neighborhood names, and zipcode shapes (the locations of pancake restaurants being as important to the Dutch as the locations of airports and farms, apparently).

The highlight layers are orange, because that’s the national color of the Netherlands. Also, did you know that carrots are orange because that’s the national color of the Netherlands; “in the 17th century, Dutch growers are thought to have cultivated orange carrots as a tribute to William of Orange – who led the the struggle for Dutch independence.” So: orange maps over custom OpenStreetMap cartography, a client who wanted to tell a story and was willing to stretch what it means to design a map, and a country made of canals and land claimed from the sea. Hoera!

Technical bits:

We used open source software, some authored by Stamen, to draw the reference cartography and cache the data files. Web maps are made of small, 256 px by 256 px images, stacked next to each other in a grid and displayed in the browser as a slippy map, allowing the user to pan and zoom. The application logic in Flash allows us to speedily update the map (using the GPU) when the data filters are adjusted. Software utilized includes TileStache, Cascadenik, Dymo, ModestMaps, Mapnik, QGIS, OGR, and GDAL. Much of the data provided by VPRO was generated in ArcGIS in-house and and partners. The place search is powered by the Yahoo! geocoder.

Interact with project »

The ESRI UC ArcGIS 10 Q&A Response Is Up (James Fee)

Friday, July 9th, 2010

jmf-where20-2009-sidebar[Editor's note: As the GIS community prepares for the just released ArcGIS 10 and gathers for the annual User Conference in San Diego, Ezree cum E.S.R.I. has posted a Question and Answer FAQ about the new release. Notable to me: Visual Basic for Applications (VBA) is resurrected for the last time, time to learn Python! James Fee translates from corporate speak.]

Republished from Spatially Adjusted.

One of the best insights into ESRI and their direction is the UC Q&A. ESRI has posted the latest one here and some highlights are below:

Q: What has ESRI done in the area of map books?

A: At ArcGIS 10, functionality has been added to allow you to create map books using a feature layer to define map extents for multiple pages. This new functionality, in conjunction with all the other enhancements to support map books, is referred to as data driven pages. Data driven pages give you the ability to generate multiple pages by taking a single layout and iterating over a set of map extents. Any feature layer, point, line or polygon can be used, along with a margin, to define the extents.

A question I still get asked again and again is when is ESRI going to update DS Mapbook. Well now you’ve got a real solution built into ArcGIS 10.

Q: Does ArcGIS 10 open up more functionality for use with Python?

A: Python integration is one of the key features of ArcGIS 10. At this release we’ve introduced a new Python subsystem called ArcPy, which exposes many of the ArcGIS functions.

ArcPy is still a little kludgy, but wasn’t isn’t with ArcGIS 10.

Continue reading at Spatially Adjusted . . .

Review of new tome for map projections: Lining Up Data in ArcGIS (Vector One)

Thursday, June 24th, 2010

lining-up-data-sm[Editor's note: No PRJ file? No problem. Use this new guide by M. Maher from ESRI Press to learn map projection basics and the ArcGIS commands (versions 9 and 10) that register map data to common coordinate spaces. Read the first chapter and table of contents at ESRI.]

Republished from Vector One.

Lining Up Data in ArcGIS – a guide to map projections is a new book from ESRI Press. It is authored by Margaret M. Maher. Since I don’t have ArcGIS running in my office I couldn’t try out some of the details provided in the book, nevertheless, I did spend some time running through the book and offer the following comments.

One of the issues that many people encounter with GIS data revolves around projections, coordinates and lining up data with already existing spatial information. I’ve made the mistake myself numerous times, excited to get the data into the system, only to open the map window and finding what I just added from Berlin is placed in Oklahoma, Alberta or the middle of the Mediterranean Sea. How did that happen? Because I never lined up the data properly.

This book is very helpful. It explains how to identify geographic coordinate systems as compared to projected coordinate systems. If you are using ArcMap, then this book will show exactly how to determinine projections and set them. It even provides examples for going to ArcGIS Online, downloading imagery and aligning it properly.

Continue reading at Vector One . . .

Review: Geocart 3 (Kelso)

Friday, May 14th, 2010


Once a required computer application in many cartography shops in the 1990s, Geocart has come back with a vengeance with Mapthematic’s 3.0 release (Mac and now Windows).

“If map projections are your problem, Geocart is your solution”

While most GIS and remote sensing map software support a couple dozen obligatory projections, Geocart supports over 175 general case projections. Map projections are mathematical formulas for converting the earth’s round shape to a flat surface and their “parameters” can be adjusted to form thousands of specific projections. For comparison, ArcGIS, the popular commercial geographic information system software from E.S.R.I. supports 1/3 as many projections; MaPublisher from Avenza supports 1/2 as many as Geocart.

The program’s author, daan Strebe, is a leading authority in this specialized subject and the new version incorporates corrections to many standard formula resulting in near loss-less projections. Unlike other software packages, Geocart can transform any projection to another projection (full forward and inverse transformation support for all projections). Other map applications can damage data when it is transformed. Furthermore, Geocart 3 introduces a new rendering mode using PixSlice technology to create a sharper, more detailed raster images (examples after the jump). This works both for resizing images and when transforming from one projection to another (reprojecting).

The application manual includes a handy decision tree to assist in what projection to use depending on the map’s topic and geographic coverage. The application includes innovative advanced tools  to visualize the distortion inherent in each projection (sample image).

Pricing: For lapsed users, upgrade pricing is available for $500 with new professional licenses running $860, discount for multiple purchases. Steeply discounted non-commercial and student licenses are available. Price includes map databases (36GB with the pro version!) and, importantly, the new version imports shapefiles, the defacto geodata format.

Full review continued below . . .



I tested Geocart using the free, month-long trial (note the watermarks in the screenshots). Download and installation (once for the application, again for the default databases) went quickly but you will need an administrator account to accomplish the install. When the package downloads, it is labeled with your operating system type rather than “Geocart” so in my case I looked for “Mac OS 10.5/10.6″ in my downloads.

The app and included databases each weigh in about 150 mb for 300 Mb of disk space. Rather than collecting associated database files in the Applications folder (Program Files on Windows), they are installed in Library > Application Support > Mapthematics > Databases. If you want quick “template” access to frequently used data, it should be added in that location. The “add recent databases” command partly makes up for this.

Setting up a map document

To start mapping, go to File > New. Then go to Map > New. Multiple maps can be stored in a single Geocart document, each having their own projection parameters and database content.

When making a map, the first step is to determine how large the map dimensions will be and how much geography it will show. The relationship between the two is called map scale. Some databases, like Natural Earth, are set up based on map scales. Using the right database will result in prettier maps that are generalized appropriately (the linework doesn’t look too detailed or too coarse) and smaller files that are easier to work with.

Geocart also includes a useful linework simplification routine when your data is complex and needs to be simplified. This toggle is on by default and is accessed under Map > Generalize vectors. Toggle it on and off to compare the resulting resulting lines, your mileage will vary by map scale, even with the same source database.

Tip: The application takes map scale seriously and includes a tool to calibrate your system under Preferences > Display. This calibration functionality is absent to most other mapping packages.

To add data to the map

Each new map starts with “Stylized World Topo 5400×2700″ raster image in layered with a vector grid (Map > Graticule) in sinusoidal projection. With the map selected, go to Map > Databases. I was able to easily add in shapefiles from Natural Earth, some of which are included in the default databases. If you have existing Geocart 2 format databases, those will import directly, including typesetting databases.

Tip: To modify which databases load for each new map, go to Preferences > New Map Databases. I set mine to use Natural Earth country boundaries but removed the default image database.

Have a scanned map without a projection?

Geocart will help you figure it out. Add the map with File > Place image. (Vectors are not supported at this time). Then align with a map with a vector map database. Adjust the settings of the map until it matches. Then choose File > Export Database. Load the database back into a Geocart map and start projecting.

I was also able to add several map images and quickly georeference them and then deproject to geographic (platte carrée) or into another projection. One was a simple map of the ash plume in Europe in Mercator. The other was a complicated world wall map from National Geographic in Winkle Tripel (examples below).

Tip: When georeferencing an image, maximize both the map and the placed image to fit the window (Map > Scale to Window). Then adjust your Geocart map to use the same boundaries as the placed map image (make an educated guess). Then cycle thru the projections until the vector lines (graticule and country boundaries, etc) begin to match. Mercator and Robinson are common for world maps, a conic like Albers or Lambert is common for country and state maps. Then adjust the projection parameters and fine tune the boundaries and nominal scale and map resolution till everything fits exactly. Finally, export the placed image to database format.

Note: For raster maps that are georeferenced, the exported database file remains in the native projection of the image (it it not transformed to geographic). This does not affect your ability to reproject the image, however

Choose a projection

The familiar icons by projection class are still found in the main menu bar (see screenshot above). With a map selected on the document, choose a different projection (some are even listed in cyrilic and arabic!) and watch the map update in real time.

If you want assistance in choosing a projection (who can remember all their quirks!?), check out Projection > Change Projection. A dialog with the same listing comes up but with descriptions, history, preview maps, and distortion information. Gain insight with the programmer’s unique and comprehensive expert knowledge will help guide your projection choice. While the map is projecting, a progress wheel with a rough remaining time will show in the upper left corner. Advanced datum support and transformation are provided.

Tip: The manual includes a full decision tree for choosing a projection. This is one of the best features of Geocart.

I love interrupted projections like the Goode homolosine and making one in Geocart is a cinch. Simply choose the Goode from the Pseudocylindric menu (oval icon on left) and then chose Projection > Interruptions > Goode Continental. While you’re getting the projection parameters, map size and resolution right, keep the rendering quality at draft (Map > Draft). When the settings are right, change that to Map > Final Quality for more precise results.

All databases in Geocart are geographic with live, on-the-fly transformations into your map’s specified projecting (see exception above for georeferenced images). I added in coastlines, rivers, lakes, country boundaries, US state boundaries into my test vector map. Even on my slowest, older laptop, rendering was responsive for basic usage creating vector world, regional, and country maps.

Tip: If you somehow end up with a strange looking map (off center, etc), choose Projection > Reset Projection and the current projection parameters will revert to defaults

Tip: When using a conic projection like Albers or Lambert, make sure the Projection > Projection Center is set to Latitudinal 0°N.

Geocart 3.0 is a world unto itself, however. While it does import raw data in shapefile format (YES!), it does not currently import or export PRJ files, part of the SHP file specification, the defacto geo data storage and exchange format. Imported SHP files must be in geographic projection. This makes sense in part as Geocart supports many more projections and parameters than most other mapping software packages (3 times as many as ArcMap, 6 times as many as Natural Scene Designer, 2 times as many as MaPublisher and Geographic Imager). Geocart also sometimes uses slightly different formulas for the same projections as the other applications (the author claims Geocart’s implementations fix errors in common formulas, which is probably the case based on my experience with the literature and web source code snippits).

But for the projections that are shared in common, it would be useful to offer PRJ support (including transformations out of the error prone versions), and shapefile export of databases after their coordinates have been transformed (and GeoTIFF for raster).

More importantly, PRJ files offer a quick load of common projection parameters. So if I’m in California I can load up the Albers with the standardized parameters so my data will interoperate with other cartographers working in that area, and they take some of the guess work out of choosing a map projection. Both ArcMap and MaPublisher are better then Geocart in this regard. MapTiler thru Proj4 is the worst. Azimuth (r.i.p.) is the best at setting appropriate projection and parameter for the visible, selected geography.

Tip: If you do have a PRJ file, open it in a text editor and manually copy over the parameters to Geocart. They use a “well known text” structure that is human readable.

Legend editor (stylizing your map)

Geocart includes basic legend editor for setting line and fill styles, appropriate for general reference mapping. Geocart is a general projection tool, not for making thematic maps. The layer sorting of individual databases is adjustable in the Map > Databases dialog.

Tip: Consistent styles can be shared between map projects by going to Preferences > New Map Line Styles.

Testing the limits

Don’t want to plot the entire world? Use Map > Boundaries to set a crop (and speed up map rendering). This window is quite amazing and has both 2d and 3d views with actual spherical trapezoids! Boundaries can be set relative to the projection center and can be a circular diameter, spherical trapezoid, or irregularly shaped “custom” boundary. To remove the boundaries, change the setting back to “Unconstrained”.

Quibble: When adjusting boundaries in most conic projection, your standard parallels should also change. A prompt should be provided in this use case to automatically adjust those to your new view. In the special case of setting standard parallels in Projection > Parameters, it would be helpful if Geocart showed these on a map like in the Projection Center dialog.

Quibble: The draw on map interface in Boundaries needs a little more work for modifying the existing settings. Other apps, like Geographic Imager, allow me to drag the edges of a drawn boundary while in Geocart I have to start over (or use the number fields). It’s also a little wonky when dragging exactly horizontal or vertical (a full latitude or longitude strip). There are also no ticker buttons to increment the parameter values, either. Once you have this set, though, you’re golden so it’s a minor inconvenience.

Next: Rendering quality and speed . . .


Above: Brand X on the left. Geocart at right. Examine the letter forms (U in United Kingdom, N in London, all in Paris, the Ca in Cariff). The Geocart render results in sharper, crisper letter forms with less “pixel burrs”. The demo water mark not with standing.

Rendering quality

The key concept is Geocart creates an optimized map on each render. The original data resolution is stored in the document, but what draws on the screen is determined by the map size and resolution. Set that in Map > Set size and resolution. Once adjusted, the map will fill that space in the window. You can zoom in and out with the normal Cmd-+ and – keyboard shortcuts and the zoom with update in the window title.

When Geocart is set to render in Final mode, its output results in better output than applications that use only nearest neighbor or bicubic interpolation. In the example above, looking at the letter edges on London, the Geocart version is crisper and smoother. This also comes into play at the edges of a world map where the projection distortion is more extreme and is especially important with projecting raster data.

For my heavy-use scenario, I put Geocart up against the latest National Geographic world map

The map is in Winkel Tripel projection. I rasterized the PDF (took about 1 hour with Photoshop on my old laptop) and then loaded the image into Geocart and georeferenced it and saved it out as a database (78 mb, seems small), see section on Adding map data above. I then reprojected it Goode homolosine in Geocart. I also ripped out a platte carrée from Geocart and projected that into Goode in Geographic Imager, Natural Scene Designer, MapTiler (Proj4), and ArcMap.

The final projected Goode image dimensions was 22,700 pixels by 9,910 at 675 mb in TIFF image format. Enough detail to print back out as a wall map or tile for a web map service.

Geocart is built for speed and will utilize all processors, including multicore

Paul Messmer’s under the hood improvements allow the application to make 100% use of all processor cores. I was still able to use other applications while Geocart processed data, however. One side effect of supporting multiple cores is rendering occurs per core in real time, see screenshot below. Geocart also plays nice on idle.


I tested Geocart on 3 different machines, all Intel Macs running 10.5 or 10.6 from an older laptop to a new desktop towers. Application task completion speed increased directly proportional to the number of cores available.

Fun fact: Geocart uses a Hilbert curve to render the map when utilizing multiple cores to keep memory accesses as local as possible in order to make the best use of the processor caches. This results in seperate render traces on the screen, see image below.


At best “final” settings, the huge map in Goode homolosine projection described above took 20 min on the 16 core Mac Pro (2 x 2.93 quad core GHz quad-core Intel Xeon with 8 gb of RAM) but 1 hour 20 minutes on an older 4 core Mac Pro with the same RAM configuration. The draft render took significantly less time and was comparable in time and quality to Natural Scene Designer, Geographic Imager, ArcMap, and MapTiler (Proj4).

Because Geocart is always planning for the most general case with the most advanced options, this can slow down it’s rendering compared to other applications (most noticeable when in Final rendering mode). Future versions might speed up if special functions were added for the standard parameter cases. But by the time the programmer did that, the speed difference might be equivalent to increases in hardware speed and cores, so this doesn’t worry me much.

Compared the competition

Geographic Imager ($699 for Adobe Photoshop plugin, add $699 if you don’t already own Photoshop) did not support the interrupted form of the projection and produced confetti until I tweeked the settings. To project vectors, you’d need MaPublisher, a vector plugin from Avenza for Adobe Illustrator, will set you back $1399 plus cost for Illustrator. ArcMap (thousands of dollars) required a RGB (not indexed) version of the geographic TIFF version but insisted on reprojecting into grayscale. Natural Scene Designer ($160) produced the most comparable raster results and ease of use, but at less quality (though faster). It should be noted the Pro version of Natural Scene Designer 5 also supports multiple cores and limited vector shapefile support (raster rendering only), plus better handling of GeoTIFF with TFW export. MapTiler, Mapnik, and other open source GIS options are free but you’ll spend time setting them up and learning their make-by-and-for-programmer quirks.

Visualizing Distortion

Geocart is a good teaching tool as well when using the distortion visualizations and mouseOver readouts (available under Window > Information). The pertinent readouts are Angular deformation, Areal inflation, Scaler distortion, and Scale factor range.

Note: Geocart quit on me once when I tried to use Map > Copy Attributes while visualizing distortion with a very large selected map, but I was not able to replicate the error or any crash in subsequent testing sessions. In general I’ve found the program to be very responsive and to not hang up, even when rendering extremely large maps with multiple databases.

Quibble: The Information panel should display how long it took to render the selected map.


On exporting out your final map, vector (PDF) and raster (TIFF, PSB “Photoshop”, and JPG) formats are available. On opening the map in Illustrator, each database layer is conveniently grouped, with clipped content. Geocart could take a page out of IndieMapper’s layered SVG approach where the file format would still be PDF but the groups would be named and even better yet actual PDF layers.

Quibbles: Geocart suffers from the same zealous masking and embedding as other apps. If no boundaries have been defined in Geocart, the clipping masks should not be included. Saving out as PDF will embed the raster databases into the file, like all other programs. On export of the raster formats, an option should be provided to NOT export the vector database layers. Another option should be provided to export each raster database layer to a separate file (or layered TIFF / PSB). Needs to export out a PRJ file for the raster and GeoTIFF with embedded registration, pixel size, and projection tags.

Note: If you’re looking for SHP export, you’ll be disappointed. Though that’s kind of missing the point of Geocart. See “Choose a projection” section above.

Final word

Geocart 3 is a solid release that will satisfy most of your reference mapping needs, especially if projection matters to you. If you liked Geocart 2, you’ll definitely enjoy working with version 3, and on the latest computer hardware it simply screams. The addition of direct shapefile import removes a barrier to geodata access, though more could be made of the PRJ files and DBF attributes. There are still some missing features when compared to version 2 and daan (the programmer) is interested in hearing from the cartography community which should added back. They also seem responsive to fixing some of the usability issues I’ve noted above.

But where are those Kelso Corners, I ask? Besides being a personal soapbox, my blog is named for the “corners” that form when a pseudocylindric or lenticular projection is extended to fill out it’s rectangular bounding box by repeating content that would otherwise only be found on the opposite edge of the map. They are righteously awesome, plus they satisfy non-carto designers  proclivity to design to a boxy grid. However, you can only find these “corners” on a few old print maps; I don’t know of a single digital app that creates them. I’ve staked naming rights ;)

Pros: Over 175 projections (best in industry), support for advanced projection parameters, loss-less reprojection, PixSlice technology for sharper, more detailed raster images. Runs on both Windows and Mac, with support for multiple core processors. Now imports shapefile vector map data. Large document support. Easy to use. Software programmer responsive to emails and forum posts.

Cons: No PRJ support. Does not export GeoTIFF, or world file created after georeferencing images. Does not include a SHP filter in file dialogs, and file dialogs do not remember last browsed directory. Should start with blank new document on launch. Linework generalization engine filters just by Douglas-Peucker in this version, not the smooth bezier curves found in Geocart 2 or the amazing generalization found at Rendering in PixSlice can significantly increase render times. No support for scripting/automation. No export back to SHP format (especially with DBF attributes), useful for thematic mapping in a secondary GIS application.

ColorBrewer in ArcMap, updated to version 2.0 (via Weary Ramblings)

Tuesday, March 16th, 2010


[Editor's note: Struggling to pick colors in ArcMap or need to ensure your design meets federal accessibility standards for vision impairment? has been updated to version 2.0 and now a ArcMap plugin brings some functionality right into your GIS. It's not clear to me if the "Terrain overlay" option for previewing the colors takes into account the muted nature / secondary HSV mixing of the colors, I don't recommend using that part just yet.]

Republished from National Cancer Institute.
Seen at Weary Ramblings.

ColorTool is a plugin for ArcMap™ (part of the ESRI ArcGIS Desktop suite) that helps users create choropleth maps using ColorBrewer color ramps.

The program runs from a button in the toolbar and opens a form that guides the user in choosing a classification scheme. For more information on the color options, visit ColorTool supports Quantile, Equal Interval, Natural Breaks (Jenks), and Unique Value classification types.

Download the ColorTool plugin . . .

Along with the plugin, the main ColorBrewer site has been upgraded to version 2.0

Republished from Free Geography Tools.

ColorBrewer is an online Flash app designed to help select appropriate data coloring schemes for maps, including sequential (choropleths), diverging (data with break points), and qualitative (discrete categorical data). I’ve covered version 1.0 before, and now ColorBrewer 2.0 is out. Not a huge number of functional differences, but some useful additions (and one disappointing subtraction):

  • More parameters are selected by drop-down boxes instead of buttons; bit faster this way
  • All controls are on the left side, making them easier to find
  • You can now choose between a colored background and a terrain background
  • Color transparency can now be set between 0 and 100%
  • More choices for background, road, city and border colors
  • You can now screen color schemes by appropriateness for color blindness, photocopying and print. In version 1.0, you only had icons showing which uses were appropriate, and these are still available in the “Score Card” tab at lower right
  • More options for color scheme export directly from the program, including an Excel file of all available color schemes, export in Adobe Swatch Exchange format (ASE), and in-program text hex color codes for copying and pasting into graphics programs.
  • No more map zoom; I miss this option.

What is GeoDesign and why is it important (ESRI + GeoInformatics)

Monday, March 15th, 2010

[Editor's note: Like mashups, but in ArcGIS and analytical without programming skills. Sounds like CommunityViz but is more generally the "pairing of design and GIS. It unites the art and creativity of design (planning) with the power and science of geospatial technology. As one, GeoDesign can produce more informed, data-based design options and decisions." This drive will introduce modeling, sketching, and feedback capabilities in ESRI's ArcGIS Desktop 10, set for release in the second quarter of 2010. Looks like it will rely more on GIS services (web apps and 2) and more validating of resulting feature topology by GIS techs. Recently concluded mini-conference on GeoDesign has streaming video clips. This article is also good. Thanks @geoparadigm and @gisuser.]

Republished from ESRI and GEO Informatics.

What is GeoDesign?
GeoDesign is a set of techniques and enabling technologies for planning built and natural environments in an integrated process, including project conceptualization, analysis, design specification, stakeholder participation and collaboration, design creation, simulation, and evaluation (among other stages). “GeoDesign is a design and planning method which tightly couples the creation of design proposals with impact simulations informed by geographic contexts.” [1] Nascent geodesign technology extends geographic information systems so that in addition to analyzing existing environments and geodata, users can synthesize new environments and modify geodata. Learn more about GeoDesign on Wikipedia.

Read more at ESRI ArcWatch . . .

Jack Dangermond on GeoDesign:
“In January [ESRI hosted] the first GeoDesign Summit. It will bring people from both the GIS and design fields together and have them share their work and get a conversation going. I’m not totally sure what the outcome is going to be, but I’m hoping a new profession or direction will emerge. I think we need this kind of mixing at this point to bring these two fields together; people who design the world with people who design the future. Today, geography lives very well in its world and designers live very well in their world, but there’s not this cross-mixing. I believe the outcome will be much enlightened ways to do development; ways that bring science into how we design things: cities, the environment, highways, everything that we do. Today we certainly see the need for this all the way from global warming to designing more livable and sustainable cities. We need more geographic thinking in the way we make decisions. GeoDesign is an attempt to try to do something about that.”

Read more at GEO Informatics . . .

What does it mean for GIS discipline:
“It is not so much that geodesign is new, but rather that technology has reached a point that allows artists to participate in the geodesign process – without becoming technologists.” (Kirk at GeoThought) It still requires good (accurate, precise) base maps and themes in GIS to enable smart decision making (geodesign) on the desktop and in the cloud (web apps). Instead GIS techs being puck jockeys, the planning folks will be able to use the GIS directly, or it’ll seem that way to them ;) I used to work somewhere where the boss had desktop design apps installed and he could comp out designs, but they still had to be rebuilt to production specs. My guess is the same will be true with GeoDesign for a good bit yet. Meanwhile, focus on core competencies.

Learn more at the ESRI Developers User Conference later this month . . .

Time Awareness in ArcGIS 9.4 Leads to Better Understanding of Complex Geographies (ESRI)

Thursday, January 7th, 2010

[Editor's note: In the next release of ArcMap, due this summer, ESRI takes cues from Google Earth and adds a "time slider" to easily visualize time series in GIS.]

Republished from ArcNews (Winter 2009/2010).

Visualizing Time in GIS

In his First Law of Geography, noted geographer and cartographer Waldo Tobler states, “Everything is related to everything else, but near things are more related than distant things.”

GIS professionals are well versed in visualization of spatial relationships and dependencies, of the proximity of near things and distant things, as in things you can measure with a ruler or with mile markers. But often when studying geography and looking for relationships and dependencies, equally important is proximity in time, as in something that can be measured with a watch or calendar.

click to enlarge
You can control visualization of temporal data in ArcGIS 9.4 using the new “time slider.”

Pioneering environmental planner Ian McHarg is widely known in the GIS community as the “discoverer” of overlay theory, the base theory behind GIS. Another of McHarg’s discoveries—perhaps lesser known, but equally important—is chronology, or the placing of geographic layers in chronological sequence to show relationships, dependencies, and causation through time. “We found the earliest events, mainly of geological history, had pervasive and influential effects, not only on physiography, soils, and vegetation, but also on the availability of resources,” McHarg states, describing an environmental planning study in the 1960s, in A Quest for Life. He calls his discovery of chronology—the order or sequence of features through time—”. . . a most revelatory instrument for understanding the environment, diagnosing, and prescribing,” a construct that leads to a deeper understanding of structure and meaning in the landscape.

click to enlarge
Charles Joseph Minard’s 1869 flow map of Napoleon’s 1812 Russian campaign is a classic example of spatiotemporal visualization (Image Source: Wikimedia Commons).

Chronology is enabled by temporal data. Temporal data is data that specifically refers to times or dates. Temporal data may refer to discrete events, such as lightning strikes; moving objects, such as trains; or repeated observations, such as counts from traffic sensors.

Depicting spatial change over time is a four-dimensional problem, and visualizing temporal phenomena on a two-dimensional map has always been a challenge. The simplest approach is the map series, where individual maps of geographic conditions at certain points in time are presented individually, in chronological order.

Other inventive methods of visualizing change over time and space include creative symbolization, such as in Charles Joseph Minard’s famous map of Napoleon’s march across Russia.

Temporal GIS is an emerging capability for integrating temporal data with location and attribute data, enabling temporal visualization and ultimately temporal analysis. Visualizing change on a computer screen in a GIS environment may give the viewer more options, but it is still a challenge. A simple yet highly effective method of visualizing time in GIS is through animation—displaying a series of maps in rapid succession on the screen.

click to enlarge
A creative method of representing temporal datasets in GIS developed by the Earth and Environmental Science Division at Los Alamos National Laboratory (ESRI Map Book, Volume 19).

“The eye and brain are enormously efficient at detecting patterns and finding anomalies in maps and other visual displays,” says Michael Goodchild of the University of California, Santa Barbara. “GIS works best when the computer and the brain combine forces and when GIS is used to augment human intuition by manipulating and displaying data in ways that reveal things that would otherwise be invisible.” Building a robust temporal capability into GIS provides the human eye and brain with powerful visual tools to help determine the reasons why things happened in space-time. It is also key to modeling and predicting things that might happen in the future.

The new time-aware functionality in ArcGIS 9.4 lets you

  • Create and manage time-based data.
  • Display and animate temporal datasets.
  • Publish and query temporal map services.

click to enlarge
The user interface in ArcGIS 9.4 lets you set time properties for one or more layers.

ArcGIS 9.4 makes temporal mapping simple and easy; enables temporal data management, exploration, and visualization; and creates a strong foundation upon which sophisticated temporal geoprocessing tools and workflows can be built in the future. As McHarg states in To Heal the Earth, “Processes, laws, and time reveal the present.” And once we have the tools and techniques in place to fully grasp how the past has created the present, we can use these same tools and techniques to shape our future.

More Information

For more information, visit

SatValMod Color-Greyscale image integration (Viljoen via ESRI)

Wednesday, October 28th, 2009


[Editor's note: This VisualBasic script from David Viljoen, Geological Survey of Canada, for ArcGIS solves a transparency flattening issue when trying to blend color into a grayscale shaded relief image. Often the colors become distorted during the merge. This tool preserves the color (hue) and moderates the saturation and value instead. I've used HSV color adjustment layers in Photoshop with relief masks to accomplish the same thing, nice to know it's available in ArcMap, too. Aileen mentioned it at NACIS Sacramento earlier this month.]

Republished from ESRI.
By David Viljoen.

I developed the SatValMod (SVM) method to address the problems associated with traditional methods of integrating color with gray-scale raster data (e.g. layer transparency, multiplying color by gray-scale values, etc.).

The main problem with traditional methods is color loss or corruption. SVM does not change the original hue and modulates the saturation and value so that the final output has the same rich colors of your input data.

SVM does not require Spatial Analyst. It supports Grid, BIL, and TIF formats for input. It outputs a BIL file.

The SVM method involves a pixel-by-pixel transformation of RGB color coordinates to HSV space, modulation of the saturation and value color components, and transformation of the orginal hue and modulated saturation and value components back to RGB space. More details are available in the PowerPoint slide show included in the ZIP.

This technique can work with rasterized polygon layers. You will need to create a CLR file that relates pixel values to the polygon colors.

I hope you find SVM useful in creating your color/gray-scale image integration products.

Download from ESRI . . .



Embeddable US Demographics Map (ESRI via FreeGeoTools)

Thursday, October 22nd, 2009

[Editor's note: This was demo'd at NACIS earlier this month. Raster thematic map tiles delivered via Flash API that are still interactive. ESRI's solution to Google mashups.]

Republished from Free Geography Tools.

As a demo of the ArcGIS API for Flex, ESRI has a new page that lets you create an embeddable/shareable map of demographic data by US county. Only seven datasets available now:

  • Median Household Income
  • Population Change 2000-2009
  • Population Density (per sq. mile)
  • Median Home Value
  • Unemployment Rate
  • Average Household Size
  • Median Age

Map creation is trivially easy – select the demographic dataset from a dropdown, zoom the map to the desired extents, set a map size in pixels, and you’re done; links to a map with your parameters, and code for an embeddable map, are generated automatically. Here’s an embedded map, scrollable and zoomable; unemployment rate is the default dataset, but you can choose other sets with the dropdown menu at upper right:

More datasets would be nice, as would control over colors and ranges …

Interact with the original at Free Geography Tools . . .


Problems Dissolving in ArcMap, Try Repairing Geometry First

Tuesday, July 14th, 2009

[Editor's note: I was having trouble last week dissolving a shapefile based on a common attribute. I kept getting the following error: "Invalid Topology [INCOMPLETE_VOID_POLY]“. Not entirely helpful! A little Google searching turned up the following tip from ESRI.]

Republished from ESRI.

Problem:  Some Overlay Tools, such as Intersect, return unexpected results or fail


Results do not look correct or operations fail with strange errors such as:

“Invalid Topology [INCOMPLETE_VOID_POLY]“.

If this type of error has occurred, it is most likely to occur when using one of the following:
Clip, Erase, Identity, Intersect, Symmetrical Difference, Union, Update, Split Featureclass to Coverage, Dissolve, Feature to Line, Feature To Polygon, Integrate, or ValidateTopology.


It is possible that tool outputs may be strange or incorrect because one or more features in the input feature class have geometry problems. Some examples of geometry problems are:

· short segments
· null geometry
· incorrect ring ordering
· incorrect segment orientation
· unclosed rings
· self-intersections or empty parts

Solution or Workaround

If such errors occur or the output looks incorrect, the first step in assessing the situation is to run the ArcToolbox tool Data Management Tools > Features > Check Geometry. -show me

[O-Image] Check Geometry

This tool provides a list of the invalid features in the feature class and a short description of the problem. Features with problems can be fixed in one of two ways:

  • Editing the feature class with the geometry problem, and fixing each individual problem identified. Some of these problems, like non-simple geometry, can be fixed by double-clicking the feature in the editor and saving the edits.
  • Running the ArcToolBox tool Data Management Tools > Features > Repair Geometry on the feature class containing the problem features. -show me