As my patience with Second Life wanes, and I wait for more architectural input for my next SL build project, I have a dark OpenSim server with no fixed IP. I’m having stability issues with the Linux SL client, but have upgraded the workstation to Ubuntu 9.04 Jaunty Jackalope. Google Earth client there is more stable, the NVidia drivers install themselves (sans Envy), and everything Ubuntu-wise seems to be getting incrementally better by the quarter.
I’m grinding some large images that have taught me that one very special difference between Windows XP variants and Windows Server 2003 is the latter’s ability to open files on the high side of 80 GB. I’d never quite realized it before but the moderately massive mosaics that I have created in years past (edging toward 250 GB single files) actually depended on Server 2003 to get created. Once the destination file exists, then XP can take it from there, and in all cases Windows Explorer can copy the monster files. But in that tenuous moment when a mosaic first grabs its space on disk for a huge output—one can’t seem to do that with XP.
So while I’m enjoying Google Earth on Ubuntu, there is something cool that I go back to Windows for, and that’s the new Google Earth browser plug-in. Since I’m gaining a bit of facility with the keyboard shortcuts in the full-stop Earth client, these all carry over to the plugin. My first test page has been stood up here and I’ve been deep into four continents with it so far. I understand that the plugin is only available for Windows and Mac systems at this time. If you can, Enjoy!
Also, as I get even faster with my keyboard navigation of G-Earth, I’ve actually seen some artifacts that are quite familiar from OpenSim. While zipping about between the Gulf of Yakutat and Canada’s Mount Logan, at certain viewing elevations I can accelerate the point of view forward quite fast. Doing so in this very mountainous terrain, I saw blocks of terrain standing up along what look like sim edges, resolving in a few seconds as more (sculpty?) bumpmap arrives. This is the same sort of artifact I’ve seen with terrain sculpties and sometimes, with region crossings in OpenSim. Also, I’ve found a couple of wild terrain grid errors in G-Earth. In one, a quarry dug hundreds of feet below sea level, right next to the sea, is displayed as positive elevation (absolute-value terrain, anyone?). In another, a boundary between US and Canadian terrain has a glacier flowing uphill onto a plateau. Go figure. Blame Canada! ;^)
Only the four-story Administration building (wing), not the two-story Hall of Justice. I’m tired so I’ll let the shot speak for me.
photo from 2009 01 30
To me, it’s mildly amazing to realize that F.Ll.Wright’s design fits so snugly in 1/8 of a Second Life region at 1:1.00 scale. The Civic Center Administration building is a Real-Life building that can be visited, providing an easy way to get a true RL immersive sense of its scale. Building at 1:1 scale in Second Life for the first time, this has been my first experience of transferring that awareness into the multi-region contigous space of the very beautiful Second Life. Sure, I’ve built large areas at 1:1 using draped LiDAR data, but to have a rather large single building (or at least its footprint for now) in context with existing builds that I’ve seen for months, well, at the moment SL seems larger than I’d thought. That shift in my perception of SL scale may be the contrast between flying (quite fast as it turns out) around 40 to 100 OpenSim regions versus walking around the site and knowing how long it takes to traverse the RL building.
Anyway, check out the build’s progress at secondlife://Stanford/100/235/30
Today the (San Francisco) Bay Area Automated Mapping Association hosted a wonderful URISA Certified Workshop given by Tim Case, describing Best Practices and Project Implementation Methods for 3D Geospatial work. The all-day event provided a very broad and even-handed overview of many 3D technologies that hold promise for the near future.
With this presentation as an extra boost for my focus on a new build, I’m gearing up with even more enthusiasm for a new build in the Agni grid Mainland. I’ve also tuned the Berkeley parcel for sale. Its price amounts to about US$382.00, and that price is set to help cover purchase costs for the next build’s likely parcel. The tuning involved reducing the parcel size by 64 square meters, so that the three Gualala parcels total 4608 square meters, or exactly the maximum amount allowed for Linden Lab’s US$25/month tier rate. With that size, it would be possible for an interested party to purcahse the Berkeley BART station and maintain it for $300/year in tier (the Linden land property tax).
Also, based on today’s Geospatial tag, I’ve noted just this morning two mentions of the Berkeley BART build. The New World Notes item by Wagner James Au 2009 01 19 was wonderful to find after our in-world messages last month. For clarification, while true at the time of that conversation, no longer do I work for City of Berkeley. The TidalBlog item by Peter Miller mentions interesting developments in the overlap between simulators and geospatial models, as well as some shots from his visit to the Berkeley BART model. Thanks to both authors for their posts!
Silent though these pages be, much has been thought. I’ve had some quality time with inquisitive Lindens and learned to expect some sort of standalone Linden server product along about 2009. For me, that’s a game-changer as it’s hard enough to suggest (at work) creating content without also keeping up with an open source thread to stand that content up upon.
This past week I’ve made a real-life geographic shift for a family event, and learned that I’ve got a relation involved in the study of architecture. That insight has reinvigorated my interest in Jon Brouchoud and some of his writing here. The notion of architecture as it is currently an academic subject, versus architecture as a current professional practice, and the disruptive possibility of widespread virtual world deployment—this is a notion not so different from geographic science as an academic subject, GIS as a professional practice, and the possibility of immersive 3D disruption of the status quo.
Others in academic circles, including University College London, Centre for Advanced Spatial Analysis (CASA), published a Working Paper about the time this past summer when I was so focused on my 1:1 immersive build. It was gratifying to see the CASA acknowledge Second Life technology’s place in the world of neogeography and geospatial informatics.
Sitting side by side yet somehow abstracted from mapping, gaming and digital earths
is Second Life and other similar virtual environments. Second Life and their like are
easy to dismiss as pure distraction and entertainment. Yet look under the lid of
Second Life and it contains one of the most powerful geographical data visualisation
kits available
And the fine writing and attention to detail of Jon / Keystone was spotlighted in NY Times’ Style magazine this past weekend. It was a pleasure to share that link with architecture students!
It’s a big world, and immersive 3D systems must balance the tradeoff between quality and performant physics, and an economically practical level of large land areas served up to relatively sparse users, if we are to identify applications that consume vast tracts of GIS data. Spanning that scale will require that standalone Linden servers have the ability to shortcut some of HAVOK’s demands to pile in many more than four regions per physical server. After all, if I can get 100 regions stood up on a 1 GHz Celeron using OpenSim, then a four-threaded dual 64-bit Xeon server really ought to do the same for standalone Linden regions, right? I surely hope so.
I’m finding little time for keeping the OpenSim instance current. For me, there’s been a lot of problems with the more recent (last six weeks) versions simply working on first try. Also, since I have so many hours invested in the content that was created at rev 5411 that I’m a bit skittish with the bleeding edge updates.
Most recently, I’ve had the experience at osim.bargc.org of having only a single region be accessible at a time with the latest 1.21.6 SL viewer. So I vacillate between thinking “how convenient and attractive to use hosted Second Life Grid servers” and the hot-rodder thoughts “My 40-region sim is worth $7525 up front and $1610/month in tier for a nonprofit, so I can be tough.” I do tire of keeping the OpenSim server up and running with its load of content, yet with this real-world economy even avatars need to be frugal, no?
Thanks to Gualala neighbor Misty Rhodes for background
One thing about these tiny builds is that they’re easy to see from one end to the other, so why not make a video of these miniature builds in Second Life? I offer this for the amusement of Geospatial Information Service (or Geographic Information Systems if you prefer) folks who may be introducing themselves to immersive 3D. International GIS Day will be here in a couple of weeks, so I’m posting this now.
I’ve also challenged myself to improve my video production standards. Who knows, maybe more than 1300 people will view it if I make it more fun to watch with a bit of editing and title-based metadata? Nothing deep is intended with the score, it just caught my attention as matching the length of the machinima rushes tonight.
I’ve tried to improve the video with some titles to explain what’s being seen at the Level 1 (bare earth with draped ortho) 1:42-scale build, Level 2 (first-return reflective LiDAR gridded surface with draped ortho) 1:16-scale build, and Level 3 (full immersive 3D vector features in Second Life primitives with real world textures) 1:3-scale build.
If the embedded link does not work, the video is hereколи под наем which is at http://www.youtube.com/v/6joRvDH52jU
The 10th annual GIS day is arriving on 2008 11 19, and an article on the techniques that I’ve been blogging may be published on that day. In anticipation of that article, I’ve taken some time to upload selected strips of the Open Berkurodam model that has been built at 1:1.024 scale on 40 OpenSim simulator regions to Second Life. In that way, many more people may find this work and take a closer look.
In the article are three terms I’m suggesting be used for work that involves translation of GIS data into immersive 3D simulator environments: Level 1 build, Level 2 build, and Level 3 build. Level 1 is like Google Earth or MS Virtual Earth, basically bare earth gridded terrain with draped orthoimagery. Level 2 is what I’ve got as a placeholder in the Open Berkurodam 40-region 1:1-scale build, with a reflective LiDAR gridded surface draped with orthoimagery. Level 3 is just standard immersive 3D vector features that fill so much of Second Life, but in the special case of an immersive 3D build based on GIS-grade scaled mapping of building exteriors and possibly interiors.
The Level 3 build was what inspired my efforts starting back in October 2006 (Darb Dabney just has his second Rez-day celebration), but the Level 2 seems like the most important one for actual civic builds, because the grid of LiDAR data brings full-scale, full coverage data to hold the place and fill the mass of both buildings and trees, until one can afford to create the Level 3 build.
So now at the SIMGIS land in Stanford, there is both a Level 1 model (bare earth terrain with draped orthoimagery) of the entire 40-region sim at a reduced 1:42 scale, as well as a Level 2 model (gridded LiDAR first-return surface with draped orthoimagery) from the Berkeley BART station up Center Street, and on to the UC Berkeley Campus at Mulford Hall at a reduced 1:16 scale. It’s fun to see these tiny models, and it helps to convey some of the value that OpenSim offers those of us who would publish entire cities. A copy of these two models has also been placed in Amida, just across the channel from Gualala.
My selection of that path between BART and Mulford Hall was made to offer an entertaining Level 2 swath for those who would be taking transit to an ASPRS – BAAMA – GIF GIS Day event.
First the view in Second Life from Amida toward Gualala, with my Level 1 (1:42 scale), Level 2 (1:16 scale), and Level 3 (1:3 scale) (full immersive vector features with interiors) models of the downtown Berkkeley BART area. Second is the view of the SIMGIS Stanford site, with the same Level 1 (1/42-scale) and Level 2 (1/16-scale) builds.
Level 1 (1/42 scale) at base, Level 2 (1/16 scale) and Level 3 (1/3 scale) in distanceAnd here's a view of the new SIMGIS Stanford region site, as viewed from Hawthorne region. The Level 1 model 1/42-scale is just above the water, and the Level 2 model 1/16-scale is above it.
From here on the west coast of the USA, the world has seemed a bit tumultuous in the past four weeks. In a more compact and local way, this has been a time of review and reflection for me. This week I drafted an article for a local GIS Journal to review some of the explorations I’ve made since 2006 of how to create a civic-scale Mirror World. The deadline for the article has motivated me toward a bit more recapitulation on this topic than I’d expected.
My interest in the topic was first kicked off by media attention given to Linden Lab around the registration of the one-millionth resident for Second Life. I checked it out, made a rapid getaway from Orientation Island in around 30 minutes, and within a week or so the broad outlines of some intersections between GIS data and Multi-User Virtual Environments (MUVE) were taking shape in my thoughts. By Summer 2007, I’d made a fairly complex build on the mainland of the Berkeley BART station, and realized how hard it would be to justify the tier for 500 regions to host, much less build out, the entire city. But by October, I’d learned how OpenSim would solve the issue of tier, if only it were possible to make a build efficiently.
Then meshes arrived in the form of sculptie prims, and when an opportunity arose to collaborate with IBM on a multi-region terrain, I devised a way to drape orthoimagery over the region terrain. This Summer 2008 I was able to do that with LiDAR data that draped orthoimagery over terrain, buildings, and trees. The past year has been very much focused on OpenSim for me with this activity.
But behind the week-to-week excitement of OpenSim growth, and even before that, there has been a steady stream of good new stuff from Linden Lab–a stream that I haven’t reflected on so much. First off, the confluence of LibSL’s stabilization by the end of 2006, the open sourcing of the Second Life client in early 2007, and the initiation of OpenSim shortly afterward, together made possible the environment that I’m, if not taking for granted, really expecting to be there for awhile. Meanwhile, back in Second Life, there’s been integration of VoIP, new HAVOK physics, way cool Windlight enhancements to the SL client, a growth in land area that just keeps on going, plus new Openspace regions.
For reasons unrelated to my journal-article recapitulation, today I enjoyed a pleasant visit with a Linden person. It was more time to chat about civic Mirror World applications with a Linden than I’d ever had before, either in-world or real-world. In the course of our conversation, seeing the eyes of someone who is among those directly and personally impacted by OpenSim in the sense of unrealized revenue growth for Linden Lab, I gained an awareness of what is perhaps the largest contribution of Linden Lab to the OpenSim community. That would be Linden forbearance.
It’s growing late this evening for me to write much more on this right now. And as I noted, this feels like a tumultuous time for the world as viewed from west-coast USA, so I need my rest for what might be a tough week ahead. But I’ve felt a shift in perspective today, and wonder anew what the future of an operational civic Mirror World will really look like.
ABSTRACT: When creating sims based on real-world terrain, there’s usually a lot more extent and detail available than is typical when one must hand craft every region landscape. When compared with commercial multi-user virtual environment (MUVE) hosting, OpenSim has extremely low marginal cost for adding more simulator regions. Whenever a real-world region of interest has free 1/3 arc-second DEM data available for download from the USGS seamless server, then with a bit of GIS help from someone at a local university or interested government office, the free DEM data can be converted to a fine 1/10 (1:10) scale sim of terrain in OpenSim. This case study takes an idea posted to a blog, and turns it into a sim of 54-regions in OpenSim based on real-world terrain available at a 10-meter posting interval. To run all the regions, one first obtains OpenSim, then downloads the 54 terrain tiles, the 54 region definition XML files, and a loader script available from this post. The region definition files will likely need to be regenerated with the supplied PHP script to point to your machine’s IP address.
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The Case Study tour video is nearly 10 minutes, and if it doesn’t embed in your browser is here at http://www.youtube.com/v/EfBvEtTvLYU
Two days ago I was intrigued by Brian White’s posting of a Tutorial for real-world terrain in OpenSim and I followed several of his well-documented steps. Then I read all the way to the end of his posting and realized that he wasn’t fully satisfied with the results. I’ve helped a couple of folks with generating specific terrains before, and Orcas looked like an intriguing bit of topography–sort of a miniature version of how I imagine Greenland might look in, say, a couple decades…
So without an intent to cross-talk Brian’s posting, I’ll offer my own parallel perspective on how I’d approach making a recognizable, maybe even fun-to-have-around model of the Orcas Island in OpenSim. Starting from where he did, I’d like to emphasize the profound opportunities for following this approach, as it would work virtually anywhere in the continental USA (CONUS) where the 1/3 arc second seamless DEM is pretty much complete. In other words, what I’ll show here could be applied in an hour or so’s effort to produce an OpenSim version of Yosemite Valley, for example.
First, choose thy locale. The USGS seamless server is a worldwide resource, but the greatest detail available seems to be in the “lower 48″ states. A digital elevation model (DEM) with postings on 1/3 arc second interval has samples about every 10 meters in Y (north-south) and more closely spaced than that in X (east-west) everywhere off the equator. The 1/9 arc second data that Brian mentioned was actually not available for Orcas, although some urban areas may have it at this time. In this case, Orcas Island offers a nominal 10-meter DEM downloadable from seamless.usgs.gov server.
Second, define thy scale for the sim. If one will be hosting on a commercial sim, even like Linden’s Open Space sims in Second Life’s Agni grid, then there are very strong reasons to scale things down and perhaps pack everything into a single region or four. With OpenSim, unless you’re going to have tons of prims and game-grade dynamics running, it may be possible to balance the number of regions you set up with the terrain quality that you desire. For the Orcas, I downloaded the islands (using the default format which seemed to be an ESRI GRID) and explored them in ESRI ArcGIS. With that I had the sense that I wanted more or less 24 km in X, and 16 km in Y, to cover the Orcas. Since OpenSim allows me to load floating-point terrain samples on a 1 meter posting interval, I knew that my available (1/3 arc second) DEM would support a 1/10-scale sim, analogous to a 1:10 scale map. That way, I would not discard too much of the terrain information on its way into OpenSim.
Third, do the math to tile the regions. It’s not too hard, but it’s fairly unforgiving. After a bit more ArcGIS exploration, I found a way to crop the DEM to exactly 23.04 km in X, and 15.36 km in Y. Sounds wierd, or compulsively precise? Not really. Since each of my terrain samples was planned to be on a 10-meter grid interval in real-world, and my sim scale is 1/10, that means that every region would cover a 2560-meter square, or 2.56 km on a side. The dimensions that I chose were simply six regions north-south and nine regions east-west, for a total of 54 regions of 1:10 scale sim.
Fourth, get your DEM gridded. Sure, it comes from USGS that way, but the seamless server works world-wide, and that requires a geographic (Longitude / Latitude) way of defining its coordinates. To do this rigorously, I used Geographic Information Systems (GIS) software to re-project the DEM from geographic, the way it downloaded, into a projected grid [World Geodetic System 1984 (WGS84) datum, Universal Transverse Mercator (UTM) zone 10 north projection, with distances measured in meters]. The UTM grid system is defined world-wide, with the proviso that at any given spot, only one of the sixty (60) grids in the system would be the best choice. For the Orcas, it’s zone 10. For the reprojection process, I used a remote sensing package, Leica ERDAS Imagine that provides precise control over both the reprojection and the resulting data’s sampling interval. I used ERDAS Imagine to grid the UTM-projected DEM into a Cartesian grid of 10-meter interval in both X and Y, and cropped the projected data to 2304 by 1536 samples.
Fifth, dice the DEM. This is necessary for multi-region sims where your grid has more than (and exact multiples of) 256 samples in X or Y. ERDAS Imagine dices, so i used it. If you’re trying this in Photoshop, be sure to keep the pixels in 32-bit (single precision) floating point values, and don’t go to integer grayscale or the flatter terrain will get stair-step artifacts. The naming convention used in ERDAS Imagine starts at the top row and increases downward for Y, and also puts Y first then X in the tile name so that the south-westernmost of the 54 regions is called “orca_6_1″
Sixth, reflect each diced DEM tile, this reverses the direction of samples in Y dimension. What starts out as the top, northernmost row is moved into the bottom-most position, and vice-versa. This does not change the size of the tile, nor any of the gridded elevation values themselves. Another way to describe this is to flip the image around the X axis. ERDAS Imagine has a geometric correction function that allows one to specify this as an affine mapping, which I did. I’d expect that most of the world uses GIMP or Photoshop to do this, too. Although it would appear that this will scramble the terrain, it is necessary to do this to adapt the data to the sequence in which OpenSim reads the terrain file when loading it into the region.
Seventh, export the reflected DEM tiles to f32 raw binary. After trial and error, I found that using IEEE 32-bit single precision float with Motorola “swapped” byte order works for OpenSim. This is true even though my machines (both Windows and Ubuntu) are running Intel processors. Go figure.
Tenth, create a command script to load the terrain once your 54 regions are running. I include such a script that can be downloaded and invoked from the OpenSim console with “command-script terrain54.txt”.
Et Voila: A 10-minute tour of most of the sim has been recorded and is being uploaded to YouTube
