The classified LiDAR data that I hope will provide some inflated structure and tree surfaces for draping the orthophoto have been reviewed. I find the data beautifully detailed, and fascinating to see with GeoCUE Point View LE. I’m working with the UC Berkeley Geospatial Imaging and Informatics Facility UCB GIIF, also known as the Maggi “Kelly Lab” when proximal to Mulford Hall.
Right now my goal is to interpolate the first return surface in a way that I can grid and filter most appropriately to inflate buildings and trees. In principle, I should be able to use the first return LiDAR point cloud to create a NURB surface that would be expressible as an OpenSim/SL sculptie. But I’m going to take a more cautious approach and try to get the whole thing gridded in a consistent way so that I can reasonably expect to cover the entire 40-region sim with good inflated surfaces rather than the bare earth that has been a fine demonstration, but a bit flat for draping the orthophoto.
I’m going to throw out a lot of images and let them speak somewhat for how the classified (into ground, structure, low veg, med. veg, tall veg) LiDAR point clouds look.
Here’s the plain elevation image and the classified view of same
this is how the classified image looks with intensity shading. It gives a first impression like a photo
Some perspective views also help to show what information will be available for gridding. For these I’ve displayed with vertical exaggeration of 1.5X
After learning how the terrain sculpties could be handled by Meshmerizer if running a physics engine like Open Dynamics Engine (ODE), I have taken a couple of weeks to proceed slowly, cautiously as I bulk up the demands on the hardware. After all, my original notion of doing large swaths of real-life terrain on a single standalone sim was based on loading that terrain into the regions then using only Basic Physics to reduce the load.
But in the months since I first started loading real terrain (starting with Mt. Tamalpais in 200710), truly phenomenal, awesome progress has been made in how efficiently OpenSim runs for me on Ubuntu/Mono. Sure, at new year 2008 my OpenSim test environment upgraded from a P3-800/1.5 GB Coppermine system to an E6550-3.4 GHz/4 GB system. But what was limiting last Fall was the chatter among the various regions, so that I could add more: 49, 81, 100 regions–but then the CPU load with no client logged in would hum up toward 70%, and running a physics engine would be a challenge with many fewer regions.
These days, that seems like a stone-age experience. The rate at which regions now load on startup is incomparably faster (even on the old Coppermine), and the chatter is almost nil–no clients logged in looks truly quiescent at 1% to 2% CPU. All this has emboldened my interest in trying ODE again. And that experience likewise is so much better. Time was, there was reason to visit the ODE site and build one’s own, and even then stuff could get strange. I was inspired by the videos that Nebadon posted showing many hundreds of blocks falling. But I experienced things like tripping over what felt like a singularity that shot my unfortunate avatar hundreds of meters into the air, bouncing like some tire that fell off of a jet after takeoff. That was then.
Now I see Ruth’s legs bend a little bit under the effects of gravity, but I do have 40 regions humming along in standalone with quiet-state CPU load of 2% to 5%. So I have plenty of reason to expect that I’ll be able to do this with the 40-region model, using terrain sculpties that are physical as long as they don’t tilt over against the terrain surface like they do in the SL Agni grid.
Video demo of Ruth narrowly avoiding getting squished by a 10-meter cube
If you’ve got the embed blocked, the link should be http://www.youtube.com/v/Jz9234jYbkw
My next goal for Open Berkurodam is to generate a new surface. I may have a good copy of what is called categorized or classified LiDAR data, where individual points in a cloud are tagged with an estimate of whether they are from bare earth, tree crown, rooftop, and such. This sort of LiDAR data should support the sort of grid that is not just bare-earth terrain, but actually has the proper size, shape, and height bump for every tree and building. This would be ideal for draping with the orthophotography, because within the limits of parallax that have been corrected in the orthoimagery, every building should sort of take shape on its own.
I don’t hold any fantasy that things will look properly immersive right on the classified LiDAR grid, but I have a sense that there will be enough detail to guide a reasonably accurate build with just a bit of training on the part of the builder to recognize their way past registration artifacts–where the bump from the LiDAR surface doesn’t align with the roof part of the orthoimage.
To bring this to a presentable stage, I hope to somehow have a live version of the 40-region UC Berkeley and vicinity 1.024:1 model with classified LiDAR surface on physical sculptie megaprims, on a public server by mid-July.
For ease of QA, there’s nothing quite like shrinking a big multi-region project to get through faster. And to share the joy a bit, this index map is in a public space, on Agni. at Amida 16/12/30
The parcel in Agni (standard Second Life public grid) now has a 1:25 model of Open Berkurodam loaded. There are 159 of the 160 terrain sculpties in place, all with full 1K x 1K ortho image textures. If you find yourself on Agni, stop by to check out the details and see the underside of the terrain sculptie diamonds.
The location is just across the water from original 1:3 scale Berkurodam BART Station. The index map can be found in Amida 16/12/30. Give it a chance to rez, because uncompressed there are 477 MB of Targa image textures represented on 159 terrain sculpties, each of which is specified with a 132×132 bumpmap. In the interest of full disclosure, I have exaggerated the Z dimension here by 50% relative to X and Y, so that the 1:25 scale is horizontal only, and vertical scale is 1:16.6 just to make the terrain more apparent. At this scale, a lot of the immersive experience seems lost and the perspective is quite a bit like Google Earth.
Striving for multiple media channels, I have also uploaded some suitably grainy videos to offer a taste to those who can’t or won’t visit the Agni grid. Believe me, it’s a much sweeter sight at 1600×1200 with the new Windlight viewer, but if one is interested in this sort of rendering, the videos might offer some motivation to explore with the SL client proper.
The longest is 3:39 and starts in Gualala, shows a bit of rezzing of the 1:25 map, does a fairly good job of showing off the texture detail on football fields, then finishes up with a flight over to the Berkurodam BART station 1:3 model, with a glimpse inside the two underground levels. http://www.youtube.com/watch?v=EjXyBWjGHA8
The next video shows some of both the 1:3 Berkurodam BART station model in Gualala, and the nearby 1:25 OpenBerkurodam index map in an adjacent part of Amida http://www.youtube.com/watch?v=-AXcDFN6LbA
There is a third one that is still uploading as of this moment
I’ve gotten into a groove with planting the terrain megaprims, and covered the eastern part of the UC Campus. I’ve also grabbed a video with FRAPS but it’s taking a while to upload to YouTube.
Things I learned tonight: it’s possible to crash OpenSim by dragging megaprims across region boundaries. The warning sign is that the prim appears to lose its name, then all prims in the region lose their names, then a check of the console will show no more OpenSim running!
After a couple of technical issues, I am pleased to offer some machinima views
This is simply how the Open Berkurodam sim looks in its overview map with 40 Regions.
I haven’t refreshed the appearence of the map since loading in the real-world terrain (20080430) http://www.youtube.com/watch?v=hvGLmtTY0uI
This is a flight eastward over some bare ground, but real-life terrain regions. Flight is in the vicinity of BANCROFT AVE between SHATTUCK AVE and TELEGRAPH AVE (20080430) http://www.youtube.com/watch?v=56PfQp9viqE
This is a flight into the land of Terrain Megaprim Sculpties. Of the three scales, this shows the medium and large steepness areas in easterly campus. At the time this was shot, there were fifteen regions with 60 megaprim sculpties in a contiguous area (20080430) http://www.youtube.com/watch?v=Q9cElvejrxo
This is a flight from the high point of the sim starting at Lawrence Berkeley National Laboratory, over the Greek Theater, and ending near Wurster Hall at UC Berkeley (20080501) http://www.youtube.com/watch?v=uBlbB72cpUQ
This is a flight starting near the old Pacific Film Archive building, through an excavation at Underhill Field that was open on 1 July 2006, then up PIEDMONT AVE to GAYLEY AVE past California Memorial Stadium and up to the far NEly corner of the sim in LBNL (20080501) http://www.youtube.com/watch?v=cealA1QL59s
Enough Videos already! While you’re at YouTube, check out “OpenSim” as a search term, if you haven’t already!
