Now, we navigate into unknown (and perhaps silly) territory. Now we do point level calculations of heights, and drop the new calculated points back into the point cloud as though it were a Z value. I don’t recommend this code as a practice– this is as much as me thinking aloud as anything Caveat emptor: Continue reading LiDAR and pointcloud extension pt 4
Digging a little deeper. Ran the chipper on a smaller number of points and then am doing a little hacking to get height per chip (if you start to get lost, go to Paul Ramsey’s tutorial). Here’s my pipeline file. Note the small chipper size– 20 points per chip. Easy enough to load (though slow for the sake of the chip size): Now we can … Continue reading LiDAR and pointcloud extension pt 3
As much for my edification as anyones: Want to get at just a few points within the pointcloud extension? A with query will get you there: Continue reading LiDAR and pointcloud extension pt 2
Paul Ramsey has a great tutorial on using the pointcloud extension with PostgreSQL / PostGIS: http://workshops.boundlessgeo.com/tutorial-lidar/ You can get point cloud and all that goodness running a variety of ways. Probably the easiest is to download OpenGeo Suite from Boundless: http://boundlessgeo.com/solutions/opengeo-suite/download/ If you are an Ubuntu user, try a docker instance to run PostGIS with PDAL, pointcloud, etc in a container: https://github.com/vpicavet/docker-pggis Also, I’m working … Continue reading LiDAR and pointcloud extension
Docker. See: https://github.com/vpicavet/docker-pggis for a quick and easy Docker running PostGIS. Understand, this isn’t production ready (the connection permissions make my teeth hurt a little) but, so nice to have a one stop shop for postgis, pgrouting, and pointcloud. Now I may have to write blog posts on pointcloud. Point cloud didn’t get in the PostGIS Cookbook because it was too hard to build. I … Continue reading The easiest way to get PostGIS and friends running:
This is starting to feel real… PostGIS Cookbook(s). 2904 pages. Page count for a single book can be calculated as in the following code: The preceding query will result in the following: A special thanks to my family, my co-authors, all the contributors to PostGIS, and to Regina Obe for helping me through the hardest bit of code in my part of the book. Check … Continue reading PostGIS Cookbook(s)
Edit: Free book to the first to tell me what the is name of the children’s book on the armchair in the foreground: Book editing in progress… . Continue reading Editing in progress
PostGIS has for a time had ST_DelaunayTriangles for Delaunay Triangulation, and since 2.1 apparently can even natively create a 2.5D TIN using said function, which is pretty cool. I think with SFCGAL, we will eventually have true 3D TINs as well. We’re still waiting on native Vororoi support for PostGIS though. According to http://trac.osgeo.org/postgis/wiki/UsersWikiPostgreSQLPostGIS “GEOS 3.5 is still in development but will have Voronoi which … Continue reading Voronoi in PostGIS
(edited: changed TIN to TIN Z) (edited again — function already exists as a flag in ST_DelaunayTriangles… .) Uh, I wrote a function for nothin’… As Regina points out in the commments, this functionality was rolled into 2.1 with a flag. Her example: For the record, my code is about 2% slower on a dataset that takes ~50minutes to triangulate . —————————————— Original Post —————————————— … Continue reading 2.5D TINs in PostGIS
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