More cutting room floor stuff… .

ST_3DIntersection performs volumetric intersections for us in PostGIS, if we have SFCGAL enabled for our PostGIS back end.  Much like a normal PostGIS intersection, this is the mathematical definition of an interesection, so it returns the volumetric portion of the intersection, plus 3D linestrings and 3D points and other bits and pieces that qualify for the intersection.  As a little patch, I wrote a quick … Continue reading More cutting room floor stuff… .

O man. Epic 3D on its way. I could drone on and on about #postgis

Still working furiously on final edits for the PostGIS Cookbook.  My last chapter is the last one that the Packt editors and managers are waiting for, but it will be the best I’ve contributed to the book, so I think it will be worth everyone’s time. The trick with this chapter is that when I first wrote it, it was before the heavy lifting the … Continue reading O man. Epic 3D on its way. I could drone on and on about #postgis

Realistic biking distances, pgRouting

In an upcoming recipe (another one for the cutting room floor), we’ll play a bit with realistic biking distances, as compared with a 5-mile buffer (light grey), a 5-mile driving distance (dark grey), and a 5-mile biking-on-roads-with-speed-limits-under-40mph (purplish). This is just a teaser for mapbaker… . Continue reading Realistic biking distances, pgRouting

PostGIS Cookbook Promises

So, as we’re are in the final edits of the PostGIS Cookbook, there are some recipes that have ended up on the cutting room floor.  Several of these will end up on this blog: Amongst those that will end up in the alternate pipeline, and thus ultimately in GitHub, will be a project called pgOrthogonalize, similar to the functionality in Potlatch2 and iD to square … Continue reading PostGIS Cookbook Promises