I have in my possession four sets of shapefiles: 1. Locations (points), around 1000 2. Roads (lines), each road has a speed attribute 3. Terrain (polygons), each zone also has a speed attribute 4. Rivers (lines), each river has a crossing delay time attribute How can I construct a Voronoi diagram for my location using travel time as a distance metric? I could have used pgRouting if I had roads only, but I am not sure how to approach different off-road terrain and rivers. I'm willing to code this, but I've spent enough time trying to come up with an algorithm, but to no avail. My current plan is to dump it all into a sufficiently large raster and create 1000 distance maps out of it, then use them to calculate the Voronoi cells, but I have a suspicion that a sufficiently large raster will take too long to process. Is there a better vector-based algorithm?

SPATIQON è il GIS direttamente nel web, senza desktop: una suite geospaziale che unisce GIS, database spaziale PostGIS/pgRouting, motore QGIS, fotogrammetria da drone, nuvole di punti 3D e intelligenza artificiale geospaziale in un'unica interfaccia nel browser. Ideato e sviluppato da Sarino Alfonso

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I am using pgRouting with a street network. I added lines to the network that represent straight lines from destination points I am interested to the nearest street using ST_ShortestLine(). Now I ran pgr_nodeNetwork() to split the street network accordingly, so that it is ready for basic routing. However, when I run pgr_createTopology() the vertices are not all included to have efficient routing: select pgr_createTopology('my_table_wgs84', 0.0001, 'geom', 'street_id'); Here is a screenshot, which shows that for the highlighted red line, there are actually no vertices (red rectangles) created at all (plus you see that the connection line I created from the green destination point is actually splitted into several sublines by pgr_nodeNetwork): For the red line, for instance, the source and target is both the red rectangle you see in the bottom left. What might be the issue that pgr_createTopology don't create vertices everywhere a line ends?

Paul Ramsey has some great examples of Postgres network analysis and graph theory in this sample code for playing the Kevin Bacon game. Both pgRouting and recursive CTE are used to solve graphing rela...

Build production-grade applications with a Postgres database, Authentication, instant APIs, Realtime, Functions, Storage and Vector embeddings. Start for free.

Build production-grade applications with a Postgres database, Authentication, instant APIs, Realtime, Functions, Storage and Vector embeddings. Start for free.

Build production-grade applications with a Postgres database, Authentication, instant APIs, Realtime, Functions, Storage and Vector embeddings. Start for free.

Build production-grade applications with a Postgres database, Authentication, instant APIs, Realtime, Functions, Storage and Vector embeddings. Start for free.

Paul Ramsey has some great examples of Postgres network analysis and graph theory in this sample code for playing the Kevin Bacon game. Both pgRouting and recursive CTE are used to solve graphing relationships.

Learn how to use pgRouting as a lightweight graph database solution in Postgres.