I am a professional traffic engineer and I build micro-simulation models for most of the projects I am involved with. I can say that compared to software that is used in industry (PTV Vissim, PTV Vistro, and Trafficware Synchro) it looks like A/B is a reasonable toy model that can get pretty close to the real thing. I think it is great that software exists at a level for individuals without huge budgets to be able to build and play around with traffic networks. Automating the intersection setup goes a long way toward this type of tool being accessible to the lay person. All that being said, I think the limitations of any model are important to understand when interpreting the outputs. I can take any model and make traffic flow or decrease the delay per vehicle, that doesn't mean my results are realistic.<p>Keep up the work, this is an awesome tool and I hope it can get to the point where it can easily help inform people about traffic design and simulation.
A/B Street is an open-source traffic simulator that lets you edit roads and intersections, based on OpenStreetMap data. But to even do that, first we have to geometrically represent the transportation network in great detail. This is a second deep-dive into how things work.
You can play it right in your browser: <a href="http://play.abstreet.org/0.2.58/abstreet.html" rel="nofollow">http://play.abstreet.org/0.2.58/abstreet.html</a> What a cool project!
Years back as OSM was fading and the v1.0 of mapbox started rolling out my pedestrian view of the space was that we were seeing the endgame unfold<p>It's insane to see the levels of depth still to plunge - this is incredible documentation and a very cool project<p>PS - I'd upvote twice if I could for incorporate of cthulhu mythos!
> Highway on/off ramps <a href="https://a-b-street.github.io/docs/tech/map/geometry/index.html#highway-onoff-ramps" rel="nofollow">https://a-b-street.github.io/docs/tech/map/geometry/index.ht...</a><p>It's hard to say which is better here, to be honest. A giant blob of gray is less helpful than showing some lanes, but the original version is much closer to the actual shape: <a href="https://www.google.com/maps/@47.6564275,-122.3223112,203m/data=!3m1!1e3" rel="nofollow">https://www.google.com/maps/@47.6564275,-122.3223112,203m/da...</a><p>Though apparently even google can't handle this intersection. Where did the middle layer of road go, google? <a href="https://www.google.com/maps/@47.6556467,-122.3191587,69a,35y,278.08h,79.19t/data=!3m1!1e3" rel="nofollow">https://www.google.com/maps/@47.6556467,-122.3191587,69a,35y...</a>
Very cool. Unfortunately it looks like I managed to put it into an infinite loop in the tutorial. Or possibly I just didn’t wait long enough after saving my changes…