OpenStreetMap

Paul Johnson has commented on the following diary entries

Post When Comment
Search Engine Optimization Destructive Edits 2 months ago

Not on Twitter, but I did the equivalent on G+. https://plus.google.com/+PaulJohnsonTulsa/posts/1YtDPqM3CEv

Releasing Turn Restriction Detections 3 months ago

I'm looking forward to this going into the Improve OSM plugin.

Motorway Junction Node Placement 3 months ago

Well, it's not always not noticeable. Washington and Texas have very, very long exit lanes, sometimes the entire distance between ramps that might be miles apart (Washington for example, expects you to signal your turn the entire time you're in the turn lane and has reminder signs to this effect...especially annoying when the turn lane is ~7500 meters long!). Washington and Oregon also have noticeably shallower, longer gores compared to most other states ramps as well, option 2 gives a prompt so early on Garmins and Osmand that you're not even to the theoretical gore before the announcement to turn at the top of the ramp starts and you might be at or past the decision point for the next ramp by the time the first prompt after entering the freeway plays. Plus option 2 gets plain hard to deal with if the freeway is also on a curve.

This is less prone to be an issue with my preferred method, but does occasionally come up on comically huge gores built up from decades of interchange revisions, a relatively rare trade.

Motorway Junction Node Placement 3 months ago

How about a fourth contender.

Player four, FIGHT!

Imagery is Bing, location is https://www.openstreetmap.org/way/180337791

I think the objects are clear enough in the shot pretty self explanatory as outlined. The placement=transition highlighted is joining the highway=motorway_junction node placed on the inner westbound carriageway centerline longitudinally even to the theoretical gore point, and goes as smoothly as possible to the centerline of the exit ramp, longitudinally even with the physical gore.

This also (fairly) neatly handles starts and ends of medians as well, the "transition" segments start at the physical gore (end of the median) and continue to the theoretical gore (pavement markings). Where a both_directions lane is present, then it goes from the end of the double solid lines on both sides to the bullnose.

Using OSM in Mobile 5 months ago

I'm also a fan of Osmand.

Trunk in a funk 7 months ago

US 6 between spanish fork and I 70 being trunk is leftover NE2 vandalism, from when he bulk-retagged all US routes that weren't motorways as trunk regardless; and the history on a random sample of segments confirms this. I'd generally consider that a primary; the tiger import got it right on this.

UT 154... I'm not seeing a reason any part of that should be motorway. Seems pretty clearly a trunk through and through. It might later become a motorway if the at-grade intersections intermediate and at the south end is eliminated.

US 89, agreed, that's definitely a trunk between Farmington and I 84. North of I 84, looks like it turns primary and is yet another example of NE2 smash-tagging everything with US in the ref as trunk.

Mapping Center Turn Lanes in the United States 7 months ago

Looking at that example screenshot, kind of leads more support to my theory that it's time we start tagging for where the parking strip and bicycle lanes are on the street in order to provide correct lane guidance.

Mapping Center Turn Lanes in the United States 7 months ago

In general I change the centre_turn_lane=* or center_turn_lane=* tagging to the more widely used turn:lanes tag.

Composite keys in OpenStreetMap: ref:highway, highway:ref or highway_ref? 7 months ago

I'd argue that using ref=* on highways to describe road routes was a big mistake in the first place and a legacy of not having relations. This further complicates things in that Oregon has separate highway numbers and route numbers that don't usually match up; the highway number belongs to the road, not the route; and the route number might cross several different highways.

The case for highway=trunk on Texas frontage roads 7 months ago

Yeah, that gets fun in Texas. I'd probably consider Dallas Parkway a Primary because of the frequency of driveways and intersections, despite being the outer roadways to the Dallas North Turnpike. But, the newer four-way motorways (which are the standard in Texas anymore) do tend to have more of a SRT/TX 121 layout.

Blanket rule doesn't really work, still should be on a case-by-case thing on the Texas 4-way motorways.

The case for highway=trunk on Texas frontage roads 7 months ago

The rural Texas frontages, I definitely agree with Richard on. However, the urban version, such as you find on TX 121 where the Sam Rayburn Turnpike runs down the median? That's pretty much a textbook trunk already.

The case for highway=trunk on Texas frontage roads 7 months ago

Depends on the frontage system deployed. Rural frontages, I'd tend to call tertiary save for the sections feeding from and to the motorways to the relevant cross street.

Urban contexts where the system is one-way? At that point you have a surface expressway, which is normally a trunk, that has a freeway (motorway) down the median of it. I agree in the situations where the outer roadways are one-way and go through, the outer roadways should be trunk.

How would you map this? 12 months ago

If U turns are not restricted, it doesn't make sense to add the restriction to either possible option, routing engines will universally pick the shorter option.

Also, yeah, I really would rather go with a relation for traffic signals on a situation like this, since node mapping fails highway=traffic_signals, highway=give_way and highway=stop situations in all but the simplest of cases, and would like to get more support for doing so. Until then...node tagging works as a placeholder and something a potential future MapRoulette challenge can latch onto.

How would you map this? 12 months ago

@Escada Which movement are you referring to?

Also, thanks for making me doublecheck, I forgot to tag the traffic light junctions. I see someone added a left-turn restriction, but I'm not sure if that's actually the case or not (depends on if a U-turn is legal from 3100 south or not, and if not, then a couple more restrictions need to be added).

How would you map this? 12 months ago

@mvexel: This is where placement=* comes into play. Osmand generally assumes you will end up in the corresponding lanes once you get around the corner, which from my experience is a reasonably safe assumption (and follows either best practice or the law everywhere to the best of my knowledge).

This does mean that you sometimes have to work out the centerline of through lanes for miles at a time, something in my quick and dirty example I only did to a logical stopping point. And sometimes, switching the centerline location because, say, a new lane joins on the right, then miles later a lane gets dropped on the left. I usually make such a transition at the drop if possible, tagging which lane ends, with the end of the lane line starting a new segment with one fewer lanes, placement=transition. I also use a placement=transition for situations where one or more sides of a link face a flush median like a theoretical gore, and have the junction node even with the point that theoretical gore's nose, ending at the ramp's centerline start adjacent to the bullnose.

How would you map this? 12 months ago

OK, I've taken a crack at it. You'll probably need to use JOSM with a lane-aware rendering style. Osmand should give proper lane-level guidance on this intersection now.

How would you map this? 12 months ago

What's the location? I can take a crack at this. I've had experience mapping a pretty big variety of intersections now as I try to lane-map every state highway in Oklahoma.

Are you joking ?? about 1 year ago

I, too, am missing what is wrong with this picture, and I've been to the area in question.

7.5cm aerial imagery for Washington, DC over 1 year ago

Be sure to include placement as well. Such as in the above example, placement=middle_of:3

How to deal with broken relation over 1 year ago

If you really want to go insane, try mapping routes that have a lot of ways that appear more than one time in the same relation...and accidentally sort it