Recent Posts

Pages: [1] 2 3 ... 10
1
Other Discussion / Re: county collecting (from AARoads)
« Last post by yakra on Today at 11:58:14 am »

Quote from: yakra
I can upload the WPTs to GitHub or email them if you'd like. They're 908k zipped up.

Scattered thoughts:
• We'd need to pay more attention to edges than vertices, which gets... more involved. I won't get further into that, because brevity. :)
Not aware of any such instances in MS, but there's the case of holes in polygons, E.G. a county entirely surrounding another county or group of counties. WPT, only intended to represent polylines, won't support this, but SHP does. A more detailed...
Quote from: a more recent revision of the shapefile spec
A polygon consists of one or more rings.  A ring is a connected sequence of four or more
points that form a closed, non-self-intersecting loop.  A polygon may contain multiple
outer rings.  The order of vertices or orientation for a ring indicates which side of the ring
is the interior of the polygon.  The neighborhood to the right of an observer walking along
the ring in vertex order is the neighborhood inside the polygon.  Vertices of rings defining
holes in polygons are in a counterclockwise direction.  Vertices for a single, ringed
polygon are, therefore, always in clockwise order.  The rings of a polygon are referred to
as its parts.
A possible workaround: check whether all a county's polylines are themselves within another given polygon.
If doing this in, say, Virginia, allowing holes in polygons would be more necessary: Independent cities.

Do I see another HDX file type on the horizon, for multi-part polygons? 8-)
2
Other Discussion / Re: county collecting (from AARoads)
« Last post by yakra on Today at 11:57:21 am »

Quote from: Jim
I am teaching Algorithms in the spring, so this could happen...
3
Other Discussion / Re: county collecting (from AARoads)
« Last post by yakra on Today at 11:56:45 am »

Quote from: yakra
I now have WPT files for each of 82 counties. 8-)

Quote from: SHP file format spec
A polygon consists of a number of rings.  A ring is a closed,
non-self-intersecting loop.  The order of vertices or orientation for a ring
indicates which side of the ring is within the polygon.  The neighborhood to
the right of an observer walking along the ring in vertex order is the
neighborhood inside the polygon.  Vertices for a single, ringed polygon are,
therefore, always in clockwise order.

As far as querying a county goes, how about this...?
Search for the nearest vertex or edge to the lat,lng point. (The QuadTree can help with this, yes?)
Each edge can store 1 or two associated polygons, just as a TMG file stores an edge's associated routes. (In an HDX style view, county lines would be green, and the state line blue.)
The vertex order would determine whether the lat,lng point is in the polygon on one side, the polygon on the other, or not within any polygons / outside Mississippi.
4
Other Discussion / Re: county collecting (from AARoads)
« Last post by yakra on Today at 11:55:49 am »

Quote from: Jim
Sounds like a great motivation to combine Travel Mapping data with county information (is there an free/easy/automated way to query the county for a given lat,lng point?).  If I could do that, this could be a fun task for me or my Algorithms students...
5
Other Discussion / county collecting (from AARoads)
« Last post by yakra on Today at 11:54:36 am »
https://www.aaroads.com/forum/index.php?topic=19635


Quote from: hbelkins
Here's your assignment, should you choose to accept it.

Plot the shortest, best and most direct route to pick up all the counties in white that lie north of I-20, beginning in the north and ending in Jackson.



(Crossposted to the Road Trips board...)
6
In-progress Highway Systems & Work / Re: usaak (Alaska State Highways)
« Last post by oscar on Yesterday at 08:13:12 pm »
I looked at the files you cranked out, in a web browser and a text editor. I have no clue on how to use them, and in particular I didn't see anything resembling coordinates. What am I missing?

I'm not sure I'll need to use those coordinates, even though they're for the two routes with the worst mapping where I didn't supplement that with handheld GPS reads (AK 6, and AK 10 east of Chitina), since I think I was able to draft adequate route files with what was available from Mapnik.

When I return to usaak, to incorporate the peer review already completed and work in other updates, I might have some specific coordinate/route segment requests. That will probably happen early in the new year, once I'm finished getting usaca ready for peer review. I'm down to about three dozen usaca routes in need of updates, though some of the remaining urban routes may have issues about what to do with relinquishments.
7
And there still is a broken concurrence between I-580 and US 50/395. The I-580 shaping point south of exit 38 doesn't match that for US 50 and US 395.

To un-break the concurrence, all waypoints along the I-580/US50/US395 concurrence, including shaping points, need to have identical coordinates. And all points at the I-580/US50/US395/US50Bus/US395Bus junction also need to have identical coordinates (the point in the US395 file doesn't have the same coordinates as the other four files).
8
Updates to Highway Data / NC: I-85 / US52 concurrency broken
« Last post by yakra on Yesterday at 01:51:05 pm »
I-85 @ 79: http://www.openstreetmap.org/?lat=35.678459&lon=-80.413828
US52 @ I-85(79): http://www.openstreetmap.org/?lat=35.677762&lon=-80.415115

Recommend replacing the coords in the US52 file with those from the I-85 file.
9
In-progress Highway Systems & Work / Re: Montana Secondary State Highways
« Last post by Duke87 on Yesterday at 01:46:24 pm »
SR 441: needs a shaping point between FaiRd_W and FaiRd_E. Route follows Fairmont Rd as OSM shows.
SR 444: point "HorRd" needs recentering
SR 446: OK
SR 447: point "RosEstDr" needs to be moved and renamed (there is no intersection here, or any intersection with a road of this name)
SR 448: "Rd80_S" → "80S" (matching format of other similarly named points)
SR 449: truncate to 160N (this matches the 16.59 miles from US2 shown in road log)
SR 451: coord mismatch with WY 345 at state line'
SR 453: OK
SR 457: OK
SR 462: OK
SR 463: OK
SR 464: OK
SR 466: OK
SR 467: "MT200_W" → "MT200", "MT200_E" → "MT200S"
SR 470: OK
10
Updates to Highway Data / IL: IL390 (Elgin-O'Hare extension)
« Last post by SSOWorld on Yesterday at 11:25:10 am »
Route now open from I-290 EB to IL 83.

Interchanges at Prospect Ave (Exit 13) and Wood Dale Road (14).  IL 83 is current terminus marked as Exit 15.

https://www.illinoistollway.com/documents/20184/145046/ILTollwayMap_2017-SideA-web.pdf/b1259da8-476c-4766-b5f7-912c6f0c339a
Pages: [1] 2 3 ... 10