On Fri, Oct 13, 2017 at 8:17 PM, Greg Troxel <g...@lexort.com> wrote: > Agreed mostly. But I don't see primary/secondary as having anything to > do with physical; we more or less defined that as US vs state long ago.
If you read the description on the Wiki, we defined no such thing, we merely said it was an indication: 'primary' is "A major highway linking large towns, in developed countries normally with 2 lanes. In areas with worse infrastructure road quality may be far worse." and then we say "U.S. Highways are *mostly* primary." (emphasis added). And that's true largely because they were imported that way from TIGER, for weal or woe. Examples: US 6 between Port Jervis and Middletown, NY is really no longer even primary. In that stretch it isn't the major highway linking those towns. Interstate 84 now serves that role. US 6 is maintained there chiefly as a detour route in case I-84 has to be closed for some reason. I'm also not sure that I'd accord it 'primary' farther east, between Woodbury and Bear Mountain, because it's 'hgv=no' and has a reduced speed limit in the park. By contrast, NY 17 is a freeway. (It's signed, "Future I-86" in spots. I'm not sure what's blocking the designation- it is I-86 farther west.) NY 5, on the north side of the Mohawk, is correctly labeled a 'trunk' for most of its length. (It slows down and has stoplights in the larger towns, but is dual-carriageway with only infrequent at-grade crossings.) NY 30 is surely at least 'primary'. It's a bad two-lane road in a lot of places, but it goes through remote and mountainous parts of the state and is The Big Road in virtually every community it visits. Ulster County Road 47 is a primary (or secondary at the very least), two-lane (uhm, usually) gravel (or sometimes asphalt) road. It was formerly signed NY 42 - and there are sections of NY 42 beyond both ends of it. But the state, some years back, decided that a road through the mountain range there could not be maintained to state highway standards and turned it over to the county. The non-hard-surface sections were downgraded because they're easier and cheaper to maintain, and with the well-compacted surface, the road runs surprisingly fast in summer. (In winter, it's pretty challenging - snow removal leaves something to be desired, and there's a LOT of snow up in the pass by Winnisook Lake.) But for the villages of Big Indian, Oliverea, Frost Valley, Claryville, it's The Highway. Reading the descriptions on the Wiki, they all are talking about importance, not size. "Secondary" is defined as "A highway which is not part of a major route, but nevertheless forming a link in the national route network." "Trunk" is "Use highway=trunk for high performance or high importance roads that don't meet the requirement for motorway." This is the only one that's hedged: "In different countries, either performance or importance is used as the defining criterion for trunk." By contrast, if we want to say, "how big a road is this" for rendering, we have a collection of attributes that can inform it: "lanes", "maxspeed", "maxweight", "hgv", single vs dual carriageway, presence or absence of grade crossings, ... So in an ideal world, it's less of a stretch to say that "highway=*" is the "importance" metric (which would determine the map scale at which the road is relevant), and the bucket of physical attributes that I mentioned is enough to determine "size" for the symbology. I don't know if "maxspeed" by itself is enough for routing, or if other information is needed there; I generally consider routing to be Someone Else's Problem. Nevertheless, we live in a real world in which a TIGER import did indeed tag roads by administrative level - surely a surrogate for neither size, nor speed, nor importance, and in which people argue whether a dual-carriageway county road could possibly be anything higher than 'tertiary', and tag a dual carriageway as "motorway" with downgrades to "trunk" for barely the width of each grade crossing. I don't know what to do to get from the world we live in to a world where the useful attributes for selection, rendering, and routing are separable. _______________________________________________ Talk-us mailing list Talk-us@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-us
