OpenStreetMap
I had a dream about OpenStreetMap last night.
I had a dream that a fellow mapper in the area had micromapped some random town down to the nth degree. It was brilliant, and it made me realise we need some lovin' on the mapnik layer.
For the longest time it's been my opinion that there needs to be some kind of grid system to line up points and ways, because as it stands it's very difficult to get an accurate satellite trace turn out as an aesthetically pleasing map. The orthogonalise feature in JOSM is nice, but more often than not it will skew things differently, so you've got nice even buildings that are all out of line with each other.
With a lower resolution grid in the editor, you could sacrifice accuracy by a tiny margin but make everything look aligned and oh so much nicer. Imagine a street-front that's not all wonky! (My own case in point., it's just too difficult to line everything up.)
It's also my opinion that we need some nicer icons. This is something I can at least help with; if there's sufficient community support I can come up with a new scheme. I quite admire the CloudMade rendering, with the little tile-like images although perhaps if we were to come up with an unified OSM colour scheme, we could do even better.
I'm not sure if any of this is viable. Is there enough interest for a new icon scheme? Would a snap-to-grid feature in JOSM be all that useful? I don't know, discuss. :)
Discussion
Awennit n Biogenesis_ di 13 July 2009 ɣef 06:29
The obscene accuracy presented in the co-ordinate system by JOSM really goes a bit too far, yes. Glancing at a BBOX measurement and the latitude was reported to no less that 13 decimal places. A back of an envelope calculation shows this to be precision to, oh, about 1/10th of the width of a hydrogen atom.
From memory a 6dp truncation of lat/long leads to a ~10cm grid near the equator.
The trouble is that from a programming perspective JOSM just uses basic floating point functions, in order to do such a truncation requires jumping through lots of rings programming wise.
But yeah, a, say, 1m "snap to grid" would be useful, however it's very rare that a building will line up exactly with the lat/long grid, so it may be a waste of time. Perhaps a tool which orthoganises an area but allows you to force arbitrary segments to be parallel (ie, side of a building to the street next to it) would be a big step up.
Personally I'd love to see an "area paint" function which allows you to click in the middle of, say, 4 intersecting ways and say "everything in there is landuse=blah" and it automatically draws an area in parallel to each way with a pre-defined offset of ~5m or so. Kind of like the Photo editing "bucket of paint" tool.
Anyway, just some thoughts.
Awennit n CatastropheAsh di 13 July 2009 ɣef 07:58
I guess you're right, I've been doing some reading and I'm finding myself in a level of mathematics that's way over my head. I'd love to see some kind of advanced/magic hinting algorithm, but it sounds a bit outside the scope of JOSM at this point.
I might have another crack at little Banyo town and see if I can make it look any better now I've got more of a feel. It was an earlier OSM project of mine, and could probably do with a tidy anyway. :)
Awennit n HannesHH di 13 July 2009 ɣef 09:12
There is a trick on how to get nice orthogonal buildings. Start with only one edge of the building (1 way with 2 nodes). Then select that way and use the "create Areas" tool (X). With more complex buildings you will have to remove some obsolete nodes in the end.
The area paint idea sounds awesome.
Awennit n HannesHH di 13 July 2009 ɣef 09:15
Maybe an extension to the "align nodes in line" tool where you can fix certain nodes and have the others be put on their line would be possible.
Awennit n Biogenesis_ di 13 July 2009 ɣef 11:23
Upon the advice of user davidearl I made a JOSM ticket for the area paint tool here.