Steve Bennett wrote: > On Mon, Jan 4, 2010 at 3:08 PM, Claus Hindsgaul > <claus.hindsg...@gmail.com <mailto:claus.hindsg...@gmail.com>> wrote: > > Just rewind a bit; in the start of this thread, I cited a guideline > developed on talk-dk to aid the choice between separate and tagged > cycle-tracks/lanes on a street with the aim of getting the best map > description in the end. In the following discussions, I have tried > to outline why this guideline did not end up saying: "always > micromap everything". > > Yes, many of these discussions seem to devolve quickly into battles > between the "map everything in minute detail" and "exercise a bit of > discretion" camps. Then the two camps look at each other, realise that > it doesn't matter what the other camp thinks, and goes back to doing > whatever they want. It's one problem with mapping in general - if I'm > the only one mapping my town, I can pretty much do whatever I want, > because no one else is ever going to bother to look, or comment, or > change it.
That probably sums it up nicely ;) The problem at the end of the day is that the different levels of 'complexity' have to co-exist, so there HAVE to be some RULES. Existing 'routes' that are already mapped with a single 'complexly tagged' way should have the potential to be mapped as areas at some point in time. The problem is striking the correct balance between additional tags and an additional way, but with an understanding that a group of ways may be viewed as a single way at a higher zoom level. Width tags only really work on a single track, since the 'center line' requires symmetric structures. Adding tags to provide an 'offset' from a structure ( footway on left, cycleway on right and the like ) then require a lot more 'mapping' work over simply adding a footpath way interwoven with the vehicle way. In the case of structures that I would LIKE to map in my local area, footway and cycleway tracks form a lot more complex structure that personally I do not plan to map as 'offsets' from the existing vehicleway. AND the fact that there is no consensus on TAGS for ADDING that data prevents it happening that way anyway. :( As I have said all along. The different levels of complexity must co-exist and so a high level view must be able to combine data from the lower level and ignore any unnecessary complexity for that view. Arguments about 'routing' and the like do need to consider if the fine detail is necessary to accurately provide directions. In my one simple local case such directions as 'cross road and continue on the other side' are needed for pedestrian routing, but not vehicle. On a busy London road, where railings and pedestrian/cycle crossings are provided that fine detail DOES result in different ways for foot/cycle traffic over the cars. The same 'debate' applies to lanes on the road system, with routing direction able to pick up such things as 'get into inside lane and take slip road'. Again heavily populated areas will have separate 'ways' for pedestrians, cycles and cars, and while a dual carriageway through a town can be mapped as a single way with central reservation with fence, cyclelane left and right, footpath left and right all indicated with tags, that is just a very low zoom view. Moving in closer, and even for simple car routing at the higher level, two carriageways make more sense, and then you have to 'offset' which side has the other ways ... and start taking account of where cycles and people can cross to the other side. The problem is NOT at which level do you switch between on or other 'tagging style', but rather how do you combine the information from a lower view which shows the fine detail which is REQUIRED at that level into the higher level views? Claus - It's not a simple matter of 'aiding the choice between' - the more fundamental problem is how do we get both to co exist? If someone is going to DICTATE that we will never map some details then I think we have a problem? But that is where we are stuck at the moment anyway? -- Lester Caine - G8HFL ----------------------------- Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk// Firebird - http://www.firebirdsql.org/index.php _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
