Hi Jeroen,
On So, 2015-04-12 at 15:46 +0000, JJJ Wegdam wrote:
The first slice is on milestones. The milestone import already has
it's own wiki section within the ProRail import wiki. You can read all import details
there. The tagging, however, is very important to ORM. This because the milestone
placement in the ProRail database is quite in another way than is described in the ORM
tagging scheme. Quote: ''They should be entered as nodes on the tracks themselves.
If the railway line has more than one track, it should be entered on each track.''
I personally object to such an approach, because it neither encompasses the theoretical
nor practical situation. The theoretical situation is placement of milestones directly on
the reference ribbon, along the centre of a railway line. The practical situation,
however, is placement of signs perpendicular from the reference ribbon (note that this can
create other signs intervals than described on the signs).
Railway companies mostly use the reference ribbons in their maps and systems, because
those values are more precise. I would propose to make mapping of the theoretical and
practical locations of milestones possible, by allowing these systems on the wiki.
Importing the Dutch milestones automatically would be impossible without such permission.
mapping the milestones as nodes that are part of the tracks has some
advantages:
* in bigger stations with some parallel railroad lines it would be
difficult for mappers to see which milestone belongs to which track; for
software it is also nearly impossible to identify which milestone
belongs to which track, especially if there is no additional information
such as track numbers
* for routing purposes (e.g. generating a speed profile with the
positions of speed limit changes), I would prefer to have such data as a
part of the tracks; if the milestones would be mapped as separate nodes,
preprocessing is necessary to "project" the milestones on the tracks
So I would prefer to import the milestones as part of the tracks. I
agree, that this is not possible as an automatically import. But maybe
we could map them manually and start a mapping campaign. This topic is
easy even for non-railway mappers, so there are many mappers that could
help us. People trace thousands of buildings in Haiti within some days,
so why not adding thousands of milestones in the Netherlands? ;)
Any other ideas?
Regards
Alex