[Qgis-developer] OSM viewer / sample styles online

Sat May 14 09:59:06 EDT 2011

Hi,
I've put online a sample .qgs project file with OSM dataset and
advanced/multi-scale qml styling (for 1.7.0 only), mainly ways, for
Monte Lema (on Italian/Swiss border):
http://www.mediafire.com/?jiooxkbmyzgr0
(File: OSM_Lema.zip)

The svg are harder to package and I have not updated this online (I must
dig for them and do not know what instructions to give for linking them)
so nodes will not be displayed well and I do not know what will happen
with ways with svg markers.
Additionally, some complex polygons were not correctly
converted from postgis to sqlite, but I attached what I could.
DEM and contour lines are much bigger, so not attached.
Hence this is more for you to see the technical organisation than the
final rendering, which you can see here:
http://www.qgis.org/wiki/OpenStreetMap_data_rendered_with_QGIS
Hopefully a slightly modified OSM plugin will make this work in one
click!
I used osm2postgresql to produce the original dataset.

Regards,
Mayeul

PS: For now, those styles and derived works are (c) Mayeul Kauffmann
CC-by-SA (similar to OSM maps and data). If this goes to the trunk, I'll
re-release with a more permissive licence if needed. I have already
released all the icons I created for this in the public domain.
MK

Le samedi 14 mai 2011 à 12:02 +0200, Mayeul Kauffmann a écrit :
Hi,
> In fact the issues 1)a,b,c,d are OK in the latest plugin (sorry).
> Still there are two main problems left, the roundabout issue plus a
bug
> in base code (see http://trac.osgeo.org/qgis/ticket/3825)
> 
> 1h. (that I forgot to mention): OSM plugin imports data as lat-long,
but
> while using "map unit" for the symbology the minimum value authorized
by
> QGIS is 0.01 degree (about 800 meters at longitude 45) which is much
too
> wide for any regional or city map, even for motorways. Working with
map
> units is the best way to have continuous zoom, and this is what I most
> often do in my styles (hence with metric projection only).
> So to have nice symbology with the OSM plugin, we need to reproject
the
> data (UTM) or to fix above bug (would be better).
> 
> I guess changing the "map unit" maximum resolution should be
trivial...
> but this need to be done in QGIS 1.7.0 as rules-based renderer in main
> 1.8.0 does not have support for symbol levels.
> Is there any interest from authorized committers to support/implement
> this kind of code change in 1.7.0?
> 
> (Working on the 1g), 2) and 3) steps can be done manually by the final
> user, but automatizing this would be nice).
> 
> Thanks for your feedback!
> Mayeul
> 
> Le jeudi 12 mai 2011 à 23:44 +0200, Mayeul Kauffmann a écrit :
> > Hi,
> > I would like to ask those interested in OSM viewing with QGIS, to
> > contribute to an improved QGIS  viewer of OpenStreetMap data, in
form of
> > a python plugin and, if needed, some modification in the trunk.
> > 
> > Recently I received several private emails asking me to share my
> > experience and/or files related to viewing OpenStreetMap data in
QGIS.
> > "One image is worth a thousand words"... I have just put 5 improved
> > renderings of OSM data here:
> > http://www.qgis.org/wiki/OpenStreetMap_data_rendered_with_QGIS
> > It uses the rule-based renderer (which just received support of
symbol
> > levels in 1.7.0) and osm2postgresql. More details on the method used
> > here:  http://www.qgis.org/wiki/Using_OpenStreetMap_data
> > 
> > The roadmap could be as follows:
> > 
> > 1. Slightly modify the existing plugin as follows:
> > 
> > 1a. while opening an .osm file, store the data in a format (let's
assume
> > spatialite, but could be other type) that allows long strings
(shp/dbf
> > have a 254 characters limitation)
> > 
> > 1b. in the spatialite files, store in a single field named "tags"
all
> > the concatenated tags for each feature.
> > Should look like this:
> > "access"="private", "amenity"="parking", "parking"="underground"
> > This example is how I manage this node:
> > http://www.openstreetmap.org/browse/node/989971901
> > 
> > (The comma can be replaced by any separator, even a space; comma is
for
> > readability for humans).
> > 
> > (Optionally here, we can drop the following tags: "source",
> > "modified_by", "edited_with" and the like. The shorter, the best
> > performance and the smaller the files).
> > 
> > 1c. remove all points that are left with no tags after dropping
these
> > tags (those are just vertices or noise)
> > 
> > 1d. store the "name" tag in a "name" field (for labelling).
> > 
> > 1e. do not store roundabouts as polygons but as ways (this is the
most
> > common problem generated by the plugin when assuming that closed
ways
> > are polygons; this is impossible to have a nice rendering of
polygonized
> > roundabouts).
> > 
> > 1f. put the required layers in a single group layer
> > 
> > 1g. automatically apply a set of .qml files
> > 
> > The alternative to the above (1) is to use my osm2postgresql bash
script
> > (this requires a linux box; the script installs the server if not
done
> > yet; one of its advantages is correct management of polygons with
holes
> > and good performance at the country level).
> > 
> > 2. Distribute the .qml files I created with the plugin or with QGIS
(no
> > idea of what is best)
> > 
> > 3. Distribute  with the plugin or with QGIS the icons I generated
(no
> > idea of what is best).
> > (Optionally: ask [again] SJJB management icon authors to backport
svg
> > bug fixes and share related bash scripts)
> > 
> > Ideally: for 2 and 3, think of how people would contribute their
> > alternative OSM rendering using the QGIS OSM plugin.
> > 
> > 
> > I would really appreciate collaboration of at least one python
developer
> > for (1-2-3), and [if needed] of a QGIS core developer for (2) and
(3).
> > I have very little experience with QGIS python plugins. Since I do
this
> > on my spare time only (to prepare my hiking maps), without help this
> > will take ages and I have little personal interest in doing so (it
> > already works on my machine, so...). Also, I could put my .qml on
> > rapidshare, my .svg on openclipart and my bash script to create the
svg
> > on the qgis wiki... but I won't, since those solutions add a lot of
> > hassle in data and code management and do not deliver what I would
like
> > to contribute to:
> > "Fast, easy and beautiful on the fly rule-based rendering of OSM
maps"
> > Cf. http://trac.osgeo.org/qgis/ticket/3222
> > 
> > I would like to spend time improving the symbology rather than
coding
> > the above 1, 2 and 3, hence my question: anybody interested in
> > contributing to an improved QGIS OSM viewer plugin?
> > 
> > Thanks for reading, and thanks in advance for any answer!
> > Regards,
> > Mayeul
> > 
> > PS: If we can do the above and test it with the QGIS web client, we
> > could do a killer demo at the OSM state of the map conference in
Vienna
> > this summer, something like: "Create your Customized Slippy Map in
10
> > Minutes with QGIS".
> > MK
> > 
> > _______________________________________________
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> > Qgis-developer at lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/qgis-developer
> 
> 