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For some particular application purposes, I need some middle-scale of OSM data, for example, 1:10k or 1:50K. Thanks in advance!
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Would it work to use the overpass API with a query that only looks for some object types but not others? E.g., you could filter out highway=service but keep highway=motorway (highway=* values reference). In addition to whitelisted tags, you probably want to also retrieve any closed way whose area is larger than some lower bound (e.g., for landuse=* / landcover=* tags); I'm not sure how to do that. |
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Of course, there are many users creating “middle-scale” OSM vector datasets. Actually, an efficient and modern (OSM) vector based GIS system and/or digital cartography should (must) have these pre-generated scale levels. These levels are preconditions for efficient data transmission, rendering, arbitrary scaling, rotation, styling, flexible overlays… just to mention some. The number of scale-levels and their position in the spectrum of 1:500 – 1:300M (million) depends on the object type and on some strategic criteria. As an example see the image1, https://goo.gl/CPnWxs, an extract from a map scaled by 0.54 from the scale level 5 containing planet land, lakes and rivers data layers ( the number of nodes is reduced 68.5, 162.0 and 459.9 times consecutively). |
What do you actually want? Map tiles? Vector tiles? A map you can blow your nose on?
I meant OSM data - points, lines and polygons, rather than tiles or images.
Data available here: https://www.geofabrik.de/data/download.html
These are the largest scale of OSM data. Any middle-scale of OSM data? Thanks!
There is no such thing as a "middle-scale" of OSM data, or for that matter any scale... There is just node,way and relation data, which has varying accuracy. You yourself! need to make the proper and smart selections, and potentially generalize and style the data, to get the kind of "middle-scale" topographic(?) map look you want.
Many thanks for your comments!
I see your point. Then I wonder how OSM created those middle-scales and small-scales, from which different zoom levels (http://wiki.openstreetmap.org/wiki/Zoom_levels) were generated. Is there any standard for generating middle-scale and small-scales?
"Is there any standard for generating middle-scale and small-scales?"
Well, yes and no.
Of course there is 100+ years of topographic maps from many national mapping agencies around the globe as your guide, and the main Standard style (aka "openstreetmap-carto") has an open GitHub repository with SQL and zoom levels: https://github.com/gravitystorm/openstreetmap-carto.
But none of this is really a hard standard, so other than that, you are on your own.
I spend the past 4 years developing my own advanced topographic map style for ArcGIS... there is lots of cartographic research and trial and error going into a truly sophisticated display at different scales, and especially the topographic scales of 1:10k - 1:50k, where space is limited and a desire to show a lot.
Thanks all for your answers! It is sure that there are no middle-scale or small-scale OSM data available, not to say any arbitrary scale of OSM data. However, cartographic community and the European INSPIRE project have been working very hard to create middle-scale and small-scale maps from a single largest-scale database (https://inspire.ec.europa.eu/). Unfortunately little progress is made, and subsequently, national mapping agencies around the world have to maintain multi-scale databases simultaneously. The multi-scale databases create a lot of problems of maintaining, updating, and harmonizing, not only within a single country, but also across borders. Generations of cartographers have been working very hard towards automatic map generalization, and it would save a lot of man-powers and computing storage.
It is possible to create a convincing topographic multi-scale map from OpenStreetMap data across a wide range of scales without massive (batch) generalization. My ArcGIS Renderer does this, and I think OpenTopoMap also does a pretty good job (https://opentopomap.org). It does require a re-thinking of what a map should look like, especially in this time of ubiquitous web maps designed to be readable even on horrible low resolution screens. You cannot create a convincing topographic map against such lowest common denominator. Drop support for 90dpi devices, and start designing for minimum 150dpi / 300dpi devices and true offset printed paper maps only. This will allow you to use far smaller font sizes and line widths, creating a true topographic look and feel if done well.
Where can I see or test your ArcGIS renders? Thanks!
It is not yet publicly available, but I have made some test renderings and images available in the below links. Do note that the actual styling is pretty outdated for the first - earliest - link of about three years ago, as I have made considerable changes and improvements since then. Also, contrary to what I wrote back then, I have expanded the style to a full multi-scale map, from 1:50M down to 1:1k:
OLD outdated styling, but large PDFs: Various 1:10k - 1:50k:
https://forum.openstreetmap.org/viewtopic.php?id=26451
and
https://forum.openstreetmap.org/viewtopic.php?pid=448946#p448946
NEWER styling, but only small image snippets: 1:2500 large scale:
https://forum.openstreetmap.org/viewtopic.php?pid=578345#p578345
1:10k:
https://help.openstreetmap.org/questions/49697/is-a-vector-map-layer-planned-for-openstreetmaporg/55932
+/- 1:25k:
https://github.com/gravitystorm/openstreetmap-carto/issues/1500#issuecomment-96587116
I have the similar question, Where can I download some small-scale of OSM data?
By the small-scale of OSM data, I meant the data used to create OSM map tiles shown in the website: OSM.org
Any comments are highly anticipated.
Thanks in advance.
Bin