Hallo! Wie geht es Ihnen?
(Sorry but I’m not brave enough to continue with my rusty Deutsch. :P)
Following a recommendation by a German user (username “nesol”) and because the German-speaking community is the most active in OpenStreetMap, I would like to share with you a flowchart that the Brazilian community has recently come up with to simplify assigning the “highway” tag. It kind of synthesizes what is written in many articles in the wiki, and also adapts these definitions to the Brazilian context. We’ve tried to use as few ambiguous characteristics as possible in order to minimize edit wars. Such a simplification is good for beginners and (we hope) it may be an aid in ambiguous cases because it clearly states priorities established by consensus. I think it is reasonable to say that we aimed at never producing incorrect results, just maybe slightly inaccurate in a few cases (hopefully much less than 5% of the time).
Nesol helped me improve the German translations. He also pointed out a major difference with the classification style in Germany, Austria and Switzerland (DACH): the usage of “tertiary” roads outside urban areas, which are paved in DACH but (now) unpaved in Brazil. The flowchart also contains an official national classification in the boxes with a “[br]” prefix. Note that the nodes in green (outside urban areas) and yellow (inside them) are very specific to Brazil, while the others are somewhat more “universal”; perhaps a notable exception is the application of “living street” since this kind of way does not exist in Brazil officially.
You can see the German version here: http://i.imgur.com/CuZcyRC.png
There is also an English version here: http://i.imgur.com/YH8azIA.png
Source yEd graph files: https://www.dropbox.com/sh/8ifgduyovz9880u/sOE2QvDLci
We’ve gone through hundreds of e-mails making improvements (adding or loosening requirements, and also changing the flow). It hasn’t suffered any major change in the last week, so it can be considered stable. However, opinions and suggestions are more than welcome. You can also freely modify and use the graph files.
We are largely based on the text in the English wiki, which is the most accessible to the Brazilian community, but we also considered approximations to the classification style used by our Latin American neighbours.
I know there is a user currently applying this method to major roads in the state of Rio Grande do Norte (RN), but I don’t know his progress yet. I have applied it to all urban ways in the city of Porto Alegre, where the results of “rising by priority” can be clearly observed.