Ok, I’ll try again shortly with the device in an optimized position. Had to try the simple variant first. At least with such a small device it is much easer than with a brick like a telephone.

Oh, and another remark. I am using the associatedStreet relation instead of individual addr:street attributes for a number of reasons. First of all, from a database point of view, I think it is better to represent the relation between houses and streets directly instead of hold the street name redundantly in every house object. Also, here in Catalunya the streets mostly have both names in Catalan and in Spanish, so I would have to put at least two localized names in every house for the entire relation to hold regardless of language. The default name put on the streets could be either es or ca, so the default name put into addr:street does not necessarily have to match the default name of the street, which could lead to some confusion. With a relation, the common property is the object id of the street, not the spelling of the name, and is automatically has all translations. There are a few minor problems because on the octogonal squares at the local street crossings, a physical building might have house numbers for two different streets for different entrances or even the same entrance hall. In that case, I pragmatically split the building in two seperating the parts according to the adjacent streets. I thought about using entrance nodes, but I do not have enough time to do that accurately enough to be used for accessibility applications right now.

My general mode of operation is that I first prepare the building outlines using aerial images from bing, then print out the blocks in a map (funnily enough, JOSM does not seem to have a print command, so I make a screenshot, invert the colors with GIMP to get rid of the black background, scale to A4, then print…), and take a walk to the location to check the house fronts to see

• if there still is a building at all :-)
• if the building boundaries are more or less correct
• important installations to add immediately (in my quarter I probably would need a special tag “on this corner there is NO banking office” ;-)
• scribble down the housenumbers for each building.

Then I go back and add the most important informations to the map.

I am using the predefined template in JOSM, so I don’t have to spell it myself. the street relation is for binding together different segments of the street into a logical object for the whole street.

Sanderd17, thanks for the hint.

Oh, I did not take into account that in August EVERYBODY is away for vacations. It looks like they were in such a hurry to get away that they forgot to put a note at their online shop that orders are pretty useless until september…

Ok, thanks for the info. Probably won’t be that active for long myself, since funding and time seem to be mutually exclusive resources ;-)

Ah, thanks for the info. I think I had some wrong ideas about how aGPS actually works. I thought it worked based on radio cell information and provided continuous information. I did a larger tour following one of the central streets from more or less in the middle of Barcelona to the beach and back again yesterday (osm.org/user/asgalon/traces/1291334) and the accuracy gets much better when away from higher buildings. What surprised me was that the trace while riding the bus back seems to have been as accurate as while walking.

I’ll make some comparisons with both devices active in a couple of days. It already looks like in small parks and open areas like at the beach the accuracy is much better than between buildings. I actually came to participate because I am developing a mobile application with mapsforge which will be mainly used in the town area with Android smartphones, so I was wondering how well this would work locating the position with GPS receivers used in normal mobile phones. I already saw that you can get a general idea where you are and fix the exact position using the map if there are sufficient details, but for recording mapping information it seemed a bit coarse. So probably this investment was absolutely superfluous, but that too would already be a result worth noting… So, more of that next weekend when I can compare tracks.

Also, adjacent buildings may have same roof height, but different internal configurations, so they probably should be represented in 3D with objects of the same height.

Well, I am looking at the configuration on the other side of the street, which is one of the blocks I am editing. There you can see a line of windows of the entrepiso, which is clearly above ground level, and contains normal height office space, but part of the entrance level architecture and looking different from the upper floors. If you don’t know the label on the elevator button, you can’t really tell whether this is 1st upper floor or entrepiso. So for this type of entrepiso I think counting in the level would be appropriate, because it would match slightly better what a map user not familiar with the local architecture details sees while standing in front of the building.

Great, thanks, that clarifies it. “intermediate” was a wrong translation. They are called entrepiso in spanish, that would be mezzanine or entresol.