[OSM-talk] Funding of three infrastructure projects : Nominatim, osm2pgsql, Potlatch 2

Martin Koppenhoefer dieterdreist at gmail.com
Tue Aug 4 15:08:53 UTC 2020

sent from a phone

> On 4. Aug 2020, at 16:26, Matthew Woehlke <mwoehlke.floss at gmail.com> wrote
> Obviously, this would all almost surely be a temporary mode (maybe it persists as long as JOSM is open, but isn't uploaded), but since you usually draw once, that would be fine. (Bonus points if JOSM could automatically recreate constraints for ways that don't have any. It shouldn't be hard to guess equality, perpendicular and colinear constraints, at least.)

rather than guessing, I sometimes have wished there had been a way to actually store relationships (geometric) in the data, something like these buildings all align their front facades, or this door (or building position) is aligned to this street axis, etc., so when people moved the street, the building would move as well. Would become very complex if it would be used extensively (basically you might move the whole city by moving a node, or it could lead to unresolvable constraints, etc.), so I think it’s not gonna come. Just accept some fuzziness ;-)

People are overrating rectangular buildings anyway, they might look more correct than a freehand approximation, but they typically aren’t (too short, too long, too wide, wrong angle not parallel to the street, not parallel to their neighbors, etc.), sometimes resulting from misinterpretation of aerial imagery and conscious or unconscious generalization (representing with a single rectangle what in reality is a rectangle with an oriel or a cutting or some other added shape). And sometimes a lack of diligence (e.g. when a building is on the crossing of two roads which aren’t orthogonal, it is not unlikely that the building isn’t orthogonal either, and it might be easily visible in the imagery, but if you only have a hammer, you might be tempted to use it for the screws as well).

Cheers Martin 

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