2019-02-11, pr, 11:29 Ture Pålsson rašė: > As someone who tries to render smallish-scale (typcally 1:25000 or > 1:50000) maps from OSM data, I am always slightly annoyed when someone > states that something does not need to be mapped bacuse it can be > inferred algorithmically from other data, without describing or at least > giving a reference to such an algorithm. > > Tree rows -- real tree rows, i.e. a row of trees planted on purpose to > function as a landscaping feature, not just some random trees which > happen to be in a line -- are important landmarks and often show on maps > as rows of green dots. However, the individual trees are typically too > close to be shown at their real positions, so some generalization is > required. Tagging the tree row provides such a generalization. I have no > doubt that it is theoretically possible to synthesize tree-row objects > from mapped trees, but I would guess that doing so with an acceptable > number of false positives and negatives is close to a masters-thesis > project.
Exactly! Two things to add: 1. At least in Lithuania cartographic (topographic) "tree row" is defined as "a row of trees groing alongside a road or railway". That is random trees somewhere in a field do not become a "tree row" even if they are in a row. 2. If (1) is true in other countries, maybe "tree_row" should be an attribute of a road/railroad? Say highway=residential+tree_row=left|right|both. This way it would be much more convenient to create cartographically correct maps in 25k 50k scales without resorting to complex generalisation operations like displacement? -- Tomas _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
