[openstreetmap-website] Replace scale with zoom level in Export tab (#368)

Ilya Zverev notifications at github.com
Sun Jul 21 05:52:04 UTC 2013


Zoom coefficient relative to the displayed bounding box size is an idea similar to one I proposed: instead of adding 1 to the zoom level, you specify coefficient of 2. The downside is, zoom level affects map detalization: features at zoom 13 significantly differ from zoom 12, for example. Such coefficient, as well as scale, obscures this, and I think detalization of the map is the major reason for a user to alter scale/zoom level/zoom coeff (the second one being getting as bigger image as possible).

Size of a pixel is hard-coded somewhere in mapnik style: I remember there are pre-calculated values, from which it is possible to derive a required equation. As of now, I think there are three different algorithms (with different coefficients, I presume) to calculate scale based on zoom level: in mapnik style, in leaflet scale bar, and in the export tab. If that doesn't confuse you, I think you are not in a target group for this issue :)

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Reply to this email directly or view it on GitHub:
https://github.com/openstreetmap/openstreetmap-website/issues/368#issuecomment-21305608
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