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Comment by jamessb

5 years ago

It is a very literal encoding: the colors are the actual colors of the lights (unless you uncheck the "Show real colors" checkbox), they flash in the same pattern as the actual lights, and the radius of the circles is proportional to the nominal visible range (but I think they are smaller than the actual range [1]).

[1]: https://github.com/geodienst/lighthousemap/pull/9

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jamessb

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ygra  5 years ago

Considering they're circles on a Mercator projection, they can't be the actual range, or at least they'd be off in at least one direction.

  • jamessb  5 years ago

    Yes, but they're relatively small so circles are not too bad as an approximation.

    The Leaflet.Geodesic plugin can render (polygonal approximations to) geodesic circles correctly. Based on playing around with this demo [1] (drag the central marker to reposition, and drag the outer marker to resize), I don't think the deviation from circles would really be noticeable for most of the lights.

    (Edit: some lights may only be illuminated in a particular sector, and there may obstacles blocking the view in some directions - arguably both of these are far more significant problems with the use of circles as markers)

    [1]: https://blog.cyclemap.link/Leaflet.Geodesic/circle-interacti...