I am looking for a web-based mapping service that allows linking to:
- a (geographical world) map
- at a custom zoom level on a custom location
- with a custom amount of simple overlays that must include
- placemarks at custom locations
- arrows between any two locations
Zoom level, zoom focus location, locations of any displayed placemarks, and location pairs of any displayed arrows must be specified by HTTP-GET parameters (i.e. as a part of the URL).
(for an example of what this could look like, see below)
- The ability to specify a human-readable name for each specified location is not required, but is a plus.
- It is sufficient if locations can simply be specified in geo coordinates. The service can, in addition, support named locations (e.g. city names), but that is not a requirement.
- Alternatively to the zoom level and the location, specifying a rectangle of geo-coordinates that must be visible would be fine, too.
- A web-based form to input coordinates and generate the link is nice, but by no means necessary.
Use case: Frequently, when describing something geographical (in chat, in forums, on Travel SE, ...), I feel the desire to support the explanations with a link that, when clicked, shows exactly the location, locations, or displacement I am talking about.
As far as I could find out, the common map services such as Google Maps, Bing Maps, or OpenStreetMap usually offer embeddable widgets, to which placemarks can be added by means of scripts, and also sometimes customizeable map layers so you can pre-configure your placemarks, save them on the server, and then link to that saved map. I am looking for a service that provides a very simple version of this, but "ad-hoc", in a way that nothing is stored, prepared, or procedurally modified by user scripts, but just displayed based on the information provided in a single link.
An example of what I imagine: When writing a text like
When travelling from Shanghai to Bangkok, Beijing and Ulaanbaatar both mean a significant detour.
I would like to add a link like
This link should then lead to a marked map, somewhat like this:
(This map uses OpenStreetMap data. As far as I understood the legal requirements, I need to declare this image to be public domain to be on the safe side - so be it, I hereby do.)
Finally, of course, this service should be available for free. Otherwise, it would not make much sense, as anyone who sees the link should be able to follow it, and a link in a public place cannot contain any confidential credentials.