I've been looking into this for quite a bit, but couldn't find a solution. Is there a way to find out whether railway tracks are near a users position?
The APIs don't provide a places search like this (see Google Places supported types for this). One possibility would be to download the OpenStreetMap dataset for your region, import it in a database and extract the datasets Railways. Then you could pass the users position to your database (PostGIS) and check if there is a railways matching your filters.
Moreover there is the OpenRailwayMap, if you just need a possibility to do some visual identification of railway tracks. See OpenRailwayMap API site for further usage information.
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I am working on a GSM based tracking device . i have successfully able to plot the approximate location on google maps using Gmap.net library for windows application and google maps api for android application.I want to mainly do the tracking of the Rail coach .with my current device i gets the approximate location near the railway track.I want to shift that Location /Maker on the near by Rail track.i need help and suggestions on how to achieve this task.please help.
Afaik the gmap.net library does not provide any feature around pinning tracking data, so I guess some manual work might be necessary.
The naive approach is to map your track on your own, google maps etc. is fine. I fact I've used gmap.net once itself to create exactly that.
Then all you need to do is some math (useful key word here is 'shortest path'), to locate the closest matching tracking point and use interpolation to distinguish your anticipated position on the track. You can also add some plausibility checks to speed up the whole process such as "knowing" where on your track you've already been.
I've got experience in real-time tracking for TV events and can go in deeper detail if you want.
I am developing a node.js application which (amongst other things) will recieve location information from remote users and allow them to interact with each other via the server.
I'm using the Google Tracks API because I like the idea of being able to track users when appropriate, set up geofencing to define my coverage areas and to visualise what's happening.
The Google tracks API documentation is reasonable, however I'm not sure how I would go about actually visualising the entities and geofencing I have setup on a map - this is not something that I can find covered elsewhere.
Ideally I would be able to simply embed a map into a webpage which could link with my Tracks API account and show all of the fencing and entities. Another nice feature would be the ability to 'draw' a geofence, is there anything out there which would allow this?
Thanks :-)
Tracks API does not currently offer any kind of server-side rendering for your Tracks data, so the best approach is to use the API to retrieve the crumbs (or just current location) and render them using polylines (or just markers) in the Google Maps API. You can similarly get all your geofences and render them using polygons.
Because this is done clientside, you'll probably want to limit your data to a reasonable number (depending on the browser/OS combination, something like O(thousands) of vertices).
All this assumes that your app meets the terms of service of the Maps API so check those out as well.
I am in the process of building a booking system and I'm wanting to do a lookup, based on a text field, that searches both businesses and addresses.
For example, a user is presented with an Input Box that asks them to enter a location. I want it to support Businesses and Addresses.
My current implementation uses the Geocoding web service, but it's unable to find businesses, so I need to bring in the Places API.
I also need to find the distance between these places using the Google Distance Matrix Web Service.
I thought I'd solved my problem by JUST using the Google Places API, but not all addresses are listed on it.
Any ideas / previous experience is greatly appreciated.
You can use both of these on the page, and place a condition for an unsuccessful search on one (i.e. missing or empty variable) to trigger the other.
I am trying to get the distance traveled on a transit route -- particularly San Francisco MUNI, but the standards NextBus, GTFS, and Google Maps API appear to be universal. I'm comfortable using any of these APIs, I'm just not sure how to go about this problem.
The easy way - ask Google Maps (this using webservices, but there is also the javascript API):
http://maps.googleapis.com/maps/api/directions/json?origin=37.7954199,-122.397&destination=37.7873299,-122.44691&sensor=false&mode=transit&departure_time=1348109609&alternatives=true
this JSON includes distance traveled, but there are two issues:
Google does not allow you to use this data unless you're displaying a map, which I don't want to do
I would need to ensure that the distance returned is for the correct route/line, since it can/will give multiple routing options. This is probably doable but would require more logic.
EDIT: using alternatives=true (or provideRouteAlternatives: true using the javascript API) only returns a maximum of 3 routes, which here in SF often doesn't include the route I'm looking for (other transit agencies, multiple lines on the same route, etc). So this isn't such a great option.
NextBus:
example route config:
http://webservices.nextbus.com/service/publicXMLFeed?command=routeConfig&a=sf-muni&r=1
The coordinates for each stop are given, but connecting the dots on those is not the same as the route taken -- it will cut corners, etc, and I need this to be accurate. The actual route taken is given under <path>/<point>, but I don't see any obvious correlation between stop and path coordinates. Plus, NextBus says in their documentation (p.10 near the bottom) that you should NOT connect points between <path> segments, they're only meant for drawing on a map and can overlap.
GTFS:
The GTFS data also separates stop and "shape" coordinates (like NextBus paths). Unfortunately, the coordinates are slightly different for the same stops between NextBus and GTFS (rounding), though the stop ID/tags are the same. Also, the data files are in the megabytes, and I need to use this for a mobile app. I suppose I could put all the data in a database and query that, but that still leaves figuring out how to correlate the stops with the shape. The "shapes_distance_traveled" column in the shapes.txt file is especially promising. MUNI chooses to leave the optional "shapes_distance_traveled" field out of stop_times.txt, though.
Any advice would be appreciated, I understand this seems like an epic task to get a simple value. Maybe I'll just throw a map in to legitimately use the distance :)
Instead of using Google Maps, I would look into the un-encumbered licensing of OpenStreetMap. There are multiple
routing engines that can use OSM data. Personally, I would use routing in PostGIS or SQLite, but depending on your skillset you might choose another.
You've clearly done your research, (+1), and as you said, the easy way is to ask Google. If it is worth for you then you might want to look into purchasing a business licence to use the Google Maps API, and negotiate with them about the requirement of displaying a map. That's the only legal way I can think of with the Google API. Alternatively, you can try building you own routing engine with data from the TIGER data set, which is freely available from the US Census Bureau, but again, as you said, it may seem like an epic task. :-)
My objective: populate a database with known business places in order to generate maps with those places. I insist on "known places", because my users will only search for the places that are in the database.
I don't want to recreate business places as markers on the map (so latitude and longitude is not enough to id a place), because the places are already available on Google Maps with interesting information (address, comments, ratings, pictures...).
The natural reference is to use the CID and store it in the database.
Now imagine the database is populate with places and their CID, and I want to generate maps with those places as click-able markers. When the user clicks on the marker, she access the business place's page, e.g. http://maps.google.com/maps/place?cid=998657413562662319. Great!
But how to generate those maps? I don't have the coordinates in the database (assumption). And I cannot use Google Places API (which would give me the coordinates), because it uses a different reference, to retrieve the location of the business so as to generate the maps.
Any ideas?
Thanks a lot!
To clarify: I want to use Google Maps API to generate a map with many business places of which I know the CID. It is comparable to "my maps" in Google. Only that I want to store the places in my database.
Potential solution: For each business in the database, store the name, CID, and coordinates. Write a script that uses Google Places to find businesses at specific coordinates. Loop through the response array (JSON/XML) until the response with the CID corresponding to the searched business is found. Store the Google Places reference into the database. Repeat this script for each newly added business. Cumbersome...
Is this what you are looking for?
http://maps.google.com/maps?cid=998657413562662319
It looks like your best option if you want more than one cid on a map is to use:
http://maps.google.com/maps?cid=998657413562662319&q=a&output=json