Make requests for direction from Google's servers, and receive them in a Ruby-usable object.
To install:
sudo gem install server-side-google-maps
Then, to use within Ruby:
route = ServerSideGoogleMaps::Route.new(['Montreal, QC', 'Ottawa, ON'], :mode => :driving)
# Origin and destination accept [lat,lon] coordinates as well as strings
# :mode => :driving is the default. Others are :bicycling and :walking
route.status # 'OK'
route.origin_address # 'Montreal, QC, Canada'
route.origin_point # [ 45.5086700, -73.5536800 ]
route.destination_address # 'Ottawa, ON, Canada'
route.destination_point # [ 45.4119000, -75.6984600 ]
route.path.points # Array of Point coordinates of route
route.points[0].latitude # .latitude, .longitude, .distance_to_here
route.distance # 199901 (metres)
# We can also find elevations along a path
path = route.path
path.elevations(20) # Array of equidistant Points, each with an elevation
# Paths used for elevation may only be up to around 230 points long,
# to comply with Google's URL length limit. That's not hard to achieve:
simple_path = path.interpolate(230) # will create a new Path by interpolating
One final :mode is :direct, which calculates points and estimates
distance without querying Google. To ensure Google isn't queried, input
the origin and destination as latitude/longitude coordinates.
As per the Google Maps API license agreement, the data returned from the Google Maps API must be used only for display on a Google Map.
I'll write that again: Google Maps data is for Google Maps only! You may not do any extra calculating and processing, unless the results of those extra calculations are displayed on a Google Map.
There are also query limits on each Google API, on the order of a few thousand queries each day. Design your software accordingly. (Cache heavily and don't query excessively.)
Each feature and issue must have a spec. Please write specs if you can.