Google Directions API会在一次请求时生成多个路径

Question

My app has to calculate distances on the roads for every POI in the list (about 80 POI). When user change his location this distances must be recalculated for current user location. My question is how i can put all my POI coordinates to one Google Directions API request?

Answer 1

Google Distance Matrix API specifically is used to calculate distance between multiple points.

However there are certain limits on how many elements you can request in a call depending upon the account you hold with Google.

Standard Usage

If you have a regular account the limit is 100 elements per call/second and also a cap of 2500 free elements per day. After this you will be charged per element if you have payment enabled. Even though documentation specifies that the maximum number of origins and destinations is 25, there is no strict implementation on this. The call to Google Distance Matrix API will work good as long it is within the limit of 100 elements (it can be one origin with 100 destinations and vice versa).

Premium Usage

If you have a premium accounts the limit is 625 elements per server side call and 100 elements for client side call. You get a 100k free pool of elements per day with your premium account. The number of destinations and origins holds as same as standard usage and it will work as long as it is within the 625 element limit.