The three commonest problems with Traffic Icons calls are:
- Using the incorrect projection value for your coordinates. This API defaults to EPSG900913, so if you are making requests with latitude and longitude, you must tell it explicitly.
- zoom parameter set to greater than 6. Traffic incidents are not returned for zoom levels 0 - 5. There would be too many incidents per call to do so.
- boundingBox is too large. There is an internal limit to the size of bounding box that can return any traffic incidents, for performance reasons. If your projection is right (and where you think it should be) and your zoom level is OK, try using a smaller bounding box to see if you get incidents that way.
If you have checked all three of these issues and are still not getting traffic incidents, post a sample call via Contact Us form and the TomTom Developer Relations team will investigate.
Yes, caching data on the individual client app is an excellent way to improve response time and it is encouraged. You are not allowed, however, to cache the data on a central server and serve that to your clients.
No. Our traffic tiles are only available via an API call. We do offer the same information as a bulk feed. Please contact the TomTom sales team for further details on this product via Contact Us page.
There are pre-set styles available for the various tile types and the traffic incident tiles and traffic flow tiles. There is no facility to create or edit the styles provided.
There is no facility to filter traffic incidents by location. You can define a bounding box that covers the specific location (for countries, the HD Traffic Regions call provides one). Note that if the target location is not rectangular in shape, incidents that are outside of it but in the bounding box will be included in the call.
The Traffic Model refreshes every two minutes. The Traffic Icons will return the current ID, along with the current traffic information if it's given an old model ID. Traffic layer calls to the Traffic Tile API that use out of date traffic models return a 500 error code.
Production key holders will be given advance notice before the Map Kit Traffic API is withdrawn from use, and assistance with the migration to Traffic API's will be available.
The traffic situation is changing all the time. In order to deliver traffic information that's consistent enough to use in multiple API calls, TomTom creates periodic "snapshots" of traffic. Calling your interfaces with the same traffic model ID ensures that the data is consistent for a whole screen full of tiles, or for a traffic tile and an incident list. You can obtain the current TrafficModel ID from the Traffic Icons and Viewport API calls.
If you are calling multiple APIs and want all of the information coming back from them to be consistent, you should use an explicit TrafficModelID. Otherwise, you may end up with a "patchwork" effect with traffic tiles, or situations where the traffic incident descriptions do not match the visual data returned.
When the zoom level is distant, the API returns traffic incidents grouped into clusters, to allow for display in very small map space. The way that nearby incidents are grouped into clusters is determined by the zoom level.