Route calculation cost money. We constantly try to manage costs in such a way that we can continue to give you our services for free and keep them available for all users. So we have implemented various ways of throttling the number of requests, and making sure that route generation runs smoothly for all our users.
Automatic calculation is done for trips with less than a certain number of waypoints. That number can be adjusted, and the updated number is always displayed on this site.
Automatic calculation will be run whenever you have done changes to your trip, added waypoints, deleted waypoints etc. But it will be delayed a few minutes, until after you have done the last change. We do this to avoid generating a new route for every single cache when you add several caches within a short time frame.
Automatic throttling of automatic calculation
We have a limited amount of daily credits available (route calculations costs credits, complex routes cost more). So we monitor the usage closely, and if the usage is too high compared to the number of credits we should have available at any given time of the day (we divide them out over the day, and measure the current load compared to the remaining minutes until we get new credits), automatic calculation will be temporarily halted.
Warning when throttling is activated or your waypoint count is too high
When the automatic routing is stopped for some reason, you will be presented with a warning text above the map. If automatic route calculation is active and running, the text will be green.
Manually disable automatic calculation
You can also manually disable automatic calculation. Simply click on the arrow next to the status text, and select Disable automatic route calculation
You can order a new route calculation manually, even though throttling is activated and automatic route calculation is turned off, simply by clicking on Order new route calculation in the menu shown above, or in the Edit trip menu.
We get our route data from GraphHopper API, which uses data from OpenStreetMap.
Calculation of optimal route (TSP)
Solving the traveling salesman problem is expensive. Which is one of the reasons why we don't do it automatically.
You are only able to use this with up to 80 waypoints, but you can optimize several times, and in that way make it work on a larger trip.