What is the meaning of... enforceShortestPath?

[Bernd Welter]

Hello together,

these days a contact asked us for "what is the meaning of the parameter enforceShortestPath in the xml routing profile?"...

OK, here is some little description...

While the regular parameter OPTIMIZATION (also known as distanceTimeWeighting ) is some kind of linear balance between

• driving distance (values around 0)
• driving period (values around 100)

the enforceShortestPath parameter is a mechanism with much bigger impact as you would expect. Therefore I'd like to inform and warn you about what it really does... please be careful with it's usage:

• it sets all MalusByNetworkClass to 0 (i.e. there is no difference in the preference of a highway versus any other street category)
• the LevelingScope for each network class is set to -1 (i.e. which means the routing algorithm considers EVERY street segment in the map even if it is a small LEVEL6 road far away from any included WaypointDesc). This has a HUGE impact on performance and in most cases this behaviour is not really necessary!

Please try to recognize what this parameter means and handle with care not to open pandora's box
We recommend to solve the shortest paths by using proper values for parameters such as

• MalusByNetworkClass
• UrbanMalus
• ResidentialMalus
• and so on...

Furthermore the OPTIMIZATION should use values between 20 and 80 percent... values outside this interval may cause strange side effects such as ferry hopping


Best regards Bernd