[mkgmap-dev] [PATCH] Access destination tag

Sun Mar 1 19:16:32 GMT 2009

Hi Robert,

> That's quite interesting! In my experiments, the access flags for  
> "delivery" and "emergency" didn't behave like the other six, so if  
> "delivery" is actually "destination", that'd be great.

Yes, it would be great but do we actually know if the garmin is capable of
avoiding routing into an area if the destination is not within that area?

At this time, I can't picture how the gps could work it out. It would have
to make nets of connected ways that all have that attribute to be able to
route into that area - it seems to be (potentially) very complicated.

> For the record, calling these fields DELIVERY and EMERGENCY has to do  
> with the cGPSmapper documentation: The RouteParams field ends in 8 bit  
> flags which are named according to the vehicle types. We're assuming  
> these 8 fields actually correspond to one byte in the IMG. This may be  
> off, or the cGPSmapper may be inaccurate.
> 
> But having flags "no delivery" or "no emergency vehicles" on a road  
> doesn't make too much sense.

No, but having a flag "delivery allowed" or "emergency allowed" does -
imagine a pedestrian area that doesn't allow normal traffic but does
allow delivery vehicles and could be used by emergency vehicles. Such
areas exist, I have seen them.

More thinking required...

Cheers,

Mark