[Talk-us] US highway classification

[Nathan Edgars II]

On 5/29/2011 2:30 AM, Nathan Mills wrote:
> I think that trunk is more useful if it's prescriptive, more along the
> lines of a motorway than primary and below. If we aren't going to do
> that, we need to come up with another value for highway and get it
> rendered by default. It's something that map users expect, and we should
> therefore deliver.

How many maps actually show these with a separate symbol, though? 
Looking through my 1990s road atlases, AAA and National Geographic 
(MapQuest) simply modify the symbol, keeping the color of the two-lane 
segments, while Rand McNally and Gousha (RIP) use one symbol for all 
divided highways, no matter how important (in Orlando, this includes 
Colonial, 17-92, OBT, and Michigan). (All four count center turn lanes 
as medians - see South OBT.) Unless you're proposing to mark all divided 
highways, rural and urban, as trunk, map users accustomed to road 
atlases won't expect your criteria.

Perhaps the best way to handle it would be to render a wider line if 
oneway=yes and not lanes=1 or if oneway=no/unset and lanes=4 or more. 
Thus divided highways would not need a lane count to be wider, but 
undivided roads would need to be tagged as having four lanes.