jondrush wrote:I don't care about total length of road on map, why would anyone? I only care about segment count, junction complexity and naming complexity. Two-way ramps are typically the simplest regions of the ramp, straights and simple bends... Why do we care about flaky GPS on close ramps? There is only one solution to a ramp, you get on, you get off...
The "why" is that you get many of the same problems that arise when a road is too narrow to justify splitting it:
- visual clutter of parallel segments that are only a few feet apart
- the need to adjust the geometry of two segments instead of one
- recalculations when it looks like you are headed back onto the highway, resulting in URs
- GPS tracks that look like you're headed the wrong way on a one-way segment, resulting in MPs.
When we had a splitting tool I would adjust geometry once, then split. I've made a request of Waze to see if we can somewhat duplicate this functionality.
Considering how widely it was misused in Cartouche, I don't think making a "split two-way road" feature available to the WME world would be advisable, unless they figure out a way to undo it just as easily.
Every junction is a calculation that the routing server has to make. One-way to two one way is one decision. Two-way adds three decisions, at least.
The only difference in the example I provided, as far as the routing server is concerned, is the junction where the off- and on-ramps for Route 128 meet the two-way segment. Approaching that junction in either direction, only one turn is possible. So it adds the one-time fixed cost of one additional junction look-up; it does not add a new branch to the routing tree.
Also more ways for the editor to get it incorrect.
We can spend all day weighing the relative merits of storing an extra junction vs. storing two parallel sets of geometry nodes, of the possibility of an editor overlooking a turn restriction vs. the accuracy of smartphone GPS. The bottom line is, responsibility for this corner of the map tends to land on my shoulders; and I believe mapping it this way--which I find easy, reliable and effective, or I would have done it differently--is within the discretion allowed by the editing guidelines.