Best map editing practice (especially Railroads)

[porubcan]

hello all,

I was trying to find more information regarding non-drivable segments (railroads in this case, but we may generalize the topic)

I think correct handling of non-drivable segments should be added to Best map editing practice

e.g. if (or when) create junctions when connecting/crossing, which direction settings are most appropriate, segment naming, etc.

thanks

[Kuhlkatz]

You mean like this US section ?
I think it was meant to be handled individually by each country.
What should likely be clearly stated everywhere else is that it should NOT be connected to the current road grid at all.

The main question is, if it's not drivable, what's the use of setting turn restrictions ?
Would anyone riding in a train want instructions to turn left ? It's not likely that they would be routed on there by the routing engine in the first place.

[porubcan]

I was wondering, if there is any general rule, it should be in general wiki section.

I personally see good reason to have railroads crossing with junction and I already started discussion about railroads in Editing Experts forum. within this discussion there is one point regarding the junction on railroad crossings (following is my own opinion, which was disregarded by other Experts):

when railroad and normal road are crossing, we should take this junction in count for routing (penalty) and for traffic analysis (if there is slow traffic before the crossing, it doesn't mean real jam, but just train passing by and traffic is going back to normal after short time period.

also there are different avg. speed values before and after crossing so it makes sense to have the junction dividing the road segments.

so I tried to find any relevant rules on wiki, but haven't.

[kentsmith9]

I would say that routing will still work fine regardless if the junction is at the railroad crossing or not. Consider what the routing server will see without the junction. If trains crossed every 10 minutes for 5 minutes total, the segment it crossed (but did not join) would have an average speed of a much lower number than the segment one block away that had an underpass/overpass. It does not matter if the junction sits on the railroad or not to get the same routing time through that area.

Therefore you do not need to add complexity with junctions and turn restrictions at the point of a railroad crossing. If anything we might want to add the above explanation to help people understand why not to create the junction there.

[kentsmith9]

I went ahead and added content to http://www.waze.com/wiki/index.php/Road ... 9#Railroad per our discussion so far. If we decide to change our best practices recommendations we can do so.

I also created redirects to this same wiki entry for:
* Railroad
* Railroads
* Railroad crossing
* Railroad crossings

While these do link to the US Road Types page, I added a link back to the international list at the end of the Railroad instructions.

[AlanOfTheBerg]

I made an update to the Turn Restrictions section to update images and add some verbiage about u-turns.