User:Kartografer/Far lanes

This junction box, which is necessary southbound-to-northbound U-turn prevention, has far lanes on all six far turns from eastbound Veterans Blvd. This gives preferred lanes for the right turns and the combined lane picture to both left and right turns.

Simple lane guidance works well for in many places, but not all of them. Far lanes were developed in order to provide editors greater control over unusual and complex lane situations.

Far lanes can be added by rank 4 and higher editors. They can be added to the far turns in junction boxes (known as far lanes phase 1, FL1), and in paths (known as far lanes phase 2, FL2). Although junction boxes and paths have some differences, far lanes work identically whether in a path or junction box connection.

They can enhance lane guidance in at least one of two ways, and often both at the same time.

Preferred

Preferred lanes show drivers that they should use a particular lane or lane(s) that are a subset of the lanes involved in a turn. For example, there may be two lanes that turn left at an intersection, and then the two lanes split immediately in two different directions. If a driver's route is to turn left, then immediately turn left again, the driver should be given only the leftmost lane of the first turn.

Combined

Similar to the heuristics used to combine the lane guidance for separate turns through H and # intersections, far lanes can be used to ensure that a complete lane picture is shown at every turn through an intersection with multiple nodes and segments. The turns at multiple nodes in a single intersection are tied together, just like the heuristic lane combination behavior for H and # intersections, but with fewer restrictions and better control by editors. This is especially useful where an intersection has at-grade connectors, or its geometry is skewed too much from perpendicular to meet the requirements for lane-combination heuristics to work.

50-meter rule

Far lanes are only combined for an intersection, or "pushed" past the first node to the next turn, if they meet certain criteria. These are:

• No turn instruction may be given at the first node (otherwise, the far lanes would just show there).
  • Voice prompts and "view & hear" straight lanes are considered, both on near and far turns.
• The distance to first turn that has an instruction must be less than 50 meters (164 feet).
• No lane guidance may be present on the segment immediately before the instruction.

If far lanes are pushed, any visual turn instruction, TTS or voice prompt set on the far turn is also pushed to the location of the next turn. This can cause some unexpected results, so be sure to understand where an instruction will be displayed when using far lanes.

If the criteria for the 50-meter rule are not met, and there is no full turn instruction on the first node of the junction box or path connection, any non-straight far lanes will be displayed at the first node with "continue straight text" under them, just like "view only" straight lanes. This can also cause unexpected results, since a turning lane arrow with "continue straight" under it often appears self-contradictory. Be sure to understand this effect, and if single-intersection far lanes behavior is desired, try to adjust nodes to fit, while making sure to retain realistic geometry.

Note that a segment may not support both divided-road heuristic combination and far lanes in the same direction. If you decide to add far lanes to an intersection that has the older heuristic combination, be sure to remove any subsequent lane guidance on the median segment and, if applicable, past the AGC. The far lanes must be on the segment that enters the intersection.

Guidance

Since the 50-meter rule is satisfied, this combined lane picture is shown at both left and right turns. Preferred lanes are given for the left turns that have immediate next turns south of this intersection.

Use far lanes when necessary to provide one or both of the following benefits:

1. More complete lane guidance at multi-node intersections that divided-road heuristics cannot combine.
2. More specific, preferred lane guidance through a junction based on a later turn.

For combined lanes the question simply revolves around what constitutes a "single intersection." If unsure, check street view and imagine if you as the driver would see all the roads meeting together as one large intersection or not. Check lane signage and pavement markings and try to match Waze to what the driver sees. The basic cases are # or H intersections, intersections with at-grade connectors, and combinations of the two.

Preferred lanes should be set for any multi-lane movement where you're already getting an instruction and where the best lane to choose at the movement depends on which movement you're going to make next. Any time you have two or more lanes going through the same turn, exit, or keep, you should consider preferred lanes. Look for applicable later movements which are close enough to make a difference in which lane to be in earlier. A good yardstick is "within about the next minute" for whether a later movement is close enough to need preferred lanes. This means about 1 mile on a 60-mph freeway, much shorter at surface speeds; use your best judgment.

The view only far lanes not only show the correct lanes for each part of the 2nd exit as of the 1st exit but also suppress the "use the right lane to" part of the TTS instruction for the 2nd exit until you actually pass the 1st exit.

Another valid use of preferred lanes is where you wouldn't have otherwise received an instruction. For example, if you have two freeway exits on the same side about a mile or less apart, and the first one has an exit-only lane of any kind, then a view only straight at the first exit for the second exit's lane(s) can be very helpful. If the second exit is multi-lane, you can even use that view-only to direct people into the correct lane for the 2nd exit.

This can also be done at a smaller scale on surface streets; if you have a series of hard to predict turn-only lanes then drivers can use the help.

Editing notes

Make sure that all the boxes for the lanes are checked somewhere, either in near turns or far turns or both, and that everyone going through gets at least one lane. This lane guidance is correct, even if the left lane is not applied to a near turn. The junction box is used for U-turn restrictions.

If you see this tooltip after saving, your lanes are invalid and need to be fixed before they will show in the app.

Far lanes may only be added to far turns on junction boxes and paths. There are a few things to take note of:

• As of February 2023 there is no automatic assignment of lane directions to far turns as to near turns; the lane arrows must be set manually.
• Make sure to set far lane arrows based on what the driver sees around the end of the segment selected; far turn arrows merely show which routes the turn information applies to, not where the lanes are shown in the app during the drive.
• Lane guidance will be shown only if every lane is populated either in near or far turns or a combination of both, and if the lane guidance is validated by the system during a save.
• After saving, make sure that the lane guidance does not have any error indicators.
• It is not always necessary to assign lanes to near turns, if you have lanes on far turns, but it is good practice.
• The LaneTools script indicates errors in lane guidance if not all lanes are assigned to near turns, but this is inevitable in many situations with turn lanes, such as in the example at right.

Far lane resources

• Waze staff how-to document for phase 1 far lanes (junction boxes)
• Waze staff how-to document for phase 2 far lanes (paths)
• Waze staff (Gil) office hours presentation on JB far lanes
• Waze staff (Gil) office hours presentation on path far lanes
• WME far lanes recorded demo by whoaitspete (US Champ)