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'''Falcon Map Snapper''' is a mechanism in Waze that positions the car on the user's map in relation to the mapped roads by collecting data like GPS, accelerometer, GPS speed, and more.  It was implemented in 2021 to replace an old mechanism called The Matcher, which was simple and only used GPS position in relation to the mapped roads.
'''Falcon Map Snapper''' is a mechanism in Waze that positions the car on the user's map in relation to the mapped roads by collecting data like GPS, accelerometer, GPS speed, and more.  It was implemented in 2021 to replace an old mechanism called The Matcher, which was a simpler mechanism that only used GPS position in relation to the mapped roads.


= {{@|Overview}} =
={{@|Overview}}=
=== {{@|What is The Matcher?}} ===
==={{@|What is The Matcher?}}===
As you drive along your route, the arrow in the Waze app depicts your location on the Waze map. A technology, previously called the matcher, "snaps" the arrow to a segment on the map on your route. This association is very strongly bound to keep the arrow tied to the current route. As a result, Waze has often been slow to detect and recalculate changes when you deviate from the route, especially if the new route runs parallel to the old route.
As you drive along your route, the arrow in the Waze app depicts your location on the Waze map. A technology, previously called the matcher, "snaps" the arrow to a segment on the map on your route. This association is very strongly bound to keep the arrow tied to the current route. As a result, Waze has often been slow to detect and recalculate changes when you deviate from the route, especially if the new route runs parallel to the old route.
[[File:Matcher.png|alt=Picture illustrating the concept of the Matcher and Snapper.|thumb|Illustrating the concept of the Matcher and Snapper.]]


=== {{@|What is Falcon Snapper?}} ===
==={{@|What is Falcon Snapper?}}===
Waze is launching a new feature called the Falcon Snapper, already live on Android and in beta for iOS. The new snapper is next generational – it is smarter and more predictive than the previous matcher. It uses multiple sensors (including GPS) to determine the most likely position of the car in relation to the road. Its power setting is currently turned down though. Before we can fully utilize its power, we need to make changes to our mapping standards and the Waze map. Once we finish, the power setting on Falcon can be turned up to the max!
The new Falcon Snapper is next generational and replaces The Matcher. It is smarter and more predictive than the previous matcher. It uses multiple sensors (including GPS) to determine the most likely position of the car in relation to the road. Its power setting is currently turned down though. Updates to our mapping standards have occurred, guiding editors in how to edit the Waze map to fully utilize the power of Falcon Snapper.


=== {{@|Falcon Snapper Mapping Principles}} ===
==={{@|Falcon Snapper Mapping Principles}}===
The community is leading the way in upgrading the Waze map to meet the new requirements of Falcon Snapper. We therefore need to change our thinking to these new principles:
The community is leading the way in upgrading the Waze map to meet the new requirements of Falcon Snapper. We therefore need to change our thinking to these new principles:


# The map needs to be as '''accurate as possible and representative of reality: the position of the segment on the road, and the direction / angle of intersecting segments.''' Segments that do not meet these new principles could make Falcon hiccup, switch the arrow to another segment/route, and cause a poor user experience.
#The map needs to be as '''accurate as possible and representative of reality: the position of the segment on the road, and the direction / angle of intersecting segments.''' Segments that do not meet these new principles could make Falcon hiccup, switch the arrow to another segment/route, and cause a poor user experience.
# '''We are moving away from using the map as a way to control the app.''' A map should be a map; it should be accurate and represent the world. The only time the map should deviate from reality is when an app function would be broken as a result of accurately drawing the map.
#'''We are moving away from using the map as a way to control the app.''' A map should be a map; it should be accurate and represent the world. The only time the map should deviate from reality is when an app function would be broken as a result of accurately drawing the map.


= {{@|Mapping Guidance for Falcon Snapper}} =
={{@|Mapping Guidance for Falcon Snapper}}=
What are the primary goals for optimizing the map for Falcon Snapper?
What are the primary goals for optimizing the map for Falcon Snapper?


== {{@|Realign Segments}} ==
=={{@|Realign Segments}}==
To enable Falcon to work as well as it can, segment positions need to be aligned with reality as closely as possible. To do this:
To enable Falcon to work as well as it can, segment positions need to be aligned with reality as closely as possible. To do this:


# Determine whether the satellite imagery in the area is trustworthy by comparing it with the GPS points layer.
#Determine whether the satellite imagery in the area is trustworthy by comparing it with the GPS points layer.
# If the satellite imagery is trustworthy, align the segments to the center of the roadway using the satellite imagery.
#If the satellite imagery is trustworthy, align the segments to the center of the roadway using the satellite imagery.
# If the satellite imagery is not trustworthy, align the segments to the center of the tracks in the GPS points layer as closely as possible.
#If the satellite imagery is not trustworthy, align the segments to the center of the tracks in the GPS points layer as closely as possible.


== {{@|Determine Trustworthiness of Satellite Imagery}} ==
=={{@|Determine Trustworthiness of Satellite Imagery}}==
Determining the trustworthiness of satellite imagery is a very quick check you should do any time you’re adjusting roadway geometry. It takes only seconds (especially using the default shift-G and shift-R keyboard shortcuts to quickly switch on and off the GPS points and segments layers, respectively) and can save a ton of re-work.
Determining the trustworthiness of satellite imagery is a very quick check you should do any time you’re adjusting roadway geometry. It takes only seconds (especially using the default shift-G and shift-R keyboard shortcuts to quickly switch on and off the GPS points and segments layers, respectively) and can save a ton of re-work.


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But if the arrows show a lot of traffic that is ''not'' aligned with roads visible in satellite imagery, you might have a problem.
But if the arrows show a lot of traffic that is ''not'' aligned with roads visible in satellite imagery, you might have a problem.


=== {{@|Trustworthy Imagery}} ===
==={{@|Trustworthy Imagery}}===
In this image, the bulk of the arrows are well within the limits of the roadways, without any significant concentration of arrows showing a misalignment.
[[File:TrustworthyImagery1.png|alt=Screenshot illustrating trustworthy imagery against GPS trails.|thumb|200x200px|In this image, the bulk of the arrows are well within the limits of the roadways, without any significant concentration of arrows showing a misalignment.]]
 
[[File:TrustworthyImagery2.png|alt=Screenshot illustrating trustworthy imagery against GPS trails.|thumb|200x200px|This is another example of well-aligned imagery—even though there are “junk” arrows everywhere, there are strong concentrations of arrows that line up well with actual roads, so the imagery is trustworthy.]]
This is another example of well-aligned imagery—even though there are “junk” arrows everywhere, there are strong concentrations of arrows that line up well with actual roads, so the imagery is trustworthy.
 
In cases where imagery is trustworthy, align segments with the satellite imagery.
In cases where imagery is trustworthy, align segments with the satellite imagery.


Align the segments '''as close to the center of the road as practical'''.
Align the segments '''as close to the center of the road as practical'''.


* On roads with multiple lanes, the lane lines can be used as a guide for finding the center of the road.
*On roads with multiple lanes, the lane lines can be used as a guide for finding the center of the road.
**On one-way segments with an even number of lanes, the segment should cover the line between the middle two lanes.
**On one-way segments with an odd number of lanes, the segment should run dead center in the middle lane.


* On one-way segments with an even number of lanes, the segment should cover the line between the middle two lanes.
*Generally, follow the '''geometric center''' of the road.
* On one-way segments with an odd number of lanes, the segment should run dead center in the middle lane.
**On two-way segments, the geometric center will not always be the same as the roadway centerline that splits the two directions of traffic.
**However, in cases where the geometric center of the roadway temporarily shifts near an intersection, don’t blindly “chase the turn lanes” if doing so would cause an abrupt correction at the intersection. Falcon Snapper is smart enough to know that roadways sometimes get wider near intersections. Keeping the path smooth is more important in these cases.


* Generally, follow the '''geometric center''' of the road.
When the center of the road changes abruptly due to a change in the number of lanes, keep the transitions smooth.


* On two-way segments, the geometric center will not always be the same as the roadway centerline that splits the two directions of traffic.
[[File:OneWaySegments1.png|alt=Screenshot illustrating one-way segments on top of imagery.|frameless]]
* However, in cases where the geometric center of the roadway temporarily shifts near an intersection, don’t blindly “chase the turn lanes” if doing so would cause an abrupt correction at the intersection. Falcon Snapper is smart enough to know that roadways sometimes get wider near intersections. Keeping the path smooth is more important in these cases.


When the center of the road changes abruptly due to a change in the number of lanes, keep the transitions smooth.
'''One-way Segments Example 1 (Above Left) —''' Follow the geometric center of the roadway. On the 4-lane segments, the lane markings between the 2 middle lanes are a great reference.
 
[[File:OneWaySegments2.png|alt=Screenshot illustrating one-way segments on top of imagery.|frameless|500x500px]]


'''One-way segments—'''follow the geometric center of the roadway. On the 4-lane segments, the lane markings between the 2 middle lanes are a great reference.
'''One-way Segments Example 2'''


'''One-way segments.'''
*Westbound, a transition from 3 lanes to 2 lanes & 1 lane—note the transition is smooth. For the 3-lane portion, follow the center of the middle lane. For the 2-lane portion, follow the lane markings between the two lanes.
*Eastbound upper, an easy 2 lanes, so follow the lane markings.
*Eastbound lower, a smooth transition from 1 lane & 1 lane into 2 lanes, then an exit on the right while the 2 lanes continue onward. For the 1-lane portions, follow the center of the roadway. For the 2-lane portion, follow the lane markings between the two lanes.


* Westbound, a transition from 3 lanes to 2 lanes & 1 lane—note the transition is smooth. For the 3-lane portion, follow the center of the middle lane. For the 2-lane portion, follow the lane markings between the two lanes.
<br />[[File:DontChaseTurnLanes.png|alt=Screenshot illustrating the difference between chasing turn lanes (not recommended) and not chasing turn lanes (preferred).|frameless]]  [[File:MapToCenterBeforeAndAfter.png|alt=Screenshot illustrating the difference between roads not mapped to the centerline, and roads mapped to the centerline.|frameless|314x314px]]
* Eastbound upper, an easy 2 lanes, so follow the lane markings.
* Eastbound lower, a smooth transition from 1 lane & 1 lane into 2 lanes, then an exit on the right while the 2 lanes continue onward. For the 1-lane portions, follow the center of the roadway. For the 2-lane portion, follow the lane markings between the two lanes.


'''Don’t “chase the turn lanes”—Falcon is smart enough to know that roadways sometimes get wider near a turn. “Chasing the turn lanes” leads to awkward geometry at the junction itself, which is a bigger problem.'''
'''Don’t “Chase the Turn Lanes” — Falcon is smart enough to know that roadways sometimes get wider near a turn. “Chasing the turn lanes” leads to awkward geometry at the junction itself, which is a bigger problem.'''


It’s okay to realign segments even if they are only off by a few feet or half a lane. We want our segments to be as close to reality as possible so that Falcon can work as well as possible.
It’s okay to realign segments even if they are only off by a few feet or half a lane. We want our segments to be as close to reality as possible so that Falcon can work as well as possible.


=== {{@|Non-Trustworthy Imagery}} ===
==={{@|Non-Trustworthy Imagery}}===
Imagery is not trustworthy if it is either misaligned or out of date.
Imagery is not trustworthy if it is either misaligned or out of date.


In this image, you can see a strong concentration of GPS tracks cutting through what appears to be forests and fields in satellite imagery. This strongly suggests that the roadway alignment has changed, so this imagery is not trustworthy.
[[File:NonTrustworthyImagery1.png|alt=Screenshot illustrating how the GPS trails indicate that the imagery is not trustworthy.|frameless]] [[File:NonTrustworthyImagery2.png|alt=Screenshot illustrating how the GPS trails indicate that the imagery is not trustworthy.|frameless|342x342px]]
 
In the first image, you can see a strong concentration of GPS tracks cutting through what appears to be forests and fields in satellite imagery. This strongly suggests that the roadway alignment has changed, so this imagery is not trustworthy.


In this image, you can see a strong concentration of arrows that ''do not'' line up with the roadways visible on satellite imagery, but which have the same shape as the roadways.
In the second image, you can see a strong concentration of arrows that ''do not'' line up with the roadways visible on satellite imagery, but which have the same shape as the roadways.


If the imagery is not trustworthy, segments should be aligned with GPS tracks.
If the imagery is not trustworthy, segments should be aligned with GPS tracks.


On a two-way road, you should see arrows of 2 different colors, showing 2 different directions of travel. Align the segment to the center of the two directions of travel:
On a two-way road, you should see arrows of 2 different colors, showing 2 different directions of travel. Align the segment to the center of the two directions of travel:
[[File:NonTrustworthyImagery3.png|frameless|265x265px]]


On a one-way road, you should see a cluster of arrows of the same color. Align the segment with the center of this cluster.
On a one-way road, you should see a cluster of arrows of the same color. Align the segment with the center of this cluster.


=== {{@|Bridges and Overpasses}} ===
==={{@|Bridges and Overpasses}}===
Even in areas with otherwise-trustworthy imagery, high-rise bridges and overpasses may be significantly misaligned. This is due to a phenomenon known as parallax. Because the satellite’s camera is not always directly above the places it’s photographing, anything not at ground level ''might'' not be aligned properly with things around it—while the satellite imagery provider does typically attempt to compensate for parallax error, it is not always successful. Where this error occurs, use satellite imagery to align segments at ground level, but follow the GPS tracks more closely as you near the peak of the bridge or overpass.
Even in areas with otherwise-trustworthy imagery, high-rise bridges and overpasses may be significantly misaligned. This is due to a phenomenon known as parallax. Because the satellite’s camera is not always directly above the places it’s photographing, anything not at ground level ''might'' not be aligned properly with things around it—while the satellite imagery provider does typically attempt to compensate for parallax error, it is not always successful. Where this error occurs, use satellite imagery to align segments at ground level, but follow the GPS tracks more closely as you near the peak of the bridge or overpass.
[[File:BridgesAndOverpasses1.png|alt=Screenshot illustrating how GPS trails indicate parallax in satellite imagery on elevated roadways.|frameless|400x400px]]


'''Though most of the GPS tracks in this image show that the imagery is trustworthy—even on most of the elevated ramps and freeways in this image, upwards of 100 feet above ground level—the selected reversible HOV lane segments are misaligned by a bit. While the satellite imagery provider does attempt to correct parallax errors, it’s not perfect (and the blurriness of the imagery on those elevated roadways is further evidence of this).'''
'''Though most of the GPS tracks in this image show that the imagery is trustworthy—even on most of the elevated ramps and freeways in this image, upwards of 100 feet above ground level—the selected reversible HOV lane segments are misaligned by a bit. While the satellite imagery provider does attempt to correct parallax errors, it’s not perfect (and the blurriness of the imagery on those elevated roadways is further evidence of this).'''
[[File:BridgesAndOverpasses2.png|alt=Screenshot illustrating how GPS trails indicate parallax in satellite imagery on elevated roadways.|frameless|400x400px]]


'''At the other end of the bridge, parallax error is quite evident on the elevated bridge approach segments, while the ground-level imagery is clearly trustworthy. Use the imagery at ground level; use the GPS tracks to align the bridge segments only.'''
'''At the other end of the bridge, parallax error is quite evident on the elevated bridge approach segments, while the ground-level imagery is clearly trustworthy. Use the imagery at ground level; use the GPS tracks to align the bridge segments only.'''


== {{@|Remove Fictional Doglegs and Micro-Doglegs}} ==
=={{@|Remove Fictional Doglegs and Micro-Doglegs}}==
For years, doglegs and micro-doglegs have been used for several reasons: to force turn instructions (before turn instruction overrides were introduced), to force lane arrows (before lane arrow overrides were introduced), to make junction locations stand out on the map (before the on-route turn arrow overlay was introduced), and so on. All of these reasons have two things in common:
For years, doglegs and micro-doglegs have been used for several reasons: to force turn instructions (before turn instruction overrides were introduced), to force lane arrows (before lane arrow overrides were introduced), to make junction locations stand out on the map (before the on-route turn arrow overlay was introduced), and so on. All of these reasons have two things in common:


# they are no longer valid, as the map editor and app limitations that necessitated them have been addressed with native features, and
#they are no longer valid, as the map editor and app limitations that necessitated them have been addressed with native features, and
# they can cause problems with Falcon Snapper, which is sensitive to the angle of the driver’s movements.
#they can cause problems with Falcon Snapper, which is sensitive to the angle of the driver’s movements.


'''Remember - The map needs to be as accurate as possible and representative of reality: the position of the segment on the road, and the direction and angle of intersecting segments.'''
'''Remember - The map needs to be as accurate as possible and representative of reality: the position of the segment on the road, and the direction and angle of intersecting segments.'''
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Where found, micro-doglegs should be removed, and the segments mapped with the above guiding principles, to follow more closely with reality. Add Turn Instruction Overrides (TIOs) and Lane Angle Overrides (LAOs) where necessary to provide the best driver experience.
Where found, micro-doglegs should be removed, and the segments mapped with the above guiding principles, to follow more closely with reality. Add Turn Instruction Overrides (TIOs) and Lane Angle Overrides (LAOs) where necessary to provide the best driver experience.


== {{@|Exit, Fork, Split, Wayfinder, and AGC Geometry}} ==
[[File:DoglegNo1.png|alt=Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway.|frameless]] [[File:DoglegYes1.png|alt=Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.|frameless]]
Where two roads separate from each other as in an exit, fork, split, wayfinder, or AGC, there is one guiding question: '''is there a clear straight-ahead path'''? That is, does one outbound segment clearly continue the same path as the inbound segment?


 
[[File:DoglegNo2.png|alt=Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway.|frameless|302x302px]] [[File:DoglegYes2.png|alt=Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.|frameless|335x335px]]


* Left: '''no''', there is no clear straight-ahead path.
[[File:DoglegNo3.png|alt=Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway.|frameless]] [[File:DoglegYes3.png|alt=Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.|frameless]]
* Center: '''yes''', the I-610 E outbound path is the clear straight-ahead path—even though both paths run parallel (at first), I-610 E is the actual continuation and has more lanes.
* Right: '''yes''', the left path is the clear straight-ahead path—even though these are exit ramps and there is no “continuation” per se, the left path is totally straight while the right path diverges immediately.


'''Where there is a clear straight-ahead path''',
=={{@|Exit, Fork, Split, Wayfinder, and AGC Geometry}}==
Where two roads separate from each other as in an exit, fork, split, wayfinder, or AGC, there is one guiding question: '''is there a clear straight-ahead path'''? That is, does one outbound segment clearly continue the same path as the inbound segment?


* The '''straight-ahead path''' should be more or less straight, with a smooth transition.
 [[File:NoClearStraightAheadPath1.png|alt=Screenshot illustrating a fork on a ramp where there is no clear straight-ahead path.|frameless|414x414px]] [[File:ClearStraightAheadPath1.png|alt=Screenshot illustrating an exit ramp where there is a clear straight-ahead path on the main roadway.|frameless|400x400px]] [[File:ClearStraightAheadPath2.png|alt=Screenshot illustrating an exit ramp where there is a clear straight-ahead path on the main roadway.|frameless|400x400px]]
* The '''diverging path''' should be edited as follows:


* First, place the first geometry handle of the diverging segment
*Left: '''no''', there is no clear straight-ahead path.
*Center: '''yes''', the I-610 E outbound path is the clear straight-ahead path—even though both paths run parallel (at first), I-610 E is the actual continuation and has more lanes.
*Right: '''yes''', the left path is the clear straight-ahead path—even though these are exit ramps and there is no “continuation” per se, the left path is totally straight while the right path diverges immediately.


* on freeway exits and other ramps, at the '''nearest''' point to the exit from the following:
'''Where there <u>is</u> a clear straight-ahead path''',


* If there's no solid white line, at the gore point (or “theoretical gore”, ''i.e.'', where the painted lines begin to diverge);
*The '''straight-ahead path''' should be more or less straight, with a smooth transition.
* If there's a solid white line, at its beginning;
*The '''diverging path''' should be edited as follows:
* On a multi-lane exit, at the gore point or (if present) solid white line between the inner exit lane and the main lanes of traffic;  
**First, place the first geometry handle of the diverging segment
* 1/4 mile before the gore point, on exits with a longer solid white line; or
***on freeway exits and other ramps, at the '''nearest''' point to the exit from the following:
* Halfway between the gore points of the exit and the previous exit.
****If there's no solid white line, at the gore point (or “theoretical gore”, ''i.e.'', where the painted lines begin to diverge);
****If there's a solid white line, at its beginning;
****On a multi-lane exit, at the gore point or (if present) solid white line between the inner exit lane and the main lanes of traffic; <br />[[File:MultiLaneExitGore.png|alt=Screenshot illustrating the gore point of a multi-lane exit ramp.|frameless|590x590px]]
****1/4 mile before the gore point, on exits with a longer solid white line; or
****Halfway between the gore points of the exit and the previous exit.
***on at-grade connectors, at the gore point (or “theoretical gore”).
**Next, grab the node itself, where the segments meet, and adjust the geometry of the exit itself as follows:
***If the actual path of the exit diverges from the inbound path by less than 20°, adjust the node to create a 20° departure angle. This will allow for consistent timing of exit instructions and make it easier to report closures in the Waze client.
***If the actual path of the exit diverges immediately from the inbound path by more than 20°, adjust the node such that the exit path follows its true natural departure angle.
**Ensure that the last geometry handle before the node is at least 40 feet ahead of the node, and that the second geometry handle on the diverging path is at least 40 feet beyond the first geometry handle.


* on at-grade connectors, at the gore point (or “theoretical gore”).
'''Where there <u>is not</u> a clear straight-ahead path''',


* Next, grab the node itself, where the segments meet, and adjust the geometry of the exit itself as follows:
*Adjust the inbound segment geometry to follow the true path of the inbound segment,
*Set the first geometry handles of both outbound segments at the gore point, then
*Grab the node and adjust such that the angle between the outbound segments is '''at least 15°'''.
**If following the true natural departure angles leads to an inner angle of 15° or more, do that.
**If the outbound segments are both equally straight ahead, ensure that the outbound paths at the node are essentially symmetrical.


* If the actual path of the exit diverges from the inbound path by less than 20°, adjust the node to create a 20° departure angle. This will allow for consistent timing of exit instructions and make it easier to report closures in the Waze client.
 [[File:NoStraightAheadAngle1.png|alt=Screenshot illustrating how to set up outbound segments when there is a symmetrical departure of two ramps from an inbound segment.|frameless]] [[File:NoStraightAheadAngle2.png|alt=Screenshot illustrating how to set up outbound segments when there is a symmetrical departure of two ramps from an inbound segment.|frameless]]
* If the actual path of the exit diverges immediately from the inbound path by more than 20°, adjust the node such that the exit path follows its true natural departure angle.


* Ensure that the last geometry handle before the node is at least 40 feet ahead of the node, and that the second geometry handle on the diverging path is at least 40 feet beyond the first geometry handle.
*Essentially symmetrical: yes, departure angles of outbound segments are very close (7° and 8°).
*At least 15°: yes (de-select any segments and select the node to check).


'''Where there is not a clear straight-ahead path''',
At the other end, ramps and AGCs should enter the flow of traffic smoothly and naturally. Place the final geometry handle of a ramp or AGC at the gore point as shown below, then grab the node and pull it along the road to create a smooth, natural entry angle:


* Adjust the inbound segment geometry to follow the true path of the inbound segment,
[[File:ReEntryGore1.png|alt=Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway.|frameless|687x687px]]
* Set the first geometry handles of both outbound segments at the gore point, then
* Grab the node and adjust such that the angle between the outbound segments is '''at least 15°'''.
 
* If following the true natural departure angles leads to an inner angle of 15° or more, do that.
* If the outbound segments are both equally straight ahead, ensure that the outbound paths at the node are essentially symmetrical.
 
 
 
* Essentially symmetrical: yes, departure angles of outbound segments are very close (7° and 8°).
* At least 15°: yes (de-select any segments and select the node to check).
 
At the other end, ramps and AGCs should enter the flow of traffic smoothly and naturally. Place the final geometry handle of a ramp or AGC at the gore point as shown below, then grab the node and pull it along the road to create a smooth, natural entry angle:


[[File:ReEntryGore2.png|alt=Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway.|frameless|410x410px]] [[File:ReEntryGore3.png|alt=Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway.|frameless]]


Smooth re-entry. Just like the Apollo guys did back in the day.
Smooth re-entry. Just like the Apollo guys did back in the day.


== {{@|Dividing roads}} ==
=={{@|Dividing Roads}}==
As a “rule of thumb” - when there is a physical divider between the road (e.g. a small wall, grass, trees) and you cannot cross in a typical car, then '''map it with parallel one-way segments''' to more accurately represent reality.
As a “rule of thumb” - when there is a physical divider between the road (e.g. a small wall, grass, trees) and you cannot cross in a typical car, then '''map it with parallel one-way segments''' to more accurately represent reality.
[[File:DividingRoads1.png|alt=Screenshot illustrating a road with a physical divider that would need to be divided on the map.|thumb|Screenshot illustrating a road with a physical divider that would need to be divided on the map.]]


=== {{@|When To Divide a Road}} ===
==={{@|When To Divide a Road}}===
A road should be divided when any of the following conditions are met:
A road should be divided when any of the following conditions are met:


* It is an Interstate Highway, other freeway, or other controlled- or limited-access road with separated directions of travel, or
*It is an Interstate Highway, other freeway, or other controlled- or limited-access road with separated directions of travel, or
* There is a physical median or other traffic control device which makes it impossible or illegal to turn left onto or off of the road, including but not limited to where
*There is a physical median or other traffic control device which makes it impossible or illegal to turn left onto or off of the road, including but not limited to where


* Houses, businesses, or other destinations are located directly on the street but are not accessible from the opposite direction of travel due to a median or other traffic control device that either physically or legally prohibits such access, or
*Houses, businesses, or other destinations are located directly on the street but are not accessible from the opposite direction of travel due to a median or other traffic control device that either physically or legally prohibits such access, or
* U-turns are required for proper navigation to or from side roads or destinations.
*U-turns are required for proper navigation to or from side roads or destinations.


=== {{@|When Not To Divide a Road}} ===
==={{@|When Not To Divide a Road}}===
A road should not be divided when any of the following conditions is met:
A road should not be divided when any of the following conditions is met:


* There is a shared two-way center turn lane (of any width) between the directions of travel, or
*There is a shared two-way center turn lane (of any width) between the directions of travel, or
* It is both possible and legal to make a left turn across the roadway centerline at any point along the road (''e.g.'', across a normal double yellow line to enter a driveway).
*It is both possible and legal to make a left turn across the roadway centerline at any point along the road (''e.g.'', across a normal double yellow line to enter a driveway).


This is expected to create a lot more H and # (hash) junctions. Where they’re complex, junction boxes may be required. See junction boxes below.
This is expected to create a lot more H and # (hash) junctions. Where they’re complex, junction boxes may be required. See junction boxes below.
Line 170: Line 183:
You must consider U-turn prevention and take measures to allow or disallow U-turns where possible or impossible. To prepare for turning off the old U-turn prevention, junction boxes should be used instead of [[Junction Style Guide/Intersections#Avoiding%20U%20turns%26sa%3DD%26source%3Deditors%26ust%3D1629824825725000%26usg%3DAOvVaw3zOLo%20zf%20k5gnVVkGNwVMj|prior guidance]] that will be deprecated.
You must consider U-turn prevention and take measures to allow or disallow U-turns where possible or impossible. To prepare for turning off the old U-turn prevention, junction boxes should be used instead of [[Junction Style Guide/Intersections#Avoiding%20U%20turns%26sa%3DD%26source%3Deditors%26ust%3D1629824825725000%26usg%3DAOvVaw3zOLo%20zf%20k5gnVVkGNwVMj|prior guidance]] that will be deprecated.


== {{@|Junction Boxes}} ==
=={{@|Junction Boxes}}==
With the creation of a lot more potentially complex junctions and accurately matching roads to reality, there may be a need to add junction boxes to the intersections, or sets of intersections, you’re creating.
With the creation of a lot more potentially complex junctions and accurately matching roads to reality, there may be a need to add junction boxes to the intersections, or sets of intersections, you’re creating.


A junction box should be used when necessary to:
A junction box should be used when necessary to:


* Prohibit an illegal or impossible path that cannot be prohibited with a simple turn restriction;
*Prohibit an illegal or impossible path that cannot be prohibited with a simple turn restriction;
* Prevent illegal U-turns at H and # intersections;
*Prevent illegal U-turns at H and # intersections;
* Enable collection of differential traffic data at # and H intersections (i.e., enable the routing server to tell the difference between left turn and straight-through delays);
*Enable collection of differential traffic data at # and H intersections (i.e., enable the routing server to tell the difference between left turn and straight-through delays);
* Enable collection of differential traffic data where traffic backs up past junction nodes before the intersection (''e.g.'', because of another intersection, at-grade connector (AGC), exit ramp, or parking lot road) where the backup timing is expected to be different depending on which way the driver eventually exits the intersection; or
*Enable collection of differential traffic data where traffic backs up past junction nodes before the intersection (''e.g.'', because of another intersection, at-grade connector (AGC), exit ramp, or parking lot road) where the backup timing is expected to be different depending on which way the driver eventually exits the intersection; or
* To better collect traffic data on intricate intersections.
*To better collect traffic data on intricate intersections.


If a junction box is needed, make sure it is the last thing that needs to be done. Once added, the JB needs to be deleted for certain modifications to the segments and nodes beneath it (most notably, nodes under a JB cannot be moved, and segments connected to a JB cannot be cut).
If a junction box is needed, make sure it is the last thing that needs to be done. Once added, the JB needs to be deleted for certain modifications to the segments and nodes beneath it (most notably, nodes under a JB cannot be moved, and segments connected to a JB cannot be cut).
Line 185: Line 198:
In the United States, Level 4 and above can add/modify junction boxes. If you add one, please note on the Map Raid sheet. If you think one is needed, but you’re unable to add it, please note on the Map Raid sheet.
In the United States, Level 4 and above can add/modify junction boxes. If you add one, please note on the Map Raid sheet. If you think one is needed, but you’re unable to add it, please note on the Map Raid sheet.


== {{@|Mapping of Dedicated Turn Lanes / [[At-grade connectors|AGCs]]}} ==
=={{@|Mapping of Dedicated Turn Lanes / [[At-grade connectors|AGCs]]}}==
Do dedicated turn lanes and at-grade connectors (AGCs) need mapping? In exceptional cases only.
Do dedicated turn lanes and at-grade connectors (AGCs) need mapping? In exceptional cases only.


In the below example, note the points A and B. Falcon Snapper has a feature called “curver” which expects drivers to turn in a curve between these two points. Curver stops at geometry handles, so be sure to minimize them close to intersections. Also note that the islands created by the AGCs are small and do not result in much of a delay in the final turn instruction.
In the below example, note the points A and B. Falcon Snapper has a feature called “curver” which expects drivers to turn in a curve between these two points. Curver stops at geometry handles, so be sure to minimize them close to intersections. Also note that the islands created by the AGCs are small and do not result in much of a delay in the final turn instruction.
[[File:AGC1.png|alt=Screenshot illustrating islands at an intersection for discussion of the Falcon Snapper's curver feature.|frameless|651x651px]]


An AGC is indicated if it:
An AGC is indicated if it:


# Red arrow: creates a large island, where, without the AGC the late turn instruction will result in the driver missing the turn.
#Red arrow: creates a large island, where, without the AGC the late turn instruction will result in the driver missing the turn.
# Green arrow: geo nodes are required close to the actual turn to shape the road to match reality that affect the Falcon Snapper curver ability.
#Green arrow: geo nodes are required close to the actual turn to shape the road to match reality that affect the Falcon Snapper curver ability.
# The AGC contains essential wayfinder information.
#The AGC contains essential wayfinder information.
 
= {{@|Suggested Scripts}} =
The following scripts may be helpful for updating the map in support of Falcon Snapper:


{| class="wikitable"
[[File:AGC2.png|alt=Screenshot illustrating an AGC with a large island and curvature of a main road close to the junction.|frameless]] [[File:AGC3.png|alt=Screenshot illustrating a large island at an intersection which would require mapping of an AGC.|frameless|508x508px]]
|-
|'''WME Junction Angle Info (JAI)''' || Display angles at junctions. || [https://www.waze.com/forum/viewtopic.php?f=819&t=61926 forum] 🔗 || [https://greasyfork.org/en/scripts/35547-wme-junction-angle-info installation] 🔗
|-
|'''WME Lane Tools''' || Display lane guidance during dividing. This includes R2 so they can see where their edits can affect it and ask for help adding it back. || [https://www.waze.com/forum/viewtopic.php?f=819&t=301158 forum] 🔗 || [https://github.com/SkiDooGuy/WME-LaneTools/raw/master/WME-LaneTools.user.js installation] 🔗
|-
|'''WME Street View Availability''' || Can be used as a clue on determining if a road should be divided. || [https://www.waze.com/forum/viewtopic.php?f=819&t=180148 forum] 🔗 || [https://greasyfork.org/en/scripts/17112-wme-street-view-availability installation] 🔗
|-
|'''WME GIS Layers (GIS-L)''' || Can help with determining centerlines. || [https://www.waze.com/forum/viewtopic.php?f=819&t=249027 forum] 🔗 || [https://greasyfork.org/en/scripts/369632-wme-gis-layers installation] 🔗
|-
|'''WME Fix UI''' || Can be used to shift Aerial imagery and to move the GPS points layer below the segment layer. || [https://www.waze.com/forum/viewtopic.php?f=819&t=191178 forum] 🔗 || [https://greasyfork.org/en/scripts/20077-wme-fix-ui installation] 🔗
|-
|'''WME Locksmith''' || Properly lock segments after dividing. This includes R2 who can use it to highlight incorrect locks and ask for assistance. || [https://www.waze.com/forum/viewtopic.php?f=819&t=285583 forum] 🔗 || [https://greasyfork.org/en/scripts/386773-wme-locksmith installation] 🔗
|-
|'''Straighten Up!''' || Can remove excess geometry handles if ToolBox isn’t installed (only select a single segment). || [https://www.waze.com/forum/viewtopic.php?f=819&t=289116 forum] 🔗 || [https://greasyfork.org/en/scripts/388349-wme-straighten-up installation] 🔗
|-
|'''Color Highlights''' || Highlighting Tool || [https://www.waze.com/forum/viewtopic.php?t=40705 forum] 🔗 || [https://greasyfork.org/en/scripts/3206-wme-color-highlights installation] 🔗
|-
|'''Magic''' || Highlighting Tool || [https://www.waze.com/forum/viewtopic.php?f=819&t=230927 forum] 🔗 || [https://waze.xpto.org/magic/magic.bundle.user.js installation] 🔗
|-
|'''Toolbox''' || Highlighting & Symbolizing Tool || [https://www.waze.com/forum/viewtopic.php?f=819&t=145570 forum] 🔗 || [https://chrome.google.com/webstore/detail/wme-toolbox/ihebciailciabdiknfomleeccodkdejn?hl=en installation] 🔗
|-
|'''Validator''' || Highlighting Tool || [https://www.waze.com/forum/viewtopic.php?t=76488 forum] 🔗 || [https://greasyfork.org/en/scripts/1571-wme-validator installation] 🔗
|}

Latest revision as of 17:30, 7 September 2021

Falcon Map Snapper is a mechanism in Waze that positions the car on the user's map in relation to the mapped roads by collecting data like GPS, accelerometer, GPS speed, and more. It was implemented in 2021 to replace an old mechanism called The Matcher, which was a simpler mechanism that only used GPS position in relation to the mapped roads.

Overview link to this section

What is The Matcher? link to this section

As you drive along your route, the arrow in the Waze app depicts your location on the Waze map. A technology, previously called the matcher, "snaps" the arrow to a segment on the map on your route. This association is very strongly bound to keep the arrow tied to the current route. As a result, Waze has often been slow to detect and recalculate changes when you deviate from the route, especially if the new route runs parallel to the old route.

Picture illustrating the concept of the Matcher and Snapper.
Illustrating the concept of the Matcher and Snapper.

What is Falcon Snapper? link to this section

The new Falcon Snapper is next generational and replaces The Matcher. It is smarter and more predictive than the previous matcher. It uses multiple sensors (including GPS) to determine the most likely position of the car in relation to the road. Its power setting is currently turned down though. Updates to our mapping standards have occurred, guiding editors in how to edit the Waze map to fully utilize the power of Falcon Snapper.

Falcon Snapper Mapping Principles link to this section

The community is leading the way in upgrading the Waze map to meet the new requirements of Falcon Snapper. We therefore need to change our thinking to these new principles:

  1. The map needs to be as accurate as possible and representative of reality: the position of the segment on the road, and the direction / angle of intersecting segments. Segments that do not meet these new principles could make Falcon hiccup, switch the arrow to another segment/route, and cause a poor user experience.
  2. We are moving away from using the map as a way to control the app. A map should be a map; it should be accurate and represent the world. The only time the map should deviate from reality is when an app function would be broken as a result of accurately drawing the map.

Mapping Guidance for Falcon Snapper link to this section

What are the primary goals for optimizing the map for Falcon Snapper?

Realign Segments link to this section

To enable Falcon to work as well as it can, segment positions need to be aligned with reality as closely as possible. To do this:

  1. Determine whether the satellite imagery in the area is trustworthy by comparing it with the GPS points layer.
  2. If the satellite imagery is trustworthy, align the segments to the center of the roadway using the satellite imagery.
  3. If the satellite imagery is not trustworthy, align the segments to the center of the tracks in the GPS points layer as closely as possible.

Determine Trustworthiness of Satellite Imagery link to this section

Determining the trustworthiness of satellite imagery is a very quick check you should do any time you’re adjusting roadway geometry. It takes only seconds (especially using the default shift-G and shift-R keyboard shortcuts to quickly switch on and off the GPS points and segments layers, respectively) and can save a ton of re-work.

First, enable the GPS points layer.

If the bulk of the arrows on the GPS points layer line up well with the roads on satellite imagery (even if there are some outliers), it is trustworthy, and you should use it as the basis for roadway alignment.

But if the arrows show a lot of traffic that is not aligned with roads visible in satellite imagery, you might have a problem.

Trustworthy Imagery link to this section

Screenshot illustrating trustworthy imagery against GPS trails.
In this image, the bulk of the arrows are well within the limits of the roadways, without any significant concentration of arrows showing a misalignment.
Screenshot illustrating trustworthy imagery against GPS trails.
This is another example of well-aligned imagery—even though there are “junk” arrows everywhere, there are strong concentrations of arrows that line up well with actual roads, so the imagery is trustworthy.

In cases where imagery is trustworthy, align segments with the satellite imagery.

Align the segments as close to the center of the road as practical.

  • On roads with multiple lanes, the lane lines can be used as a guide for finding the center of the road.
    • On one-way segments with an even number of lanes, the segment should cover the line between the middle two lanes.
    • On one-way segments with an odd number of lanes, the segment should run dead center in the middle lane.
  • Generally, follow the geometric center of the road.
    • On two-way segments, the geometric center will not always be the same as the roadway centerline that splits the two directions of traffic.
    • However, in cases where the geometric center of the roadway temporarily shifts near an intersection, don’t blindly “chase the turn lanes” if doing so would cause an abrupt correction at the intersection. Falcon Snapper is smart enough to know that roadways sometimes get wider near intersections. Keeping the path smooth is more important in these cases.

When the center of the road changes abruptly due to a change in the number of lanes, keep the transitions smooth.

Screenshot illustrating one-way segments on top of imagery.

One-way Segments Example 1 (Above Left) — Follow the geometric center of the roadway. On the 4-lane segments, the lane markings between the 2 middle lanes are a great reference.

Screenshot illustrating one-way segments on top of imagery.

One-way Segments Example 2

  • Westbound, a transition from 3 lanes to 2 lanes & 1 lane—note the transition is smooth. For the 3-lane portion, follow the center of the middle lane. For the 2-lane portion, follow the lane markings between the two lanes.
  • Eastbound upper, an easy 2 lanes, so follow the lane markings.
  • Eastbound lower, a smooth transition from 1 lane & 1 lane into 2 lanes, then an exit on the right while the 2 lanes continue onward. For the 1-lane portions, follow the center of the roadway. For the 2-lane portion, follow the lane markings between the two lanes.


Screenshot illustrating the difference between chasing turn lanes (not recommended) and not chasing turn lanes (preferred). Screenshot illustrating the difference between roads not mapped to the centerline, and roads mapped to the centerline.

Don’t “Chase the Turn Lanes” — Falcon is smart enough to know that roadways sometimes get wider near a turn. “Chasing the turn lanes” leads to awkward geometry at the junction itself, which is a bigger problem.

It’s okay to realign segments even if they are only off by a few feet or half a lane. We want our segments to be as close to reality as possible so that Falcon can work as well as possible.

Non-Trustworthy Imagery link to this section

Imagery is not trustworthy if it is either misaligned or out of date.

Screenshot illustrating how the GPS trails indicate that the imagery is not trustworthy. Screenshot illustrating how the GPS trails indicate that the imagery is not trustworthy.

In the first image, you can see a strong concentration of GPS tracks cutting through what appears to be forests and fields in satellite imagery. This strongly suggests that the roadway alignment has changed, so this imagery is not trustworthy.

In the second image, you can see a strong concentration of arrows that do not line up with the roadways visible on satellite imagery, but which have the same shape as the roadways.

If the imagery is not trustworthy, segments should be aligned with GPS tracks.

On a two-way road, you should see arrows of 2 different colors, showing 2 different directions of travel. Align the segment to the center of the two directions of travel:

On a one-way road, you should see a cluster of arrows of the same color. Align the segment with the center of this cluster.

Bridges and Overpasses link to this section

Even in areas with otherwise-trustworthy imagery, high-rise bridges and overpasses may be significantly misaligned. This is due to a phenomenon known as parallax. Because the satellite’s camera is not always directly above the places it’s photographing, anything not at ground level might not be aligned properly with things around it—while the satellite imagery provider does typically attempt to compensate for parallax error, it is not always successful. Where this error occurs, use satellite imagery to align segments at ground level, but follow the GPS tracks more closely as you near the peak of the bridge or overpass.

Screenshot illustrating how GPS trails indicate parallax in satellite imagery on elevated roadways.

Though most of the GPS tracks in this image show that the imagery is trustworthy—even on most of the elevated ramps and freeways in this image, upwards of 100 feet above ground level—the selected reversible HOV lane segments are misaligned by a bit. While the satellite imagery provider does attempt to correct parallax errors, it’s not perfect (and the blurriness of the imagery on those elevated roadways is further evidence of this).

Screenshot illustrating how GPS trails indicate parallax in satellite imagery on elevated roadways.

At the other end of the bridge, parallax error is quite evident on the elevated bridge approach segments, while the ground-level imagery is clearly trustworthy. Use the imagery at ground level; use the GPS tracks to align the bridge segments only.

Remove Fictional Doglegs and Micro-Doglegs link to this section

For years, doglegs and micro-doglegs have been used for several reasons: to force turn instructions (before turn instruction overrides were introduced), to force lane arrows (before lane arrow overrides were introduced), to make junction locations stand out on the map (before the on-route turn arrow overlay was introduced), and so on. All of these reasons have two things in common:

  1. they are no longer valid, as the map editor and app limitations that necessitated them have been addressed with native features, and
  2. they can cause problems with Falcon Snapper, which is sensitive to the angle of the driver’s movements.

Remember - The map needs to be as accurate as possible and representative of reality: the position of the segment on the road, and the direction and angle of intersecting segments.

Where found, micro-doglegs should be removed, and the segments mapped with the above guiding principles, to follow more closely with reality. Add Turn Instruction Overrides (TIOs) and Lane Angle Overrides (LAOs) where necessary to provide the best driver experience.

Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway. Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.

Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway. Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.

Screenshot illustrating a type of dogleg to avoid when mapping departures from the roadway. Screenshot illustrating a standard alternative to a dogleg when mapping departures from the roadway.

Exit, Fork, Split, Wayfinder, and AGC Geometry link to this section

Where two roads separate from each other as in an exit, fork, split, wayfinder, or AGC, there is one guiding question: is there a clear straight-ahead path? That is, does one outbound segment clearly continue the same path as the inbound segment?

 Screenshot illustrating a fork on a ramp where there is no clear straight-ahead path. Screenshot illustrating an exit ramp where there is a clear straight-ahead path on the main roadway. Screenshot illustrating an exit ramp where there is a clear straight-ahead path on the main roadway.

  • Left: no, there is no clear straight-ahead path.
  • Center: yes, the I-610 E outbound path is the clear straight-ahead path—even though both paths run parallel (at first), I-610 E is the actual continuation and has more lanes.
  • Right: yes, the left path is the clear straight-ahead path—even though these are exit ramps and there is no “continuation” per se, the left path is totally straight while the right path diverges immediately.

Where there is a clear straight-ahead path,

  • The straight-ahead path should be more or less straight, with a smooth transition.
  • The diverging path should be edited as follows:
    • First, place the first geometry handle of the diverging segment
      • on freeway exits and other ramps, at the nearest point to the exit from the following:
        • If there's no solid white line, at the gore point (or “theoretical gore”, i.e., where the painted lines begin to diverge);
        • If there's a solid white line, at its beginning;
        • On a multi-lane exit, at the gore point or (if present) solid white line between the inner exit lane and the main lanes of traffic;
          Screenshot illustrating the gore point of a multi-lane exit ramp.
        • 1/4 mile before the gore point, on exits with a longer solid white line; or
        • Halfway between the gore points of the exit and the previous exit.
      • on at-grade connectors, at the gore point (or “theoretical gore”).
    • Next, grab the node itself, where the segments meet, and adjust the geometry of the exit itself as follows:
      • If the actual path of the exit diverges from the inbound path by less than 20°, adjust the node to create a 20° departure angle. This will allow for consistent timing of exit instructions and make it easier to report closures in the Waze client.
      • If the actual path of the exit diverges immediately from the inbound path by more than 20°, adjust the node such that the exit path follows its true natural departure angle.
    • Ensure that the last geometry handle before the node is at least 40 feet ahead of the node, and that the second geometry handle on the diverging path is at least 40 feet beyond the first geometry handle.

Where there is not a clear straight-ahead path,

  • Adjust the inbound segment geometry to follow the true path of the inbound segment,
  • Set the first geometry handles of both outbound segments at the gore point, then
  • Grab the node and adjust such that the angle between the outbound segments is at least 15°.
    • If following the true natural departure angles leads to an inner angle of 15° or more, do that.
    • If the outbound segments are both equally straight ahead, ensure that the outbound paths at the node are essentially symmetrical.

 Screenshot illustrating how to set up outbound segments when there is a symmetrical departure of two ramps from an inbound segment. Screenshot illustrating how to set up outbound segments when there is a symmetrical departure of two ramps from an inbound segment.

  • Essentially symmetrical: yes, departure angles of outbound segments are very close (7° and 8°).
  • At least 15°: yes (de-select any segments and select the node to check).

At the other end, ramps and AGCs should enter the flow of traffic smoothly and naturally. Place the final geometry handle of a ramp or AGC at the gore point as shown below, then grab the node and pull it along the road to create a smooth, natural entry angle:

Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway.

Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway. Screenshot illustrating how to set up the gore point for a re-entry ramp onto a main highway.

Smooth re-entry. Just like the Apollo guys did back in the day.

Dividing Roads link to this section

As a “rule of thumb” - when there is a physical divider between the road (e.g. a small wall, grass, trees) and you cannot cross in a typical car, then map it with parallel one-way segments to more accurately represent reality.

Screenshot illustrating a road with a physical divider that would need to be divided on the map.
Screenshot illustrating a road with a physical divider that would need to be divided on the map.

When To Divide a Road link to this section

A road should be divided when any of the following conditions are met:

  • It is an Interstate Highway, other freeway, or other controlled- or limited-access road with separated directions of travel, or
  • There is a physical median or other traffic control device which makes it impossible or illegal to turn left onto or off of the road, including but not limited to where
  • Houses, businesses, or other destinations are located directly on the street but are not accessible from the opposite direction of travel due to a median or other traffic control device that either physically or legally prohibits such access, or
  • U-turns are required for proper navigation to or from side roads or destinations.

When Not To Divide a Road link to this section

A road should not be divided when any of the following conditions is met:

  • There is a shared two-way center turn lane (of any width) between the directions of travel, or
  • It is both possible and legal to make a left turn across the roadway centerline at any point along the road (e.g., across a normal double yellow line to enter a driveway).

This is expected to create a lot more H and # (hash) junctions. Where they’re complex, junction boxes may be required. See junction boxes below.

You must consider U-turn prevention and take measures to allow or disallow U-turns where possible or impossible. To prepare for turning off the old U-turn prevention, junction boxes should be used instead of prior guidance that will be deprecated.

Junction Boxes link to this section

With the creation of a lot more potentially complex junctions and accurately matching roads to reality, there may be a need to add junction boxes to the intersections, or sets of intersections, you’re creating.

A junction box should be used when necessary to:

  • Prohibit an illegal or impossible path that cannot be prohibited with a simple turn restriction;
  • Prevent illegal U-turns at H and # intersections;
  • Enable collection of differential traffic data at # and H intersections (i.e., enable the routing server to tell the difference between left turn and straight-through delays);
  • Enable collection of differential traffic data where traffic backs up past junction nodes before the intersection (e.g., because of another intersection, at-grade connector (AGC), exit ramp, or parking lot road) where the backup timing is expected to be different depending on which way the driver eventually exits the intersection; or
  • To better collect traffic data on intricate intersections.

If a junction box is needed, make sure it is the last thing that needs to be done. Once added, the JB needs to be deleted for certain modifications to the segments and nodes beneath it (most notably, nodes under a JB cannot be moved, and segments connected to a JB cannot be cut).

In the United States, Level 4 and above can add/modify junction boxes. If you add one, please note on the Map Raid sheet. If you think one is needed, but you’re unable to add it, please note on the Map Raid sheet.

Mapping of Dedicated Turn Lanes / AGCs link to this section

Do dedicated turn lanes and at-grade connectors (AGCs) need mapping? In exceptional cases only.

In the below example, note the points A and B. Falcon Snapper has a feature called “curver” which expects drivers to turn in a curve between these two points. Curver stops at geometry handles, so be sure to minimize them close to intersections. Also note that the islands created by the AGCs are small and do not result in much of a delay in the final turn instruction.

Screenshot illustrating islands at an intersection for discussion of the Falcon Snapper's curver feature.

An AGC is indicated if it:

  1. Red arrow: creates a large island, where, without the AGC the late turn instruction will result in the driver missing the turn.
  2. Green arrow: geo nodes are required close to the actual turn to shape the road to match reality that affect the Falcon Snapper curver ability.
  3. The AGC contains essential wayfinder information.

Screenshot illustrating an AGC with a large island and curvature of a main road close to the junction. Screenshot illustrating a large island at an intersection which would require mapping of an AGC.