User:Ojlaw/Junction Style Guide/Intersections View history

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=== Right angles ===
=== Right angles ===
{| class="Wikitable floatright"
[[File:3way90.png|200px|frameless|right]]
| [[Image:Jct_3_90_ex.png|border]]
| [[Image:Jct_3_90.png|border|x199px]]
|}
The simplest junctions often resemble a "T" and are considered diverging or branch roads. The branch road will normally meet the main road at nearly a 90 degree angle. This is the simplest situation to map, as the physical and logical views of the roads match up well.
The simplest junctions often resemble a "T" and are considered diverging or branch roads. The branch road will normally meet the main road at nearly a 90 degree angle. This is the simplest situation to map, as the physical and logical views of the roads match up well.
{{clear}}
{{clear}}


=== Odd angles ===
=== Skewed angles ===
{| class="Wikitable floatright"
[[File:3wayskewed.png|200px|frameless|right]]
| [[Image:Jct_3_45_ex1.png|border]]
Some roads meet at skewed angles. These intersections should be mapped to reality. Mapping these to reality can result in turn instructions that would not match what the driver expects. Thus, at these intersections it is important to check the geometry, road types, and names to understand what instructions are given. If the default instruction is not desirable then a [[Voice_prompt|voice prompt]] override should be used.
| [[Image:Jct_3_45.png|border|x200px]]
 
|}
* Depending on the angle, the client may give a "keep right or keep left" instruction to the driver when a "turn right or turn left" instruction is more appropriate. If Minor Highways or above are involved, you will actually get an "''Exit'' Right" which can be confusing in many situations.
Some roads meet at odd angles. The initial urge will be to represent the junction as it is in the physical world - two lines running into each other at a sharp angle. But there are issues with this method.
* In some cases, no instruction will be given at all.  
* Depending on the angle, the client may give a "Keep Right" instruction to the driver when a "Turn Right" instruction is more appropriate. If Minor Highways or above are involved, you will actually get an "''Exit'' Right" which can be confusing in many situations.
The [[Junction_Style_Guide/Controlling_turn_instructions|controlling turn instructions]] article has more information on the specifics of geometry, road types and names and how they affect turn instructions.  
* In some cases, no instruction will be given at all. In the worst case, the [[routing server]] may determine that it isn't possible to make a very sharp turn angle and not suggest the turn at all (in the example image, heading south, then turning left, to head east).
* Automatic map errors may appear with turns from one direction as the path of the turning traffic is "too far" away from the actual junction (in this example, traveling south, then turning left to head east).
{{clear}}
{{clear}}


====Doglegs====
{| class="Wikitable floatright"
{| class="Wikitable floatright"
| [[Image:Jct_3_45_curve.png|border]]
| [[Image:3waydogleg12m.png|border|x200px]]
| [[Image:3waydogleg12m-2.png|border|x200px]]
|}
|}
To eliminate ambiguity, map the junction from a logical point of view. Since basic "Turn Left" and "Turn Right" instructions are desired, tweak the intersecting angle so it resembles a basic 90 degree intersection. Add [[Glossary#Geometry node|geometry nodes]] to make the branch road leave the main road at close to 90 degrees, then gradually curve the road to match the true departure angle. This will produce a junction that logically works like a basic 90 degree junction, but it also fits the reality of the physical world.
Doglegs can be added to better represent reality or aid in turn instruction timing where the large area of pavement should consider turns from all directions. When doglegs are added the first [[geometry node|geometry handle]] should be placed a minimum of 12m (40ft) from the intersection node when measured with the [[Map_Editor_Interface_and_Controls#Ruler|ruler]].
{{clear}}
{{clear}}
A deprecated method to control instructions at these intersections involved adding micro-doglegs (geometry handles placed very close to the node) to create geometry that would give the desired turn instruction. These intersections should be updated, micro-doglegs should be removed, and [[Voice_prompt|voice prompt]] overrides should be added if necessary.


{| class="Wikitable floatleft"
===Name changes on continuing path===
| [[Image:Jct_3_45_ex.png|200px|border]]
For conditions where the through route changes road names, it is important to identify which segment is drawn as the continuing route and which is shown as the deviation from the main road. As the [[How_Waze_determines_turn_/_keep_/_exit_maneuvers|How Waze Determines turn/keep/exit maneuvers]] page explains, segment names and geometry are very important in determining what navigation instructions are given. Map these intersections according to the principles in this article and use voice prompt overrides as necessary for the proper turn instructions.
|}
Here is a completed real world example which provides the expected turn instructions and "catches" turns from all directions avoiding automatic problems for [[Map_Problems_in_Waze_Map_Editor#Missing_road|missing road]] when they are "too far apart."
{{clear}}
 
=== Name changes on straight path ===
For conditions where the straight through route changes road names, it is important to identify which segment is drawn as the straight route and which is shown as the right turn from the main road. As the [[How_Waze_determines_turn_/_keep_/_exit_maneuvers|How Waze Determines turn/keep/exit maneuvers]] page explains, segment names and geometry are very important in determining what navigation instructions are given.


{{Anchor|Name changes on continuing path}}
{{Collapsible section top}}
{{HighlightBar|'''Name changes on continuing path example'''}}
Just click on the expand link to the right ------>
{{Collapsible section content}}
{{NeedInfo|'''The following section needs work and an example where the roads are mapped correctly and VPOs are used. These images are not correct and it's currently not mapped correctly in WME.'''
[[Image:Jct_Y_ex_aerial.png|200px|right|border]]
[[Image:Jct_Y_ex_aerial.png|200px|right|border]]
In this example to the right, the multi-lane surface street is known as Main Street to the west and Atlantic Ave. to the east. The name change occurs when Main St. branches off as a regular surface street. That is the human description, but a more technical description would be that Main St. travels in a perfectly straight line and Atlantic Ave. branches off of it. But if we map it that way in the editor, we create a major problem.
In this example to the right, the multi-lane surface street is known as Main Street to the west and Atlantic Ave. to the east. The name change occurs when Main St branches off as a local street from the highway. That is the human description, but a more technical description would be that Main St travels in a perfectly straight line and Atlantic Ave branches off of it. But if we map it that way in the editor, we create a major problem.
{{clear}}
{{clear}}


[[Image:Jct_Y_ex_map_bad.png|200px|left|border]]
[[Image:Jct_Y_ex_map_bad.png|200px|left|border]]
Since the multi-lane segment of Main St. and the regular street segment of Main St. have the same name, the routing engine automatically considers that to be "straight". If the two sections line up in a straight line the way they appear from the sky, then we are reinforcing the idea that "straight" is Main St. to Main St. But as a typical driver would want, "straight" should be the path that remains on the multi-lane roadway, regardless of what name it uses.
Since the multi-lane segment of Main St and the regular street segment of Main St have the same name, the routing engine automatically considers that to be the continuation of the highway. If the two sections line up in a straight line the way they appear from the sky, then we are reinforcing the idea that "continuation" is Main St to Main St But as a typical driver would want, "continuation" should be the path that remains on the multi-lane highway, regardless of what name it uses.
{{clear}}
{{clear}}


[[Image:Jct_Y_ex_map.png|200px|right|border]]
[[Image:Jct_Y_ex_map.png|200px|right|border]]
To make sure the routing engine understands the proper treatment of the junction, we have to be deliberate with the segment geometry of all three involved segments.  We end up with something like the image on the right. Now the geometric definition of straight is the multi-lane portion of Main St. onto Atlantic Ave., since we have made that transition as close to zero degrees as possible. The regular street portion of Main St. now branches off at an angle close to 90 degrees. The routing engine should recognize that a turn is required. So the result is that Main St. to Atlantic Ave. has no announced turn, and multi-lane Main St. to surface road Main St. has a turn announced. Exactly what most drivers would expect in the real world.
To make sure the routing engine understands the proper treatment of the junction, we have to be deliberate with the segment geometry of all three involved segments.  We end up with something like the image on the right. Now the geometric definition of straight is the multi-lane portion of Main St. onto Atlantic Ave., since we have made that transition as close to zero degrees as possible. The regular street portion of Main St. now branches off at an angle close to 90 degrees. The routing engine should recognize that a turn is required. So the result is that Main St. to Atlantic Ave. has no announced turn, and multi-lane Main St. to surface road Main St. has a turn announced. Exactly what most drivers would expect in the real world.
}}
{{Collapsible section bottom}}


=== Steep angles with exits and keep right or left ===
=== Steep angles with exits and keep right or left ===
{|
The straight ahead path should be more or less straight, with a smooth transition.
|-
| [[File:Jct ramp no geo.png|border|Jct ramp no geo.png]]
| [[File:Jct ramp no geo arrow.png|border|Jct ramp no geo arrow.png]]
|}


A ramp from a highway is another good example where additional geometry nodes are helpful. Especially since most ramps diverge at a very small angle from the road. The drawback in this case is it may be hard to see and click on the turn restriction arrows in the editor.
The diverging path should be configured as follows:


{|
*First, place the first [[geometry node|geometry handle]] of the diverging segment at the gore point (or "theoretical gore", i.e., where the painted lines diverge).
|-
[[File:Steep angles.png|200px|frameless|right]]
| [[File:Jct ramp w geo.png|border|Jct ramp w geo.png]]
*Next, grab the node itself, where the segments meet, and adjust the geometry of the diverging path as follows:
| [[File:Jct ramp w geo arrow.png|border|Jct ramp w geo arrow.png]]
**If the actual path 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 instructions and make it easier to report closures in the Waze client.
|}
**If the actual path of the road diverges immediately from the inbound path by more than 20°, adjust the node such that the road path follows its true natural departure angle.
*Next, 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.
*Finally, check the turn instructions for both paths according to [[Junction_Style_Guide/Controlling_turn_instructions|controlling turn instructions]] and if necessary add [[Voice_prompt|voice prompt]] overrides for the desired instruction.


Therefore, add one more geometry node to make the departure angle at the junction closer to 10 or 20 degrees. (dogleg) See the discussion on [[Junction Style Guide#Controlling Turn Instructions|controlling turn instructions]] for details on those angles. Now the arrows are visible and accessible. Note that also pressing '''s''' in the editor will '''s'''pread or '''s'''eparate the arrows at a junction, if an arrow is still difficult to reach. See the [[Keyboard shortcut|keyboard shortcuts]] article for more tips on other keys.
{{clear}}
 
With this adjusted angle, this junction now behaves as expected and the turn restrictions can be easily accessed. {{clear}}


== Four-way ==
== Four-way ==


=== Right angles ===
=== Right angles ===
{| class="Wikitable floatright"
[[File:4way90.png|200px|frameless|right]]
| [[Image:Jct_4_90_ex.png|border]]
The second simplest junction category is a "+" or "cross" four-way junction that intersects at 90 degrees. These roads are simple to map as the logical and physical views of the roads match up well.  
| [[Image:Jct_4_90.png|border|x200px]]
|}
The second simplest junction category is a "+" or "cross" four-way junction that intersects at 90 degrees. These roads are simple to map as the logical and physical views of the roads match up well. These instructions follow the similar guidelines and solve the same problems as [[Junction Style Guide/Diverging roads|diverging roads]].
{{clear}}
{{clear}}


=== Odd angles ===
=== Skewed angles ===
{| class="Wikitable floatright"
[[File:4way90skewed.png|200px|frameless|right]]
| [[Image:Jct_4_45_ex1.png|border]]
Similar to diverging roads that intersect at skewed angles, crossing roads can do the same thing. These intersections should be mapped to reality. Mapping these to reality can result in turn instructions that would not match what the driver expects. Thus, at these intersections it is important to check the geometry, road types, and names to understand what instructions are given. If the default instruction is not desirable then a [[Voice_prompt|voice prompt]] override should be used.
| [[Image:Jct_4_45.png|border|x200px]]
|}
Similar to diverging roads that intersect at odd angles, crossing roads can do the same thing. When these intersections are mapped as seen here with these odd angles, complications can occur.
{{clear}}


{| class="Wikitable floatright"
* Depending on the angle, the client may give a "keep right or keep left" instruction to the driver when a "turn right or turn left" instruction is more appropriate. If Minor Highways or above are involved, you will actually get an "''Exit'' Right" which can be confusing in many situations.
| [[Image:Jct_4_45_curve.png|border|x200px]]
* In some cases, no instruction will be given at all.  
|}
The [[Junction_Style_Guide/Controlling_turn_instructions|controlling turn instructions]] article has more information on the specifics of geometry, road types and names and how they affect turn instructions.  
[[Glossary#Geometry_node|Geometry nodes]] bring the actual junction close to 90 degrees. [[Map_Editor_Interface_and_Controls#Zoom_Control|Zoom]] in to the intersection and add a single geometry node on each side as close to the junction point as possible. This will give the more desirable 90 degree angle, and it will still be virtually invisible to client app users making it look like the physical world. This image is what is seen when zoomed in as close as possible. Zoomed back out, it looks just like the map image showing the junction without any geometry nodes.
{{clear}}
{{clear}}


{| class="Wikitable floatleft"
A deprecated method to control instructions at these intersections involved adding micro-doglegs (geometry handles placed very close to the node) to create geometry that would give the desired turn instruction. These intersections should be updated, micro-doglegs should be removed, and [[Voice_prompt|voice prompt]] overrides should be added if necessary.
| [[Image:Jct_4_45_ex.png|border]]
|}
Here is a real world example at a close zoom level where you can still see the geometry adjustment. With that adjustment in place, the junction will produce predictable turn left and right navigation instructions while the roads still appear to meet at the real-world angle in the client app.
{{clear}}


== {{anchor|Split road intersections}}Divided road intersections==
== {{anchor|Split road intersections}}Divided road intersections==
Many of the principles stated above apply to intersections between divided roads. Usually, divided road intersections should look like the traffic lanes they represent. "Box" shaped intersections are easiest to draw, maintain, and to explain to other editors.  Only use variations when they are needed.
Many of the principles stated above apply to intersections between divided roads. Usually, divided road intersections should look like the traffic lanes they represent. "Box" shaped intersections are easiest to draw, maintain, and to explain to other editors.  Only use variations when they are needed.
Read through the pros and cons of the intersection types below and select the best suited.
{{NeedInfo|Insert examples of a divided road intersecting a two-way road, two divided roads intersecting each other, 3-way intersections involving divided roads, intersections where one road changes between  divided/2-way at the intersection...}}


=== Box and partial box intersections ===
=== Box and partial box intersections ===
Box and partial box intersections are also referred to as # and H intersections in the Waze editor community.  These intersections should be mapped as close to reality as possible. The below style guide addresses some unique circumstances.


This type of intersection is most useful in intersections where the traffic queues in a median segment that is long enough to justify being mapped, especially if the one-way roads would have to deviate greatly from their physical location to meet in a single point for a bow tie. This also allows the map to route correctly while representing the actual geometry of the roads in real life, which is more intuitive to users.
When creating three way and four way intersections, if the cross street changes names at the junction, make sure that the median segment(s) have no name. This will cause the segment to inherit the appropriate name depending on the direction of travel.  The median segment will not be included when you choose "Select entire street". Conversely, leave the median segment(s) named if the street maintains name continuity through the intersection.
 
Do not use this type of junction if the crossbar will be less than {{:Segment length/Minimum}}. Waze has difficulty in capturing average speeds for short segments, especially in wide intersections where traffic travels a fairly curved path rather than sticking close to the segment.  Add in the inaccuracy of many phone GPS units, and you may have a situation where the reported positions of some of the vehicles are never on the segment during the maneuver.
 
When creating three way and four way intersections, if the cross street changes names at the junction, make sure that the segment(s) have no name. This will cause the segment to inherit the appropriate name depending on the direction of travel.  This center segment will not be included when you choose "Select entire street".
 
Three way divided road intersections are easier to edit accurately than four way intersections.
 
{{NeedInfo|Insert examples: divided road ends at 2-way road (single point if both lefts are allowed and u turns are not); divided road ends at divided road ("triangle" in median if both lefts are allowed and u turns are not); 2-way road ends at divided road (easy).}}
 
[[Image:3wayunsplitsplit.png]]
 
If possible, lay out the intersection to resemble reality.  When all divided-road U turns are allowed at an intersection, or when disallowed U turns are effectively restricted in Waze by existing restricted left turns already, use the guidance in this section.
 
When a U turn must be restricted, but both of the left turns that make up that U turn are allowed on their own, follow the guidance in [[#Avoiding U turns|Avoiding U turns]] below.
 
{{NeedInfo|Insert examples: divided road intersects a 2-way road (≠); two divided roads intersect (#); intersection where one road changes between divided/2-way at the intersection...}}


{| class="wikitable"
{| class="wikitable"
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! Intersection style !! Example
! Intersection style !! Example
|-
|-
| A divided road intersecting a divided road. || [[Image:4waysplitsplit.png|300px]]
| A divided road intersecting a divided road. https://waze.com/en-US/editor?env=usa&lat=34.20627&lon=-119.14201&s=1343600087&zoomLevel=19 || [[Image:Divided road intersecting a divided road.png|300px]]
|-
| A divided road intersecting a 2-way road. https://waze.com/en-US/editor?env=usa&lat=34.20620&lon=-119.15132&s=1343600087&zoomLevel=20 || [[Image:Divided road intersecting a 2-way road.png|300px]]
|-
| A transitioning (divided-2-way) road intersecting a 2-way road. https://waze.com/en-US/editor?env=usa&lat=34.25435&lon=-119.19747&s=1343600087&zoomLevel=18 || [[Image:Transitioning (divided-2-way) road intersecting a 2-way road.png|300px]]
|-
| A transitioning (divided-2-way) road intersecting a divided road. || [[Image:Transitioning (divided-2-way) road intersecting a divided road.png|300px]]
|-
| A transitioning (divided-2-way) road intersecting a transitioning (divided-2-way) || [[Image:Transitioning (divided-2-way) road intersecting a transitioning (divided-2-way).png|300px]]
|-
| A divided road T at a 2-way road. || [[Image:Divided road T at a 2-way road.png|300px]]
|-
|-
| A divided road intersecting a 2-way road. || [[Image:4waysplitunsplit.png|300px]]
| A divided road T at a divided road. || [[Image:Divided road T at a divided road.png|300px]]
|-
|-
| A transitioning (divided-2-way) road intersecting a 2-way road. || [[Image:Split_road_to_sinlge_road.png|300px]]
| A divided road T at a 2-way road transitioning to a divided road. || [[Image:A divided road T at a 2-way road transitioning to a divided road.png|300px]]
|-
|-
| A transitioning (divided-2-way) road intersecting a divided road. || (image)
| A 2-way road T at a 2-way road transitioning to a divided road. || [[Image:2-way road T at a 2-way road transitioning to a divided road.png|300px]]
|-
|-
| Be careful with your geometry – following the center of the actual road too closely can lead to rather high turn angles, and therefore possibly unwanted turn instructions. Keep it smooth. || [[Image:Transition.png|300px]]
| Be careful with your geometry – following the center of the actual road too closely can lead to rather high turn angles, and therefore possibly unwanted turn instructions. Keep it smooth. Departure angles on the transitioning segments should be less than 15°. || [[Image:Be careful with your geometry.png|300px]]
|}
|}


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{{Anchor|Bowtie}}
{{Anchor|Bowtie}}


[[File:Jct_bowtie.png|301px|thumbnail|right|The bow tie intersection is NOT RECOMMENDED]]The bow tie intersection is no longer the best way to take control of turns and traffic at divided-road intersections. It is an unrealistic representation of an intersection and drivers report map errors based on this appearance. It was necessary before the introduction of the [[junction box]] and the 3-segment U-turn prevention mechanism, but now there are better methods to control turns and properly account for queuing.
[[File:Jct_bowtie.png|301px|thumbnail|right|The bow tie intersection is NOT RECOMMENDED]]The bow tie intersection is no longer the best way to take control of turns and traffic at divided-road intersections. It is an unrealistic representation of an intersection and drivers report map errors based on this appearance. It was necessary for controlling turns and accurately reflecting traffic queuing before the introduction of the [[junction box]], but now there are better methods to control turns and properly account for queuing.


* Where Waze seems to be doing a poor job of keeping track of traffic queuing, a junction box is recommended.
* Where Waze seems to be doing a poor job of keeping track of traffic queuing, a junction box is recommended.
* To prevent U-turns at box or partial box intersections use a junction box
* To prevent U-turns at intersections use a junction box.
* In complicated situations, control u-turns prompts using a junction box.
* Do not add new bow ties to the map.
* Do not add new bow ties to the map.
* When you find a bow tie intersection on the map, check if it can be replaced by a realistically drawn intersection using other techniques to control turns and traffic.
* When you find a bow tie intersection on the map, check if it can be replaced by a realistically drawn intersection using other techniques to control turns and traffic.
* If you think it is necessary to add a bow tie to the map, contact state managers to discuss the intersection. They will most likely recommend a better approach.
* If you think it is necessary to add a bow tie to the map, contact state managers to discuss the intersection. They will most likely recommend a better approach.
* A bowtie intersection may be necessary at 5-point or greater intersections where a junction box cannot be used because of too many connections


=== Avoiding U-turns in box and partial box intersections ===
=== U-turn prevention in box and partial box intersections ===
{{As of|2021|12|df=US}} the Waze routing algorithm [[Routing penalties#Road_configurations|penalizing]] some double-left and double-right turns '''has been disabled in the United States'''. The routing server will no longer automatically avoid double-left turns. '''To prevent u-turns on divided roads, use a [[Junction box]].'''
{{:Editing Routing penalties/Controlling U-turn penalties/Disabled}}
==== Historic U-turn routing prevention ====
You may encounter intersections that appear pinched with a median segment that is shorter than reality. This was likely mapped prior to December 2021 to prevent u-turns. The intersection should be updated to match reality and a junction box used to prevent u-turns if necessary.
The Waze routing algorithm previously had a method of penalizing some double-left and double-right turns. This used to prevent U-turns at H or # style intersections on divided and parallel roads. [[Routing_penalties/Controlling_U-turn_penalties#Historic_U-turn_routing_prevention|Here]] is information on how this used to work.
  {{clear}}
  {{clear}}
{{ReturnTo | Junction_Style_Guide | the Junction Style Guide}}
{{ReturnTo | Junction_Style_Guide | the Junction Style Guide}}
[[Category:Style Guide]]
[[Category:Style guides]]

Latest revision as of 02:39, 2 November 2022

Three-way

Right angles

The simplest junctions often resemble a "T" and are considered diverging or branch roads. The branch road will normally meet the main road at nearly a 90 degree angle. This is the simplest situation to map, as the physical and logical views of the roads match up well.

Skewed angles

Some roads meet at skewed angles. These intersections should be mapped to reality. Mapping these to reality can result in turn instructions that would not match what the driver expects. Thus, at these intersections it is important to check the geometry, road types, and names to understand what instructions are given. If the default instruction is not desirable then a voice prompt override should be used.

  • Depending on the angle, the client may give a "keep right or keep left" instruction to the driver when a "turn right or turn left" instruction is more appropriate. If Minor Highways or above are involved, you will actually get an "Exit Right" which can be confusing in many situations.
  • In some cases, no instruction will be given at all.

The controlling turn instructions article has more information on the specifics of geometry, road types and names and how they affect turn instructions.

Doglegs

Doglegs can be added to better represent reality or aid in turn instruction timing where the large area of pavement should consider turns from all directions. When doglegs are added the first geometry handle should be placed a minimum of 12m (40ft) from the intersection node when measured with the ruler.

A deprecated method to control instructions at these intersections involved adding micro-doglegs (geometry handles placed very close to the node) to create geometry that would give the desired turn instruction. These intersections should be updated, micro-doglegs should be removed, and voice prompt overrides should be added if necessary.

Name changes on continuing path

For conditions where the through route changes road names, it is important to identify which segment is drawn as the continuing route and which is shown as the deviation from the main road. As the How Waze Determines turn/keep/exit maneuvers page explains, segment names and geometry are very important in determining what navigation instructions are given. Map these intersections according to the principles in this article and use voice prompt overrides as necessary for the proper turn instructions.

 Name changes on continuing path example  Just click on the expand link to the right ------>

The following section needs work and an example where the roads are mapped correctly and VPOs are used. These images are not correct and it's currently not mapped correctly in WME.

In this example to the right, the multi-lane surface street is known as Main Street to the west and Atlantic Ave. to the east. The name change occurs when Main St branches off as a local street from the highway. That is the human description, but a more technical description would be that Main St travels in a perfectly straight line and Atlantic Ave branches off of it. But if we map it that way in the editor, we create a major problem.

Since the multi-lane segment of Main St and the regular street segment of Main St have the same name, the routing engine automatically considers that to be the continuation of the highway. If the two sections line up in a straight line the way they appear from the sky, then we are reinforcing the idea that "continuation" is Main St to Main St But as a typical driver would want, "continuation" should be the path that remains on the multi-lane highway, regardless of what name it uses.

To make sure the routing engine understands the proper treatment of the junction, we have to be deliberate with the segment geometry of all three involved segments. We end up with something like the image on the right. Now the geometric definition of straight is the multi-lane portion of Main St. onto Atlantic Ave., since we have made that transition as close to zero degrees as possible. The regular street portion of Main St. now branches off at an angle close to 90 degrees. The routing engine should recognize that a turn is required. So the result is that Main St. to Atlantic Ave. has no announced turn, and multi-lane Main St. to surface road Main St. has a turn announced. Exactly what most drivers would expect in the real world.

Steep angles with exits and keep right or left

The straight ahead path should be more or less straight, with a smooth transition.

The diverging path should be configured as follows:

  • First, place the first geometry handle of the diverging segment at the gore point (or "theoretical gore", i.e., where the painted lines diverge).
  • Next, grab the node itself, where the segments meet, and adjust the geometry of the diverging path as follows:
    • If the actual path 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 instructions and make it easier to report closures in the Waze client.
    • If the actual path of the road diverges immediately from the inbound path by more than 20°, adjust the node such that the road path follows its true natural departure angle.
  • Next, 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.
  • Finally, check the turn instructions for both paths according to controlling turn instructions and if necessary add voice prompt overrides for the desired instruction.

Four-way

Right angles

The second simplest junction category is a "+" or "cross" four-way junction that intersects at 90 degrees. These roads are simple to map as the logical and physical views of the roads match up well.

Skewed angles

Similar to diverging roads that intersect at skewed angles, crossing roads can do the same thing. These intersections should be mapped to reality. Mapping these to reality can result in turn instructions that would not match what the driver expects. Thus, at these intersections it is important to check the geometry, road types, and names to understand what instructions are given. If the default instruction is not desirable then a voice prompt override should be used.

  • Depending on the angle, the client may give a "keep right or keep left" instruction to the driver when a "turn right or turn left" instruction is more appropriate. If Minor Highways or above are involved, you will actually get an "Exit Right" which can be confusing in many situations.
  • In some cases, no instruction will be given at all.

The controlling turn instructions article has more information on the specifics of geometry, road types and names and how they affect turn instructions.

A deprecated method to control instructions at these intersections involved adding micro-doglegs (geometry handles placed very close to the node) to create geometry that would give the desired turn instruction. These intersections should be updated, micro-doglegs should be removed, and voice prompt overrides should be added if necessary.

Divided road intersections

Many of the principles stated above apply to intersections between divided roads. Usually, divided road intersections should look like the traffic lanes they represent. "Box" shaped intersections are easiest to draw, maintain, and to explain to other editors. Only use variations when they are needed.

Box and partial box intersections

Box and partial box intersections are also referred to as # and H intersections in the Waze editor community. These intersections should be mapped as close to reality as possible. The below style guide addresses some unique circumstances.

When creating three way and four way intersections, if the cross street changes names at the junction, make sure that the median segment(s) have no name. This will cause the segment to inherit the appropriate name depending on the direction of travel. The median segment will not be included when you choose "Select entire street". Conversely, leave the median segment(s) named if the street maintains name continuity through the intersection.

Intersection style Example
A divided road intersecting a divided road. https://waze.com/en-US/editor?env=usa&lat=34.20627&lon=-119.14201&s=1343600087&zoomLevel=19
A divided road intersecting a 2-way road. https://waze.com/en-US/editor?env=usa&lat=34.20620&lon=-119.15132&s=1343600087&zoomLevel=20
A transitioning (divided-2-way) road intersecting a 2-way road. https://waze.com/en-US/editor?env=usa&lat=34.25435&lon=-119.19747&s=1343600087&zoomLevel=18
A transitioning (divided-2-way) road intersecting a divided road.
A transitioning (divided-2-way) road intersecting a transitioning (divided-2-way)
A divided road T at a 2-way road.
A divided road T at a divided road.
A divided road T at a 2-way road transitioning to a divided road.
A 2-way road T at a 2-way road transitioning to a divided road.
Be careful with your geometry – following the center of the actual road too closely can lead to rather high turn angles, and therefore possibly unwanted turn instructions. Keep it smooth. Departure angles on the transitioning segments should be less than 15°.

Bow tie

The bow tie intersection is NOT RECOMMENDED

The bow tie intersection is no longer the best way to take control of turns and traffic at divided-road intersections. It is an unrealistic representation of an intersection and drivers report map errors based on this appearance. It was necessary for controlling turns and accurately reflecting traffic queuing before the introduction of the junction box, but now there are better methods to control turns and properly account for queuing.

  • Where Waze seems to be doing a poor job of keeping track of traffic queuing, a junction box is recommended.
  • To prevent U-turns at intersections use a junction box.
  • Do not add new bow ties to the map.
  • When you find a bow tie intersection on the map, check if it can be replaced by a realistically drawn intersection using other techniques to control turns and traffic.
  • If you think it is necessary to add a bow tie to the map, contact state managers to discuss the intersection. They will most likely recommend a better approach.
  • A bowtie intersection may be necessary at 5-point or greater intersections where a junction box cannot be used because of too many connections

U-turn prevention in box and partial box intersections

 As of December 2021, the Waze routing algorithm penalizing some double-left and double-right turns has been disabled in the United States. The routing server will no longer automatically avoid double-left turns. To prevent u-turns on divided roads, use a Junction box.

You may encounter intersections that appear pinched with a median segment that is shorter than reality. This was likely mapped prior to December 2021 to prevent u-turns. The intersection should be updated to match reality and a junction box used to prevent u-turns if necessary.

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