# Changes

## Junction Style Guide

, 4 months ago
m
{{NeedImage}}<!--Editorial Reminders--><!--To Do - Bow Tie intersections --><!--To Do - U-Turn Solutions for "Road not connected" error -->{{construction| contact = https://www.waze.com/forum/viewtopic.php?f=1636&t=283510| contacttype = forum| draft = no| open = no| revision = yes| talk = yes}}
The following article contains key information on properly creating junctions and the roadways between them. Be sure to review it in its entirety before editing the map.
== Simple is better ==
: == The basics ==This guide requires a complete understanding of editing the maps with [[Image:Jct_4_90_ex.pngWaze Map Editor]] [[Image:Jct_4_90(WME).png‎ ]]
And if we have that street cutting across town at an odd angle, we want === Map editing 101 ===Although it is highly recommended to avoid read the odd angle at [[editing manual]] before touching the map, it is required that you do not continue with this guide until you have read the junction.following:* [[Map Editing Quick-start Guide|Map Editing Quick-start Guide]]* [[Creating and editing road segments#Junctions|Moving and removing junctions]]
=== Junction definition ==={| class="Wikitable floatright"| [[Image: Junction_selected.png|50px|border]]| [[Image:Jct_4_45_ex1Uneditable_junction.png|50px|border]] | [[Image:Jct_4_45junction_unsaved.png|50px|border]]|}The [[Glossary#Junction or Junction Point|Glossary on Junctions]]provides details on how junctions can appear differently in the editor depending on its state or condition.
We want to use geometry nodes to bring the actual A junction close to 90 degrees. You can zoom in and add a single geometry node on each side. This will give the proper angle but make it virtually invisible to users so it looks just like the physical world.is made up of three things: : # Two or more road [[Image:Jct_4_45_curve.pngCreating and editing road segments|segments]] The above image is what you would see zoomed in as close as possible. Zoomed back out, it looks just like # One point where all the image showing segments meet (the [[junction without any geometry nodes.point]] itself) And here is a real world example at a zoom level where you can still see the geometry adjustment we added: : # [[Image:Jct_4_45_exMap Editing Quick-start Guide#Turn restrictions .28allowed turns.png29|Turns allowed or restricted]] With when traveling from one segment to another through that adjustment in place, the junction will produce predictable turn left/right navigation instructions while the roads still appear to meet at the real-world angle.point{{clear}}
== Controlling Turn Instructions ==
{| class="Wikitable floatright" cellpadding="5" border="1" style="text-align:center; border: 1px solid darkgray;"
|-
| Keep Right || Keep Left
|-
| Turn Right || Turn Left
|-
| Exit Right || Exit Left
|}
Turn instructions are critical for proper client navigation. They are controlled by:
* The angle set between segments at junctions.
== Surface Streets ==
=== Y Intersections ===

When surface streets meet in a Y formation and we must carefully consider how they are mapped to provide useful navigation instructions. 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.

In the example below, 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.

: [[Image:Jct_Y_ex_aerial.png]]

The description above is how a human would probably describe the situation, but as you can see in the image above, 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 "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, === Intersections ==={| class="straightWikitable floatright" should be the path that remains on the multi| [[File:Jct 3 90.png|x100px|border]]| [[File:Jct 4 90.png|x100px|border]]| [[File:Jct ramp no geo.png|x100px|border]]|-lane roadway, regardless of what the name is| colspan="3"|[[File:4waysplitsplit. To make sure the routing engine understands the proper treatment of the junction, we have to be deliberate with the segment geometry of all png|border|center|169x169px]]|}Basic intersections involve three involved or four road segmentsmeeting at a single point. Some more complex variations resemble H or # shapes. We end up with something like this:
: In all cases it is important to configure these intersections properly. Detailed information is covered in the [[Image:Jct_Y_ex_map.png‎Junction Style Guide/Intersections|Intersections]]article.{{clear}}
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.
Dead Ends (a.k.a. No Exit, Closed, No Through Road, No Outlet) are road segments that simply end, with no continuation or connections at one end. In some areas, a Dead End may be synonymous with a [[#Cul-de-sacs|Cul-de-sac]]. In the US, a "No Outlet" sign may be used to indicate a road which itself is not a dead end, but it only connects to other dead end roads. It can also be used as a "friendlier" alternative to the typical Dead End sign.
Within the Map Editor it is possible to represent a dead end road with multiple segments if there are private driveways or parking lot roads mapped and connected. In that case, only the very last segment is considered the dead end segment.
Make sure that there is a junction indicator (the small blue dot, not just a geometry node) at the very end of the segment. While this one segment does not actually constitute a junction, the small blue dot is a visual indicator to the editor that the end of this segment is properly set up. This is necessary to ensure proper routing out of the segment. See the Cul-de-sac section below on when and how to fix this.
: [[ImageFile:Jct_dead_endJct dead end ex.png|right|border|200px]] This final junction indicator must be located near the end of the road, but it should be located where there is still pavement as not to negatively impact client routes. Waze only considers the road fully traversed if both ends of the segment are fully crossed. If the junction indicator at the end of the segment happens to be at the edge of the pavement (or off of the road surface if aerials are not exactly aligned), it will be very difficult for a driver to cross that junction. A good rule of thumb is to have the end of the segment the same distance from the end of the pavement as it is from each side of the road. : [[Image:Jct_dead_end_ex.png]]
With such a placement, the driver is given a chance to cross that junction indicator for that segment. Also check for the proper u-turn setting as covered in the [[Map Editing Quick-start Guide#U-Turns at the end of dead-end-streets|best practices article on u-turns]].
==== Cul-de-sacs ====
A Cul-de-sac (a.k.a. Court in the US) is a common treatment of a dead end street in a residential neighborhood.
In almost every situation, a cul-de-sac should be treated exactly as a dead end street, with the final junction indicator in the center of the bulb of the cul-de-sac. Be sure the free end of the final road segment has small blue dot displayed at the tip (when not editing or selecting the segment). If there is no blue dot, please correct it by following the steps for [[Creating_and_Editing_street_segmentsCreating and editing road segments#Fix_the_endFix the end-node_on_culnode on cul-de-sacs_and_deadsacs and dead-ends|fixing dead ends]]. : [[Image:Jct_cul-de-sac_ex.png]]
[[Image:Jct_cul-de-sac_ex.png|left|border]]The junction indicator should be located close to the middle of the bulb and NOT near the outer edges. If the end of the segment is positioned along the perimeter of the bulb, there may be difficulty in processing client routes. Waze only considers the road fully traversed if both ends of a segment are crossed. If the end of the segment happens to be on the curb (or off of the road surface if aerials are not exactly aligned), it will be very difficult for a driver to cross end the end of the road segment. With the junction in the middle of the visual road, we give a driver a good chance to cross the end of the segment no matter where they drive within the bulb. The exception to this guidance is given in the next example.{{clear}}
The {| class="Wikitable floatright"| [[Image:Jct_cul-de-sac_island_ex.png|200px|border]]| [[Image:Jct_cul-de-sac_island_ex_road.png|border|200px]]|}This cul-de-sac below, with a small island, should be treated as a basic dead end with no loop. The island can be ignored, as there is no significant routing question for the driver once they get to the cul-de-sac. : [[Image:Jct_cul-de-sac_island_ex.png]]
As for placement of the final junction indicator, here we may get better results by moving the junction out from the true center and over to the outer perimeter of the central island. The shift ensures that the driver has a good opportunity to cross the end of the segment.
However, if the cul-de-sac has a very large bulb with a large island in the middle, it may better be treated as a [[#Loops|Loop]]. A good rule of thumb is if you were standing at the end of the cul-de-sac, can you tell that it is just a cul-de-sac? Or does it look like two different roads? If you see an island, but are not sure if it is significant, leave the Loop out. If "Missing Road" errors occur on the road, then add a Loop.
==== Loops ===<gallery mode="packed-hover">File:U-shaped Road.jpg|U-shaped roadFile:Jct loop bulb.png|terminal or dead-end loop</gallery>Road segments form a loop when you can trace a path from a starting point around to the same point without retracing any portion of the traced path.
Loops are roads ==== Every loop must be made up of three or more segments ====[[File:Loop_3-part_6.jpg|right|150px]]Any loop that does not follow this rule can cause problems for the Waze routing server. If there is no side-street, you can entermust [[Map Editing Quick-start Guide#Splitting a segment|insert an extra junction node]] along the loop. Many new editors will see the extra junction node(s), assume they are not needed, and without reversing course, end up at the same place you starteddelete them. Please educate new editors.
An important Map Editor rule ====Two-segment loops====Two-segment loops create a situation called "same endpoint drivable segments" or "same connection segments". There are two or more ways to get from one junction node to another without going through any other nodes. They can cause a problem for the Waze app regardless of the direction, or other attributes of the segments. This is: '''because the routing server gives your mobile app a list of node IDs only, but the app needs to tell you which segments to drive on. If there are two ways to get from one node to the next without going through any other nodes, then the Waze app might just have to guess. It might guess a detour off the highway through a service road or scenic overlook. Please save Waze from this silliness. Correct two-segment must ''not'' start and end on the same junction node'''loops.
====One-segment loops===={{anchor|Loop_save_errors}}[[File:Dead end loop.png|thumb|right]] One-segment or self-connected loops are often found in basemap areas. It is difficult for Waze editors to create one-segment loops. Depending on the situation, these should be converted to three-segment loops or simple dead-end roads. For more on loops on dead-end roads, please see [[Cul-de-sac#Cul-de-sacs|cul-de-sac]]. It is important to preserve house number data on these segments.===== Fixing one-segment loops=====If this rule is not followedyou try to edit a one-segment loop, but then cannot save the routing server will have difficulty in providing routes into changes, undo your changes and out then try one of the loop. Any loop broken into two segments by a junction will not have this problem.following to fix it:
Please ===Roundabouts and traffic circles===It may be tempting to use the roundabout feature to create a loop shape. Do not do this unless the loop is a roundabout or traffic circle. Roundabouts give special routing instructions, and must not be used for other purposes. To learn more, please see the [[Roundabout]] page for a full discussion of this special type of junction.
DonWith exceptions, don't set these segments as ramps! Watch out for all of the turns you need to restrict. For a full more detailed discussion, see the full [[At-Grade_Connectors|At-Grade Connectors]] page. === Bow tie intersections ==={{Anchor|Bowtie}}The "bow tie" form of an intersection both simplifies and provides enhanced control when a dual carriageway road and a single carriageway road intersect.: [[File:Jct_bowtie.pnggrade connectors]]By reducing the intersection to a single point, we gain control over U-turns and avoid short segments which may introduce complexity and routing issues. The first instinct may be to map the intersection as the road is physically constructed -- using an "H" (a sideways H in this case) where each one-way roadway intersects the cross street. But if that method is used, there is no way to restrict the U-Turn movement from one one-way direction to the other since the center of the "H" carries both U-Turn traffic ''and'' traffic turning from the cross street. But mapped as a bow tie, there is a specific turn arrow that can allow or disallow the U-turn as needed. Additionally, the center segment of the H may introduce complexity to the map. If the cross street changes names at the junction, care must be taken to make the center segment have no name assigned. This will cause the segment to inherit the appropriate name depending on the direction of travel. This center segment is then different from either side so future "select all segments" operations in the editor will not capture this segment which may complicate editingarticle.
Finally, the Waze systems also have difficulty in capturing average speeds for short segments, especially when traffic does not travel across a majority of the segment which may happen in a wide intersection. The center of the H would be totally vertical in the example above, but turning traffic would be traveling in more of a 45 degree angle. Add in the inaccuracy of many consumer GPS chips == Interchanges and wide intersections and you may have traffic never actually driving over the segment for certain movements.ramps ==
An '''NOTE:interchange''' Be aware of the geometry used in the bow tie. If the angles is a road junction where two roads are too steep (45 degrees or greater) a driver traveling along one of the one-way segments may be told to "turn" or "stay" at the intersection instead of receiving no instruction. connected by dedicated roadways, called '''NOTE:ramps''' If the center of the physical "H" is long and/or allows traffic to stop and queue within the median of the divided roadway, a bow tie may . The roads connected by an interchange do not be appropriate. In these cases the segment may be long enough to justify being mapped especially if the intersect one-way roads would have to deviate greatly from their physical location to meet in a single point. == Ramps == Ramps have a very specific purpose in Waze. They are intended to connect segments of Minor Highwaysanother directly, Major Highwaysand if they cross, and Freeways to roads where there are no atthe crossing is grade-grade crossingsseparated.
=== When to use ramps ===
In both cases, the two exiting segments '''MUST''' have identical road types === Ramp and different names from themselves and the entering segment.interchange style ===
== Special Cases ==
=== Transitions ===
{| class="Wikitable floatright"
| [[Image:Jct_transition.png|x150px|border]]
| [[Image:Jct_transition_90.png|x150px|border]]
|}
A transition is a non-junction depicted using a junction node.

: [[Image:Jct_transition.png]] [[Image:Jct_transition_90.png]]
Valid examples of where to use a Transition node include:
# Part of a [[#Loops|Loop Road]]
# Speed Limit Change
An old reason to Before the current house numbering system came into use a , transition node was nodes were used to indicate segments of the road with different aid in house numbering. With the new point numbering scheme being adopted by Waze, this but that is no longer a reason to use transition nodesrequired.
There may be existing Transition transition nodes on the map for other reasons (left like remaining after a connecting road was is deleted, inherited from to the original base map import when things such as rivers and streams created junctions, etc.).
As long as we you are '''certain''' it is not a valid Transition transition node, a superfluous junction node may be [[Map_Editing_QuickMap Editing Quick-start_Guidestart Guide#Delete_a_JunctionDelete a Junction|deleted]]. Doing so will simplify the map, eliminate turn restrictions to maintain, and reduce computing resource needs. Also consider removing the [[Creating_and_Editing_street_segmentsCreating and editing road segments#Adjusting_road_geometry_Adjusting road geometry .28nodes.29|geometry node]] which will replace the junction node you delete, if that geometry node is not needed.
In certain situations it may be necessary to add road segments that are un-drivable in order to provide accurate navigation instructions.

==== Actual ====
A valid use of this technique is at the temporary end of a freeway. As a freeway is built, it is often opened in sections, up to a certain exit. If we map this as a regular freeway segment leading to a ramp segment, no announcement will be made for that final exit, no matter what we name the exit ramp.
This can be confusing if the ramp is set up as a properly signed and numbered exit, especially if a driver is traveling a long distance on this freeway. Imagine traveling down a freeway and seeing your next instruction is "turn left at Main St." You would probably wonder if there was a map error since you shouldn't be making a left turns turn off of a freewaysfreeway.
If we map even just a little of the future path of the freeway, this gives the routing engine a junction which will generate an "exit" instruction at the end of the freeway, thus eliminating any confusion.
Conversely, if we do NOT want an exit instruction at the end of a freeway, ensure there are no road segments extending past the final exit, to ensure the final exit is the only path out of the final freeway segment.

==== Fake ====
''(coming soon)''