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Opened 12 years ago

Closed 7 years ago

Last modified 7 years ago

#3531 closed defect (fixed)

Validator - false positives in "way end node near other way"

Reported by: bilbo Owned by: dmuecke
Priority: normal Milestone: 14.01
Component: Core validator Version: latest
Keywords: unconnected_way Cc: AM909, MikeyCarter

Description (last modified by mdk)

Check for "way end node near other way" is useful, however in some areas it finds many false positives.

Minimal distance to trigger this warning seems to be 10 (by default).

But what unit it is? when the preference is read, the number is divided by some arbitrary number 6378135.0
What is meaning of that number? No documentation in the source

I've collected some examples of false positives found by validator, along with some ideas how to avoid them:

validator-deadend.png - T-junction near end of way

There is branching (T-junction) close to end of way. This shows false alarm, even though the way in warning is connected to the way with the endnode.

validator-platform.png - Parallel railway tracks or platforms

Railway platforms or tracks running in parallel - these can be as close as 5 meters.
Have some smaller distance to trigger the warning, if both ways (the one with end node and the one close to the node) are parallel or very close to parallel

validator-powerline.png - highway end node close to powerline
validator-stream-road.png - highway end node close to stream

Sometimes features are running quite close to each other "by design".
Power lines often are placed with little regard of what is below them and endpoint of highway ending up near powerline is surely not connected to it.
Sometimes stream run right behind the streets (the streets are ended just before the stream) and they are also not connected

Therefore for "incompatible" features (highway vs waterway, powerline vs waterway/railway/highway) that should not be probably connected
(highway connected to the powerline does not make sense), the distance should be lower too.

I think for these cases, some lower distance threshold (one quarter by default, perhaps ....) should be used

Attachments (7)

validator-deadend.png (2.2 KB) - added by bilbo 12 years ago.
validator-platform.png (1.9 KB) - added by bilbo 12 years ago.
Parallel railway tracks or platforms
validator-powerline.png (3.3 KB) - added by bilbo 12 years ago.
highway end node close to powerline
validator-stream-road.png (817 bytes) - added by bilbo 12 years ago.
highway end node close to stream
validator_WayEndNodeNearWay_example.osm (1.2 KB) - added by skyper 10 years ago.
example file
falsePositive.osm (1.6 KB) - added by mdk 9 years ago.
It looks like this issue is not so clear, but it huts me every day. So I add a more clear example with a highway near a poweline, a waterway and a barrier. I hope this will help to solve the problem.
waterways.osm (69.8 KB) - added by skyper 7 years ago.
another example file

Download all attachments as: .zip

Change History (36)

Changed 12 years ago by bilbo

Attachment: validator-deadend.png added

Changed 12 years ago by bilbo

Attachment: validator-platform.png added

Parallel railway tracks or platforms

Changed 12 years ago by bilbo

Attachment: validator-powerline.png added

highway end node close to powerline

Changed 12 years ago by bilbo

Attachment: validator-stream-road.png added

highway end node close to stream

comment:1 Changed 11 years ago by dmuecke

Owner: changed from team to dmuecke
Status: newassigned

comment:2 Changed 11 years ago by skyper

Keywords: validator added

I think in all these example there should be a warning as long as the highway does not end with noexit=yes, but it should not be refered to a way with a differences in layer=* .

Version 0, edited 11 years ago by skyper (next)

comment:3 Changed 10 years ago by bastiK

Ticket #4363 has been marked as a duplicate of this ticket.

comment:4 Changed 10 years ago by skyper

Component: Core validatorCore
Keywords: way node added

Validator is in Core now

comment:5 Changed 10 years ago by skyper

Component: CoreCore validator
Resolution: fixed
Status: assignedclosed

Seems to be fixed

r3992

comment:6 Changed 10 years ago by skyper

Resolution: fixed
Status: closedreopened

Sorry. Validator does not find any "way end node near other way" right now

comment:7 Changed 10 years ago by skyper

I have another example with barrier=fence

Changed 10 years ago by skyper

example file

comment:8 Changed 10 years ago by skyper

Ticket #5837 has been marked as a duplicate of this ticket.

comment:9 Changed 10 years ago by skyper

Validator also warns about "way end node near other way" with untagged ways which are only part of landuse-relations as "other way" . Think this is a false positiv, too.

r4074

comment:10 Changed 10 years ago by skyper

Ticket #4257 has been marked as a duplicate of this ticket.

comment:11 in reply to:  9 Changed 10 years ago by skyper

Replying to skyper:

Validator also warns about "way end node near other way" with untagged ways which are only part of landuse-relations as "other way" . Think this is a false positiv, too.

r4074

Everything except the unntagged way is still an issue. Please, do check the main tag of both ways and filter to only check for ways with the same main tag. Thanks

r4137

comment:12 Changed 10 years ago by skyper

Ticket #5435 has been marked as a duplicate of this ticket.

comment:13 Changed 10 years ago by simon04

Ticket #6313 has been marked as a duplicate of this ticket.

Changed 9 years ago by mdk

Attachment: falsePositive.osm added

It looks like this issue is not so clear, but it huts me every day. So I add a more clear example with a highway near a poweline, a waterway and a barrier. I hope this will help to solve the problem.

comment:14 Changed 9 years ago by mdk

Description: modified (diff)

Ping :-)

(BTW why dose attaching a file did not effect 'last change date' of the issue in trac?)

comment:15 Changed 9 years ago by simon04

Keywords: unconnected_way added; validator way node removed

comment:16 Changed 9 years ago by skyper

Found another issue:

a bridge (node) which ends near a landuse=farmland (way)

This should not be a problem (no warning).

EDIT: Already reported in comment:9

Last edited 9 years ago by skyper (previous) (diff)

comment:17 Changed 9 years ago by skyper

Ticket #7742 has been marked as a duplicate of this ticket.

comment:18 Changed 9 years ago by skyper

Cc: AM909 added

From #7742 AM909:

In r5181:

The validator reports "way node end near other way" when it shouldn't - specifically for objects of different types. Examples:

  • A road (highway=*) that ends near an admin boundary (boundary=administrative + place=city + ...)
  • A road (highway=*) that ends near a river (waterway=river).
  • A road (highway=*) that ends near a power line (power=line). This probably doesn't happen if the power line has layer > that of the road, but few people seem to do this, and the validator doesn't report power lines crossing roads of the same layer, so it is apparently assumed that power lines are layer=6.
  • A fence (barrier=fence) that ends near a road (highway=*).

Basically, it seems this check is designed to find ways that should intersect, but don't. It should, therefore, limit itself to types of ways that should actually intersect (like those with the same main key, though there may be some others).

comment:19 Changed 9 years ago by anonymous

Ticket #7893 has been marked as a duplicate of this ticket.

anonymous:

I often see how the validator reports e.g. a footpath joining a street near a tram line, which leads to said warning. The warning is not correct as connecting a footpath to a railway is wrong. It should not report the warning for such heavily dissimilar ways.

Last edited 9 years ago by skyper (previous) (diff)

comment:20 Changed 8 years ago by anonymous

Another edge case that should be avoided...

I mapped the entrance to an underground parking garage from imagery as a tunnel just going off the end of the road that doesn't connect to anything. The tunnel segment ends near another road on the surface and throws this validator error. It should ignore all ways that are on a different 'layer' as indicated by the layer tag. A similar thing should probably also be done for the 'level' tag which is used for indicating which "floor" something is on for indoor mapping.

comment:21 in reply to:  18 Changed 8 years ago by skyper

Replying to skyper:

From #7742 AM909:

In r5181:

The validator reports "way node end near other way" when it shouldn't - specifically for objects of different types. Examples:

  • A road (highway=*) that ends near an admin boundary (boundary=administrative + place=city + ...)
  • A road (highway=*) that ends near a river (waterway=river).
  • A way (highway=*,waterway=* or railway=*) that ends near landuse=* or natural=*.
  • A road (highway=*) that ends near a power line (power=line). This probably doesn't happen if the power line has layer > that of the road, but few people seem to do this, and the validator doesn't report power lines crossing roads of the same layer, so it is apparently assumed that power lines are layer=6.
  • A fence (barrier=fence) that ends near a road (highway=*).

Basically, it seems this check is designed to find ways that should intersect, but don't. It should, therefore, limit itself to types of ways that should actually intersect (like those with the same main key, though there may be some others).

+1

All cases which lead to incorrect mapping and to misses of the valid cases as you get too many false warnings.

comment:22 Changed 7 years ago by Don-vip

Ticket #9395 has been marked as a duplicate of this ticket.

comment:23 Changed 7 years ago by simon04

Resolution: fixed
Status: reopenedclosed

In 6515/josm:

fix #3531 - validator: unconnected ways: handle highway/railway/waterway/natural+landuse/power separately

comment:24 Changed 7 years ago by simon04

In 6518/josm:

see #3531 - validator: unconnected ways: ignore highway/railway=platform

comment:25 Changed 7 years ago by Don-vip

Milestone: 14.01

Changed 7 years ago by skyper

Attachment: waterways.osm added

another example file

comment:26 Changed 7 years ago by skyper

Resolution: fixed
Status: closedreopened

Thanks for the improvements but I am sorry, I did find two more problem concerning waterways and water:

  1. If a waterway runs into a lake and starts on the other side again I get a warning, if the lake is small and/or both ways are close.
  2. If you have a short part as tunnel in between (bridges are quite rare) we still have the same problem as we had with highways.

Please use the attached example

comment:27 Changed 7 years ago by simon04

Resolution: fixed
Status: reopenedclosed

In 6667/josm:

fix #3531 - validator: unconnected ways - skip "Way end node near other way" if connected

comment:28 Changed 7 years ago by Don-vip

Ticket #5277 has been marked as a duplicate of this ticket.

comment:29 Changed 7 years ago by Don-vip

Cc: MikeyCarter added

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