I am using OSM data to build a network for traffic simulation (using SUMO). I often notice errors in the data when it comes to the available number of lane, I have fixed one as an example Changeset 32608483.

In the linked case, I am guessing it is okay to make the change but I have some other cases where a single way has its number of lanes change (some part of the way has 2 lanes, some part has 3, some other has 4 when the lane reaches an intersection). In this case, for the simulation purpose, I need to split this into three different ways, with the correct number of lane for each of them.

Is it okay to make this kind of split and commit them to the OSM database? In some cases, it can significantly increase the number of ways without improving the quality of the map render.

asked 15 Jul '15, 06:38

BLUG_Julien's gravatar image

BLUG_Julien
61115
accept rate: 0%

edited 15 Jul '15, 11:22

sleske's gravatar image

sleske
4.0k115477

1

Hi, and welcome to help.openstreetmap.org. You mention "sumo" - I added a link. Is that the right link (SUMO by DLR)?

(15 Jul '15, 11:23) sleske

It is, thanks for adding the link.

(15 Jul '15, 16:47) BLUG_Julien

Yes, splitting the way is the right solution. It is established practice that ways are split whenever an attribute changes - different name, different width, or just different speed limit.

in some cases, it can significantly increase the number of ways without improving the quality of the map render.

This is not relevant - tagging for the renderer is generally not a good idea (plus in this case it does not even cause problems for the renderer, because renderers know that split ways should usually be combined for rendering). If the number of lanes change, split the way.

Note: While splitting, take care not to remove any data:

  • copy over all tags that apply to both of the new ways
  • make sure membership in relations is preserved

Most editors should help you with this, but it cannot hurt to check.

permanent link

answered 15 Jul '15, 11:18

sleske's gravatar image

sleske
4.0k115477
accept rate: 25%

edited 15 Jul '15, 11:26

Thanks, this is telling me what the next steps are for me, one thing I forgot to ask is if there is any way in the OSM database to tell which lane of a way connect to which lanes of the previous and following ways. By connect, I mean either through a merge or a split, not by typical lane change. Should I maybe ask this as a separate question?

(15 Jul '15, 16:49) BLUG_Julien
2

Take a look at the turn lane tagging. As an example if the right lane disappears and there are merge arrows on the pavement then the section where the arrows are can be tagged with "turn:lanes=none|slight_left"

http://wiki.openstreetmap.org/wiki/Key:turn:lanes

For what it is worth some OSM based routers use this type of tagging to help provide lane guidance.

(15 Jul '15, 23:43) stf

Is it okay to make this kind of split and commit them to the OSM database?

Yep. Nothing wrong with that. That's what you're supposed to do. Ways are often split in OSM when an attribute changes.

In some cases, it can significantly increase the number of ways without improving the quality of the map render.

Nothing wrong with increasing the number of ways in the database. The world is big. It'll take a lot of time & data to map it all.

permanent link

answered 15 Jul '15, 17:44

rorym's gravatar image

rorym
5.3k144898
accept rate: 11%

Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

By RSS:

Answers

Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text](http://url.com/ "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:

×139
×43

question asked: 15 Jul '15, 06:38

question was seen: 1,926 times

last updated: 15 Jul '15, 23:43

powered by OSQA