Talk:Tagging for the renderer

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Actually, when people say "Don't tag for the renderer", what they usually mean is "What you do is wrong and what I do is right, and your arguments are not important". I wish this rule would just be removed. In my opinion, one should tag for the renderer. Rendering is not the only application of OSM, it is still an important one, and to not take that into account (as this rule seems to suggest) is just silly. The better rule would be: Don't tag for a specific renderer, but by all means possible tag for renderability. - Andre Engels 01:34, 1 February 2010 (UTC)

It has been addressed several times especially on the mailing lists, that such use (plain "you do it wrong and I do it right") of the phrase is in error (well, they could be effectively right, but it's at best only a consequence of the real meaning of the phrase). As is written on page, if there are several alternative, correctly descriptive ways to tag the objects, then users should by all means use the tags that get the feature rendered, but they shouldn't use tags that describe something else. It might require a bit extra effort for the first users, if they want their new feature rendered on the main layers, in that they possibly need to file a ticket in Trac, but that step serves to remove duplicate ways to tag the same thing. When users want to (correctly) "tag for the renderer", they (hopefully) in fact want to "use tag combinations for which developers can write simple rendering rules, given currently available software". Alv 08:11, 1 February 2010 (UTC)
Indeed, that's what they do, and that's when they get told that they shouldn't tag for the renderer. The rule may be good, the phrase is totally wrong, and misused 90% of the time it is used. - Andre Engels 13:51, 26 July 2010 (UTC)

Suggest ways to get correct tags rendered

Could we add instructions for what to do instead if a particular rendering bothers you but you still want to tag it correctly? Then it's not just "don't!".

I often wish I knew what to do that might actually be effective. A recent example for me is tagging landuse=port. This is approved on the wiki but does not render in Mapnik. It's obviously correct, but I realised how much better my port looked in Mapnik by keeping it landuse=industrial and reverted my change.

So what I'd like to do is get Mapnik rendering landuse=port. Do I:

  • add a feature request to Mapnik on github or wherever the code is canonically maintained?
  • email the Mapnik mailing list?

[OK, I see on the OSM Mapnik wiki page that they suggest and link to adding an issue on Github. If someone can confirm how effective this really is, I'll add it in to this page.]

I seem to remember reading or hearing somewhere that Mapnik is really slow/behind at dealing with issues and requests, so I'm not inclined to undertake what might be a futile process. However, I genuinely think in this example it's an easy feature to roll out and adds value. It would be nice to know we have an agile process. -- Hubne (talk) 00:29, 7 July 2015 (UTC)

  • "does not render in Mapnik" - is it about default map style? In that case "Standard"/"Default"/"openstreetmap-carto" works better, Mapnik is name of software used to generate maps - not only this style ( ). The place to suggest improvements to Default is at by creating a new issue. Note that landuse=port is used only 160 times, it is extremely unlikely that rendering would be added for that feature. Mateusz Konieczny (talk) 06:04, 7 July 2015 (UTC)
Yes, you are right, Mapnik is simply a rendering engine, that was sloppy of me. I was referring to the default stylesheet, because I care about users coming to the site, which is their first impression of the project, and what they see. Most casual visitors confuse that map/website with "OSM".
The official default stylesheet repo you link to is where I read a discussion in the issue #1630 comments that made me think the process for requesting changes is likely to test my patience. The problem with ruling tags out based primarily on usageis that a tag's usage/application may well be skewed by the fact that the tag has poor rendering support in common stylesheets. That is, mappers like me make a decision to use a broader tag because I want my local friends to be more impressed by their local map. To implement something like landuse=port seems algorithmically cheap. It is a replacement fill colour, not a new one. So I'm saying, in some cases, tags are not popular because of renderer behaviour and there are more considerations than that. --Hubne (talk) 21:49, 19 November 2015 (UTC)
I'm familiar with Github and FOSS development and didn't mean to imply that the (unpaid) maintainers should be able to move faster. Just that there is a huge backlog of feature rendering requests (and good reasons to consider them carefully). --Hubne (talk) 21:49, 19 November 2015 (UTC)

Water tanks blocking addresses

See also Water tanks blocking addresses. Jidanni (talk) 12:08, 26 October 2018 (UTC)

Make items show up now during rescue operations

Well if for some reason the worlds biggest building, mountain, fairgrounds, etc. don't show up...

No. instead let's say during a critical rescue operation for some reason properly tagged bridges aren't showing up. It would seem to make sense to

  • Submit a bug report, and
  • Adjust tagging to make it show up while waiting for the bug to get fixed.

Fixing the bug might take a long time as the software is very complicated and needs a big team. At least we can adjust the tags to make the bridges show up now. Jidanni (talk) 08:51, 23 December 2019 (UTC)

"Adjust tagging to make it show up while waiting for the bug to get fixed." - it is OK as long this is not a mapping for renderer (adding incorrect data/removing correct). Note that everybody may make their own rendering, showing whatever is important for them Mateusz Konieczny (talk) 12:00, 23 December 2019 (UTC)

Legitimate cases of inspecting how the map was changed after your edit

In fact after each edit, the user sees

You just edited OpenStreetMap!
Thank you for improving the map around Nibblesburg.
Your changes should appear on OpenStreetMap within a few minutes.

Therefore we see there is never a need to waste time and inspect how the map now looks after our edit, as if we don't trust the message.

So perhaps list "legitimate cases of inspecting how the map was changed after your edit". Jidanni (talk) 09:57, 19 February 2020 (UTC)

I added "It is also perfectly fine to use various renderings as one of tools to find mistakes in what is mapped. Just remember that it is a tool, not a final and ultimate arbiter of a correct mapping." to the last section Mateusz Konieczny (talk) 10:47, 19 February 2020 (UTC)

Rendering tradeoff advice on Key:bridge#Naming

Key:bridge#Naming mentions rendering tradeoffs. Jidanni (talk) 02:25, 23 March 2020 (UTC)

Not sure what the images are showing

Hi, I'm new here. It might be evident to people more experienced, but in the images in this article, what is inaccurate about the maps? I would like to clarify the caption with what is being shown. (I just took a crack at it) --P8 (talk) 00:17, 25 September 2021 (UTC)

Thanks for improvement! It is very valuable as it is rare to have people both not very experienced (so able to spot such issues) and willing to report issues or even fix them. Thanks for this help! Mateusz Konieczny (talk) 19:01, 25 September 2021 (UTC)


The page title should be amended to more accurately say "Tagging incorrectly to suit the renderer"

All tags are 'for the renderer' otherwise maps would be just black lines & dots.

A few tags, such as Key:layer, are only for the purpose of rendering accurately.--DaveF63 (talk) 15:44, 27 June 2022 (UTC)

Shortened and misleading form is typically used but I would support moving to such more accurate title Mateusz Konieczny (talk) 17:37, 27 June 2022 (UTC)
"A few tags, such as Key:layer, are only for the purpose of rendering accurately" - not only, it can be also used for some forms of data analysis and QA Mateusz Konieczny (talk) 15:41, 15 July 2022 (UTC)
In what context?--DaveF63 (talk) 17:27, 15 July 2022 (UTC)
@DaveF63: Recently in OSMUS Slack, there was an offhand mention of "lying to the renderer", which I find to be just as elegant as the classic original but more accurate. – Minh Nguyễn 💬 23:58, 10 August 2022 (UTC)

I'm not sure I'm a fan of the new title "Lying to the renderer". When I find beginner mappers tagging for the renderer, I let them know what they did, and then link this page for further information / some authority. Obviously, many beginners believe improving the appearance of openstreetmap-carto is the primary purpose of OSM. So "lying" is a bit too accusatory in that context, it implies they knowingly did something wrong. – AndrewSuzuki 04:03, 29 August 2022 (UTC)

New Page Title

This page has been recently renamed. I suspect that this renaming will make it much less effective that it was before, which is a shame. If you want someone to change the way they do things, then "excuse me, would you mind perhaps doing X in future instead of Y because of Z" is going to be more effective than "Oi <bad word redacted>! Do X!". SomeoneElse (talk) 14:11, 28 November 2022 (UTC)

Yeah, count me surprised as well. While User:Mateusz Konieczny did obliquely reference some SOTM discussion, I think it's a major change that should have been discussed onwik. I also find the new title ineffective and unnatural; it's been known as "tagging for the renderer" since forever and should stay that way. Duja (talk) 19:39, 2 December 2022 (UTC)
Feel free to move page title back if you think that it is an improvement - right now both versions have similar support in this wiki discussion and given that STOTM discussion is not linked/reviewabled/particitable/documented it should be treated as extremely discounted. Mateusz Konieczny (talk) 11:34, 3 December 2022 (UTC)
It's now back as "Tagging for the renderer" again. Thanks! SomeoneElse (talk) 22:09, 23 December 2022 (UTC)

Proper way to map giant letters

An improper mapping of non-existent landuse=commercial and natural=sand areas to paint lettering on a sports field. This is improper mapping because there are not actually commercial or sand areas in these locations, the tags were just chosen for their fill colors in a particular renderer.

Yes. But do mention the proper way, when there's letters so big that they can be read from space, and that's the Ground truth.

Probably a new tag: character=B size=3 perhaps? One for each letter. Of course mention if it will get rendered...

Jidanni (talk) 08:15, 25 August 2023 (UTC)

Editing motivation

We are adding detail to the map so that the map will be more useful to others, and us, sometime soon.

If it takes longer for our efforts to appear than submitting corrections to Google Maps takes, then OpenStreetMap has lost.

Jidanni (talk) 08:24, 25 August 2023 (UTC)

"It is also perfectly fine and normal to be motivated by seeing something displayed and rendered. " Mateusz Konieczny (talk) 09:08, 25 August 2023 (UTC)
Resolved: More Jidanni threads about already done things Mateusz Konieczny (talk) 07:30, 3 October 2023 (UTC)

Editors could show what this will look like

It would be neat in e.g., iD, if there were a preview button, that would show "the current combination of tags you have chosen will look like this on the map, using the Standard Layer."

That way one needn't keep trying to publish (save the edit) and refresh (CTRL+F5 etc.) the map to find out.

That way, if iD suggests


one will know earlier that it won't show up on the map.

All I am talking about is early warning that the tags one chose will cause such facilities to perhaps be delayed in mapping by 10 years:

  • the time it might take for the rendering program to be improved to render it, or
  • the time other mappers might remap it, which would have instead been one year, if they didn't see that it was mapped already, at least in iD.

Jidanni (talk) 07:06, 3 October 2023 (UTC)

That would encourage intentionally wrong mapping for renderer so is a bad idea Mateusz Konieczny (talk) 07:29, 3 October 2023 (UTC)
"early warning that the tags one chose will cause such facilities to perhaps be delayed in mapping by 10 years" - no, such warning may discourage mapping them (you confuse mapping with rendering it seems: but not mapping them also makes rendering less likely) Mateusz Konieczny (talk) 07:29, 3 October 2023 (UTC)