Improvements to the Humanitarian Data Model CartoCSS

[cgiovando]

Proposed by: Cristiano Giovando
Summary: Improvements and refactoring of road styles, icons and labels for the Humanitarian Data Model map style. Work should be coordinated with other OSM cartographic design efforts (OpenStreetMap Carto, OSMIc, Maki).
Skills Required: cartographic design, icon design, information architecture
Possible Mentors: Yohan Boniface (@yohanboniface)
Notes: project Website https://github.com/hotosm/HDM-CartoCSS/

[cgiovando]

@yohanboniface @skorasaurus we are thinking of including HDM-CartoCSS as a project for Google Summer of Code ideas. Would you mind summarizing open issues and proposed enhancements that could be the worked on by a student in a 3 months period? We would also need to know what skills are required and if one of you could mentor the student during the summer. Thank you!

[yohanboniface]

There are three main groups of issues:

• roads
• labels
• icons

Plus a bunch of various rendering improvements/refinements.

On the road side, I think a refactoring is needed (there are some glitches), plus there is a recurrent request from the community to better display the "surface vs hierarchy" information.
On the label side, we are mainly talking about adding some, plus refining a bit to avoid duplicates on metatiles junctions.
On the icon side, which is certainly the bigger part, we are talking about doing more icons.

As a general concern, I want to make clear that all those points are hard ones, and this is why they are not done yet. Hard is the sense that there is generally not an obvious solution around, and so it means trying, thinking, arguing, a lot, more than actually doing. Maybe on the icon side the perimeter is a bit less chaotic.

Another important point is that a rendering is not made for rendering all available data, it's an editorial choice that serve a purpose, so having someone that would take the issues one by one an adding the requested feature on the map would not help; if you look at the issues list, you will see that a part of them are from the OSM community that uses the HDM rendering for other purposes than humanitarian related activity. There is a mantra that says something like "info + info + info = noise", and we don't want to reach this point. In other words, the challenge about the rendering is a lot in making arbitration in what to render and what not.

Also, if we aim to be consistent, we would run a cleaning of the HDM preset in the same time.

Another point could be to work on moving the code to a vectortile based data source (instead of osm2pgsql Postgres database), but this would need a bit more maturity of the OSM vector stack, and setting up a dedicated stack somewhere (can be on the OSM fr servers, but also anywhere else, as soon as we control it; I'm planning to do it at some point anyway).

So, as you can see, various different skills can be involved: pure map design, icon design, information architecture in one hand, system administration in the other hand.

In case we decide to go for a GSoC, I'm happy to mentor it.

[althio]

For reference on icons.

There is ongoing work on icons at OSM main-default carto style gravitystorm/openstreetmap-carto#1165
The work is to move to SVG and propose new design with most active contributor @nebulon42.

Another floating idea is to share icons across projects
gravitystorm/openstreetmap-carto#659

[nebulon42]

Thanks for notifying me. As @althio wrote there is currently an effort to refresh the icon set of the openstreetmap-carto style and move all POI icons to SVG. It would be nice if this effort would also lead to increased collaboration and/or consistency of icons between different carto projects (where possible) such as HDM and openstreetmap-carto.

For my new icons I already was heavily inspired by Maki and the extension Nori that HDM uses. I planned to also try to extend efforts to HDM, but wanted to wait until openstreetmap-carto icons have reached a certain level of maturity.

I have bundled all new icons together at nebulon42/osmic. All contributions are happily accepted. While this is not necessarily meant as central icon set it could evolve into one if there are overlapping needs and bundled effort. This place could also be suitable for the "trying, thinking, arguing" part, which will definitely play a big role in icon-efforts.

I'm not trying to hijack this issue, the discussion if there could be any bundled effort and how it could look like should maybe happen elsewhere. For GSoC: If there is a project I'm happy to offer icon-related support. Mentoring should be done by a maintainer though.

cc @math1985

[cgiovando]

Thank you all (@althio @nebulon42 @yohanboniface) for the feedback.

Yohan, can you please propose a summarized description of work based on this discussion? Two or three sentences should be enough. Cheers!

[skorasaurus]

As Yohan eloquently explained, there are many possible improvements but
these some of these improvements need skills not just technical but also a lot of communication.

Regarding communication,
We need to ensure that any new tags we are selecting to render are
agreed upon by many of the actors in HOT ecosystem including actors out in the field and those involved in activations and OSM communities HOT-francophone communities that have utilized the HDM/HOT rendering.

Additionally, I'd highly encourage that some international user testing or communication is done so that any new icons are understood across multiple culture and languages, not just the Anglophone world.

I also agree with Yohan that a review of the HDM Preset would be needed with any tagging related work.

Lastly, there's a lot of different work that can be done, so a project can and should be quite narrowly focused so the developer doesn't burn out. :)

[dalekunce]

+1 for this as a Summer of Code Project. I've spent a bunch of time working on converting the HDM style to something renderable via MapBox Streets. I've got the basic look and feel down but still need to handle all of the POIs. I would love to hand this off to someone to run with. I'd also be willing to host the potential student at the American Red Cross if they need space/computer to work.