Scale map features

[zdila]

Hello,

Is there a way to scale vector map features? Something like simlulating browser's zoom. After the scaling, the map bounds and zoom level would stay the same, just font sizes, icon sizes, line thickness, patterns, etc. would increase. I need it for acessibility.

[CommanderStorm]

There is nothing that is build in, but if you use global state you can add it to your style to make it more customised this way as a setting.
You usually don't care about every feature the same way (for example for an university map you likely care more about buildings/walkways/Transit than roads/parking lots...).
A global scaling thing would likely fail the users that this is trying to improve the experience for.

Do note that global state is sort of a moving target, so if you find an area that is not quite as polished I encorage you to jump into the code and submit a PR.
That part of the codebase is quite easy to work with imo.

CC @mizmay if there is an option/feature that we am misssing.

[zdila]

I was hoping for some setting that would work for all vector maps. Something like Ctrl + + does in browsers, but only for the map. Visually impaired people need to enlarge all features more or less the same way.

[CommanderStorm]

You generally cannot enlarge all feautres.
You will need to pick between feautures

Lets pick an example:

If I were to "just enlarge all features", there would need to be a tradeoff. Does the cartographer care more about the benches or the trees? The rendering engine won't know that, the cartographer will.
Letting the cartopgrapher decide what to show here is a good idea than trying to do magic..
Maps are always about dropping and simplifying some features at some level..

Here is more on the topic of a11y and things.. #53

[mizmay]

I have implemented this, for labels.

As Frank says, it is not built-in, you'll have to manage it dynamically in code. Also it is quite tricky to write label styles that work at variable sizes, and you wouldn't want it for other map features. If you need it for accessibility requirements, this is how you would do it.

A good practice that helps informally is to scale your labels effectively with zoom, so they are legible when the user zooms in. But of course this doesn't work if you have a client that needs a map they can manually scale.

[mizmay]

I wouldn't rule this out as a future feature, the problem right now is the complexity of how fonts can be implemented makes a clean universal implementation impossible.