I want to do some testing with MapCSS styles without firing JOSM for the job. Instead, I want an app (ideally web app) which accepts .osm and .mapcss files as input and, ideally, has a live preview of style changes plus an ability to edit the data. Essentially, I am looking for a MapCSS equivalent of Kosmtik.
If that’s not an option, I am ready to instead install Kosmtik and experiment around with openstreetmap-carto and osm-carto-alternative-colors. In this case, I want:
- Kosmtik installation instructions for macOS Monterey (12) on Apple M1
- Performance is important: does Kosmtik run faster in Chrome than Firefox? If yes, I’ll install Ungoogled Chromium as secondary browser.
- comparison with TileMill (which I have already installed)
- Is it any good for CartoCSS editing? All the openstreetmap-carto folks seem to use Kosmtik, not TileMill – please explain why.
- With TileMill, I noticed it severely hogging my performance (with the app open in Firefox) even while nothing is rendered (it is RAM-heavy and my Mac only has 8 GB).