Ability to export plans as high resolution pngs.

[Kandico]

This is self explanatory, being able to export plans as high res pngs would be useful for every user

[dabreegster]

Do you mean something like setting the map viewport possibly kind of large / zoomed out to cover a wide area, but generating a large image of that entire area more zoomed in?

Possible approaches:

• I've tried https://github.com/watergis/maplibre-gl-export before without luck (even their current hosted demo breaks for me).
• https://larryhudson.io/protomaps-maplibre-screenshot/ describes an approach to capture the <canvas> as an image, but we use maplibre markers, rendered as DOM elements, for some things, so that won't work.
• I've seen some headless maplibre rendering server project somewhere, but can't find it...
• https://docs.maptiler.com/sdk-js/examples/helper-screenshot/ has a helper for this, worth trying!
• Taking a direct screenshot in the browser? But people can already do this manually, and presumably the goal is to take higher-resolution images

[dabreegster]

I take it back, we only use markers for a few UI controls (drawing routes / polygons). We use symbol layers in plenty of places, but I believe those are rendered in the OpenGL canvas.

[dabreegster]

Proof-of-concept is looking good in the screenshots branch:

To do this for real, need to stitch together the images in the browser directly (rather than montage row1col1.png row1col2.png row2col1.png row2col2.png -tile 2x2 -geometry +10+10 stitch.png on the CLI) and figure out the controls for specifying the bounds and zoom level.