What I would like to achieve is an A4 print out of an OSM map with a polygon outline printed on top.
This would come from a web application. Where a user can centre the map, upload a polygon. Which I can do already using Leaflet.js and Mapbox.
I have no idea where to start on this, but I need to take the tiles from the current "view" which would be easy enough, but then I need to scale them, draw the polygon ontop, and then print to a PDF which gets emailed back.
Does anyone have any suggestions on how to achieve this in an automated way?