<div dir="ltr">Greetings, lofty KDE Marble Devs!<br><br>Can anybody advise me on how I could programmatically create an overlay (to work with Marble) consisting of a 10 km "coastal band"?<br><br>Basically I want to highlight--as precisely as can be done--all land that is less than 10 km from the ocean or ocean-connected seas. (Basically the two "inland" Asian seas do not count, nor do lakes and rivers.) Doing this with a flat map is difficult enough (although I have done it)... with something like Marble, I am not even sure where to begin. I figured though, if anybody knew, it would be the devs working programming magic despite the math-heavy projection-defined world of... world maps.<br>
<br>At the end of the day, I'd basically like to be able to zoom in as far as Marble lets me and be able to tell whether particular cities, lakes, or other features are inside or outside this "highlighted coastal zone".<br>
<br>If this is basically impossible, can somebody suggest some way to achieve the same ends? Arguably an impractically huge (highest resolution Blue Marble size) political map would do the trick. I already have a Python program that can create such a highlight layer from a properly preprocessed Robinson projection map. But as far as I can tell, sufficiently high resolution political maps don't exist outside of Marble, Google Maps/Earth, NASA's Worldwind and similar programs.<br>
<br>I would be immensely grateful if somebody could point me in the right direction.<br><br>Respectfully,<br><br>Danuvius<br></div>