![]() ![]() We already know these polygons generally overlap and then we’ll also want to play with neighbourhood relations in between tiles (i.e. Now it gets a little more implementation specific, I’ll try to describe how I did it but I’m pretty sure there might be better approaches as well. We have the polygons so now what we have to do is (basically) to rasterize these polygons, which will yield us a set of tiles, and visualize those tiles. Wikipedia defines rasterization as “the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (pixels or dots).” So now we have the polygons, what’s next? I also ordered them bottom to top so the latter will be on top of former and it all results in that top down shot above. Contour layer elevation=200 for mountains.Landuse layer for forests (I didn’t filter by type/class as landuses are mostly national parks at this level).I created my demos using zoom level 10 as it felt the best for big areas, and at z10 I used For example, “elevation 200” would work for all levels above 10 but it won’t work for zoom level 9 as it uses 500 meter intervals and there won’t be “elevation 200” in that level. Mountains though a little bit trickier as contour layer uses different intervals on each zoom level so this value kinda depends on it. Land is easy, elevation=0 should be land, right? Now our goal is to find the polygons/heights we want to define as “land” and “mountain”. ![]()
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