I'm new to QGIS and GIS in general. I'm trying to find a way to create height layers automatically and then use them to clip other layers. In detail: Below is my area of interest. I have a raster containing height information and contourlines. I want to use the areas between the contour lines as clipping masks. Totally convex contours (like the small middle left) I can just fill with "convex enveloping" (I hope that's the English term for it). But others I can't. Especially the borders are difficult.