This is my workspace, it adds elevation to lake polygons and river lines from a DEM. Lakes are calculated by clipping the raster and getting median elevation, meanwhile river lines are draped onto a surface.
Most of the time my data does not contain any lines, but the SurfaceDraper still creates a surface, which can take a while - is there a way to improve performance by preventing the SurfaceDraper from doing anything unless it receives at least one DrapeFeature?
