Helper function factory to classify morphometric features according to a modified version of Wood 1996 page 120
classify_features_ff(slope_tolerance = 1, curvature_tolerance = 1e-04)
A function that can be passed to raster::overlay to classify morphometric features
Slope tolerance that defines a 'flat' surface (degrees; default is 1.0). Relevant for the features layer.
Curvature tolerance that defines 'planar' surface (default is 0.0001). Relevant for the features layer.
Wood, J., 1996. The geomorphological characterisation of digital elevation models (Ph.D.). University of Leicester.