Fig. 1

A schematic showing each step of the FlowDIR procedure: a Identification of the source; b Identification of the buffer limit; c Method 1, the azimuthal elevation difference; d Method 2, the least cost path
A schematic showing each step of the FlowDIR procedure: a Identification of the source; b Identification of the buffer limit; c Method 1, the azimuthal elevation difference; d Method 2, the least cost path