HiPDERL: An Improved Implementation of the PDERL Viewshed Algorithm and Accuracy Analysis

Terrain viewshed analysis based on the digital elevation model (DEM) is of significant application value. A lot algorithms have been proposed, including R3 as accurate one and others efficient ones. The algorithm because its comprehensive but time-consuming computation, while are due to proper approximation. However, no capable taking advantage both until which a ‘proximity-direction-elevation’ (PDE) coordinate system named PDE spatial reference line (PDERL) algorithm. original research proves PDERL perfectly by theory experimental results, in comparison with standard, even more than R3. does not mention cases where observer placed grid points, implementation produce very results practice. It important find out correct errors. In this paper, checking for proposed allow further investigation With fundamental ideas unchallenged, an improved HiPDERL. By paper HiPDERL utilizes potential accuracy at cost little efficiency when points.