The Influence of Digital Surface Model Choice on Visibility-based Mobile Geospatial Applications.

In this work we investigate the effectiveness of different types of visibility models for use within location-based services. Zapp, the levels of accuracy of various digital surface representations used by a line of sight visibility algorithm are extensively examined by statistically assessing randomly sampled viewing sites across the 1km(2) study area, in relation to points of interest (POI) across the University of Nottingham campus. LiDAR data by visiting physical sites on each surface model with 14 random point of interest masks being viewed from between 10 and 16 different locations, totalling 190 data points. Each site was ground-truthed by determining whether a given POI could be seen by the user and could also be identified by the mobile device. Our experiments in a semi-urban area show that choice of surface model has important implications for mobile applications that utilize visibility in geospatial query operations.