Digital surveying of large-scale multi-layered terrain

Abstract

Digital terrain surveying is the exploration of terrain reconstructions and quantitative analysis of their properties. Out-of-core techniques, such as terrain streaming, are required to perform surveying on large-scale terrains at interactive frame-rates.The polyline based surveying tool from PRo3D, one of the state-of-the-art solutions for planetary geology, was implemented in our tool Visionary. In PRo3D the polylines are subsampled using fixed-rate subsampling (FRSS) at equidistant points. Our method uses variable-rate subsampling (VRSS) and shared-edge detection (SED) as an improvement that finds exact results when neighbouring primitives are hit. Furthermore, an uncertainty metric On-Data Ratio (ODR) was presented to raise awareness about the uncertainty of these measurements. Visionary was developed in the Unity game engine to evaluate if it is a suitable framework for such a specialized tool. We evaluated our implementation against Pro3D.