caa a22 4500 605540667 CHVBK 20210128100912.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s00371-014-0936-3 doi (NATIONALLICENCE)springer-10.1007/s00371-014-0936-3 Optimizing line-of-sight using simplified regular terrains [Elektronische Daten] [Troy Alderson, Faramarz Samavati] In this work, we explore a set of techniques for speeding up line-of-sight queries whilst attempting to maintain accuracy. Line-of-sight queries, which test if two entities can see each other over a 3D terrain model, are an important operation in several applications. Given enough entities and a large enough terrain, computing these queries can be expensive. We apply reverse subdivision methods to simplify the terrain model and speed up the queries, including a novel feature-aware reverse subdivision scheme. To counteract the loss of accuracy due to simplification, we also examine the problem of where entities should be placed after terrain simplification to increase accuracy. Using iterative methods that attempt to maximize accuracy, we show that room for improvement exists over the standard projection method. Then, using residual multiresolution vectors, we develop a relocation method designed to maximize accuracy over simplified terrain models. Finally, we present a fast line-of-sight algorithm that combines these techniques with pre-existing algorithms. Springer-Verlag Berlin Heidelberg, 2014 Line-of-sight nationallicence Terrain simplification nationallicence Multiresolution nationallicence Subdivision nationallicence Reverse subdivision nationallicence Alderson Troy University of Calgary, Calgary, Canada aut Samavati Faramarz University of Calgary, Calgary, Canada aut The Visual Computer Springer Berlin Heidelberg 31/4(2015-04-01), 407-421 0178-2789 31:4<407 2015 31 371 https://doi.org/10.1007/s00371-014-0936-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00371-014-0936-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Alderson Troy University of Calgary, Calgary, Canada aut NATIONALLICENCE 700 1- Samavati Faramarz University of Calgary, Calgary, Canada aut NATIONALLICENCE 773 0- The Visual Computer Springer Berlin Heidelberg 31/4(2015-04-01), 407-421 0178-2789 31:4<407 2015 31 371