An Efficient External Memory Algorithm for Terrain Viewshed Computation
نویسندگان
چکیده
منابع مشابه
Efficient viewshed computation on terrain in external memory
The recent availability of detailed geographic data permits terrain applications to process large areas at high resolution. However the required massive data processing presents significant challenges, demanding algorithms optimized for both data movement and computation. One such application is viewshed computation, that is, to determine all the points visible from a given point p. In this pap...
متن کاملAn Efficient Algorithm to Compute the Viewshed on DEM Terrains Stored in the External Memory
Nowadays, there is a huge volume of data about terrains available and generally, these data do not fit in the internal memory. So, many GIS applications require efficient algorithms to manipulate the data externally. One of these applications is the viewshed computation that consists in obtain the visible points from a given point p. In this paper, we present an efficient algorithm to compute t...
متن کاملA Fast Algorithm for Approximate Viewshed Computation
Given a terrain model, the viewshed from a viewpoint is computed as the set of X-Y positions of a point target such that the target is visible. We introduce a novel approach to the computation of accurate viewshed approximations. Our algorithm relies on the computation of an approximation to the so-called line-of-sight (LOS) function. This function is defined over target X-Y positions, and is t...
متن کاملA Parallel Algorithm for Viewshed Computation on Grid Terrains
Viewshed (or visibility map) computation is an important component in many GIScience applications and, as nowadays there are huge volume of terrain data available at high resolutions, it is important to develop efficient algorithms to process these data. Since the main improvements on modern processors come from multi-core architectures, parallel programming provides a promising means for devel...
متن کاملAn efficient external sorting algorithm
This paper presents an optimal external sorting algorithm for two-level memory model. Our method is different from the traditional external merge sort and it uses the sampling information to reduce the disk I/Os in the external phase. The algorithm is efficient, simple and it makes a good use of memory available in the recent computer environment. Under the certain memory constraint, this algor...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: ACM Transactions on Spatial Algorithms and Systems
سال: 2016
ISSN: 2374-0353,2374-0361
DOI: 10.1145/2903206