Spatial data comes up in many areas of computer science, like geographic information systems gis, robotics, computer graphics, virtual reality, as well as in other disciplines like. On earth, such as natural and construted features like ocean, lake, pond etc. State records administrator the acting state records administrator, jan mccormick at 5038086655, is responsible for identifying any privacy issues related to spatial data. Real world objects can be divided into two abstractions.
The great diversity of spatial data structures is one of the reasons why exchanging spatial data between gis is problematic. Spatial data structures data structures that organize geometry in 2d or 3d or higher the goal is faster processing needed for most speedup techniques primary applications. Visualization of spatial data structures on different levels of. The term quadtr e is often used to describ e man y elemen ts of this class of data structures. In particular, w e fo cus on hierarc hical data structures. In all cases, the geometry of these data structures consists of sets of coordinate pairs x, y. Essentially adding the attribute database to the spatial location. Such methods decompose the space from which the spatial data is drawn e. The basic spatial data model is known as arcnode topology.
As we shall see, the term quadtree has taken on a generic meaning. Computer graphics, image processing and gis addisonwesley series in computer science samet, hanan on. Pdf spatial data structures kristin stock academia. Consequently, their understanding is a prerequisite for an effective construction of important components of a spatial database system like spatial index structures, optimizers for spatial data, spa. Spatial data, also known as geospatial data, is a term used to describe any data related to or containing information about a specific location on the earths surface. This paper proposes a division of data structure visualization into four levels of abstraction, and shows how these abstractions can be taken into account in the. An overview is presented of the use of spatial data structures in spatial databases.
They are based on the principle of recursiv e decomp osition similar to divide and c onquer metho ds. Spatial data structures are structures that manipulate spatial data, that is, data that has geometric coordinates. Spatial data structures refer to the organization of spatial data in a form suitable for digital computers. Lets look more in depth at the differences between raster and vector. Spatial data structures and acceleration algorithms. How does the computer see my vector and raster files.
In this paper we define the spatial data structure and discuss the manipulation of a spatial database for answering queries and for structural matching. Spatial data models and structures semantic scholar. A data structure is the logical view, and a file structure is the actual physical arrangement of the data. Spatial data model vector data model raster data model attribute data attribute aspatial information is the label name categorisation descriptiong associated with a spatial object the attributes can be as important as the spatial data themselves may be more complex than the spatial data may be a simple text label e. Data structures and intersection algorithms for 3d spatial. No matter what your interests are or what field you work in, spatial data is always being considered whether you know it or not. Suc h tec hniques are kno wn as spatial indexing metho ds. High spatial variability is efficiently represented only raster can store image data e. Analysis is an important part of gis which allows spatial operations with data e. Discrete soil, land use, cities continuous elevation or rain fall. Nonhierarchical data structures almost all data structures used in rendering of complex scenes are hierarchical in nature however, for some simpler cases, or for some special purpose situations such as gpu rendering, it is occasionally useful to have nonhierarchical data structures one possible example is a uniform grid. Hierarc hical data structures are based on the principle of.
Download slides as pdf 1 comment 2 comments 3 comments 3 comments 1 comment 1 comment. Spatial data models and data structures sciencedirect. The most common solution, and the one that we focus on in the rest of this chapter, is to use data structures that are based on spatial occupancy. Pdf the design and analysis of spatial data structures. Scribd is the worlds largest social reading and publishing site. Moreover, it contains kdtree implementations for nearestneighbor point queries, and utilities for distance computations in various metrics. Spatial data structures store data objects organized by position and are an important class of data structures used in geographic information systems, computer graphics, robotics, and many other. The design and analysis of spatial data structures. Different gis may contain information of value to the other, but. Fifth, those intersection algorithms that have been designed for 3d spatial objects require very tailormade internal data representations that are not suitable to implement other 3d operations. Spatial data structures 3 data structures to store geometric information sample applications collision detection location queries chemical simulations rendering spatial data structures for ray tracing objectcentric data structures bounding volumes space subdivision grids, octrees, bsp trees speedup of 10x, 100x. Choice of an optimal data structure depends on the. The focus is on hierarchical data structures, including a number of variants of quadtrees, which sort the data. Spatial data structures data structures to store geometric information sample applications height field representation collision detection hierarchical bounding volumes surgical simulations finite element method rendering spatial data structures for ray tracing objectcentric data structures bounding volumes.
Thus an understanding of spatial data structures is important in the study of geographic data management. This section presents two spatial data structures for storing point data in two or more dimensions. Traditionally, there are two broad methods used to store data in a gis for both abstractions. The data or information that identifies the geographic location of features and boundries. Spatial data structures carnegie mellon university. A printable pdf version of this project list is available here. Games, movie production rendering tools permitting faster realtime rendering, intersection testing, collision detection, ray tracing, global illumination.
Attribute data the information linked to the geographic features spatial data describing them data layers are the result of combining spatial and attribute data. In the raster world, we have grid cells representing real world features. University of freiburg institute of computer science computer graphics laboratory. Pdf the chapter focuses on the semantics of spatial concepts and their formalizations.
Lecture 1 intro to gis and gis vector and raster data models. Spatial data, as used in geographic information systems, gives rise to particular problems in deriving suitable data models and structures because of the diverse sources and applications of the data. One such data structure is the quadtree octree in three dimensions. The gis spatial data model university of washington. Spatial data can represent vector and raster data models realworld features that have discrete boundaries such as roads, buildings, lakes, rivers, administrative boundaries as well as realworld phenomenafeatures that have nondiscrete boundaries such as precipitation and nutrient levels, terrain. Spatial data structures answer questions like\who is near me\. Introduction to gis basics, data, analysis case studies. One of the strengths of the vector data model is that it can be used to render geographic features with great precision however, this comes at the cost of greater complexity in data structures, which sometimes translates to slow processing speed. In the vector world, we have points, lines and polygons that consist of vertices and paths. Implement the rtree data structure and the packed rtree data structure. Spatial data types provide the information that a computer requires to reconstruct the spatial data in digital form. Spatial subdivision basic idea data structures related approaches. Vector data structures represent geographic objects or phenomenon as distinct geometries with specific characteristics and may also include topology.
Cs6345 spatial data structures suggestions for term projects. Spatial data structuresspatial data structures data structures to store geometric information sample applications collision detection location queries chemical simulations rendering spatial data structures for ray tracing objectcentric data structures bounding volumes space subdivision grids, octrees, bsp. Can overlay displays easily can easily manipulate data table can have many variables linked to one geographic file better suited for map output a simple data structure. The state records administrator also provides direction and guidance on data release and fees. A framework is proposed consisting of spatial concepts. Pdf cosmic voids, spatial algorithms and data structures. Spatial indexing structures data structures to accelerate queries of the kind.
Spatial data structures umd department of computer science. Introduction to gis and spatial data vector and raster comparison vector raster compact data structure for homogenous areas. Spatial data models and spatial data structures this section focuses on the methods available for the actual implementation of geographic models within gis. Spatial data structures spatial data structures describe the rules that are used to represent geographic data in geographic information systems gis. Height field representation collision detection hierarchical bounding volumes surgical simulations finite element method rendering. Spatial data structures computer data algorithms and. Pdf highlevel spatial data structures for gis researchgate. There are a great number of spatial data structures, specific to either the raster or vector spatial data models, used by commercial gis. Spatial data structures free download as powerpoint presentation. Spatial data structures computer data algorithms and data. The design and analysis of spatial data structures aw.
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