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Time as dimension, which treats time as another (3rd or 4th) spatial dimension, and using multidimensional vector or raster structures to create geometries incorporating time. Hägerstrand visualized his time geography this way, and some GIS models based on it use this approach. The NetCDF format supports managing temporal raster data as a ...
Raster data is stored in various formats; from a standard file-based structure of TIFF, JPEG, etc. to binary large object (BLOB) data stored directly in a relational database management system (RDBMS) similar to other vector-based feature classes. Database storage, when properly indexed, typically allows for quicker retrieval of the raster data ...
Data extraction is a GIS process similar to vector overlay, though it can be used in either vector or raster data analysis. Rather than combining the properties and features of both datasets, data extraction involves using a "clip" or "mask" to extract the features of one data set that fall within the spatial extent of another dataset.
The origin of the geodatabase was in the mid-1990s during the emergence of the first spatial databases.One early approach to integrating relational databases and GIS was the use of server middleware, a third-party program that stores the spatial data in database tables in a custom format, and translates it dynamically into a logical model that can be understood by the client software.
R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons. The R-tree was proposed by Antonin Guttman in 1984 [2] and has found significant use in both theoretical and applied contexts. [3]
There are also many different types of geodata, including vector files, raster files, geographic databases, web files, and multi-temporal data. Spatial data or spatial information is broader class of data whose geometry is relevant but it is not necessarily georeferenced , such as in computer-aided design (CAD), see geometric modeling .
A viewshed can be represented by raster data indicating the visibility of a viewpoint for or from an area of interest. In a binary representation, a cell (shown graphically as a pixel) with a value of 1 (or "true") indicates that the viewpoint is visible from that cell, while a value of 0 (false) indicates that the viewpoint is not visible.
ESRI's ArcGIS 8.3+ has the capability of rubbersheeting vector data, and ArcMap 9.2+ may also rubber-sheet raster layers.; Autodesk's AutoCAD Map 3D [1] and AutoCAD Civil 3D (which includes most of AutoCAD Map 3D's functionality) allows a user to rubbersheet vector data, and Autodesk's Raster Design (an add-in product for AutoCAD-based products) allows a user to rubbersheet raster data.