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The ARC/INFO Coverage data structure (1981), a topological data model based on POLYVRT. Topology was a very early concern for GIS. The earliest vector systems, such as the Canadian Geographic Information System, did not manage topological relationships, and problems such as sliver polygons proliferated, especially in operations such as vector overlay. [9]
Some GIS software has tools for validating topological integrity rules (e.g. not allowing polygons to overlap or have gaps) on spaghetti data to prevent and/or correct topological errors. A hybrid topological data model has the option of storing topological relationship information as a separate layer built on top of a spaghetti data set.
In cartography, geology, and robotics, [1] a topological map is a type of diagram that has been simplified so that only vital information remains and unnecessary detail has been removed. These maps lack scale, also distance and direction are subject to change and/or variation, but the topological relationship between points is maintained.
Vector overlay is an operation (or class of operations) in a geographic information system (GIS) for integrating two or more vector spatial data sets. Terms such as polygon overlay, map overlay, and topological overlay are often used synonymously, although they are not identical in the range of operations they include.
The Dimensionally Extended 9-Intersection Model (DE-9IM) is a topological model and a standard used to describe the spatial relations of two regions (two geometries in two-dimensions, R 2), in geometry, point-set topology, geospatial topology, and fields related to computer spatial analysis.
A Topological relation is a qualitative relationship between two shapes that does not depend on a measurable space (that is, coordinates). Common examples of such predicates include "A is completely inside B," "A overlaps B," "A is adjacent to B" (i.e., sharing a boundary but no interior), and "A is disjoint from B" (not touching at all).
As the GIS industry grew to incorporate more casual users, the inherent complexity of the coverage data structure became a concern. When Esri released ArcView GIS 2.0 in 1992, it introduced the new shapefile format for vector data. This was a much simpler data model, eliminating features such as topology, but was still a georelational design.
In the future, a good way to follow should be to start a methodical project, based on the German Location map initiative, working continent after continent and country after country, to provide a complete set of SVG topographic maps, respecting these topographic conventions. To learn. Several tutorials are now available, on wiki-en, wiki-fr ...