Changes between Version 5 and Version 6 of WKTRaster/SeamlessArchitecture

Timestamp:

Jul 18, 2011, 1:28:52 PM (13 years ago)

Author:

bnordgren

Comment:

—

WKTRaster/SeamlessArchitecture

@@ -37 +37 @@
 Each individual association is represented by a <code>CV_GeometryValuePair</code>, or one of its children. Children of <code>CV_GeometryValuePair</code> set limits on the spatial information allowed, and specific coverage types (e.g., point coverages) are composed of associations formed by one of these children (e.g., <code>CV_PointValuePair</code>). The hierarchy is given in the following figure.
 
-[[Image:461]]
+[[Image(orig-gvp.png)]]
 
 This architecture does not require a full implementation of the entire hierarchy. Only two data types are required: <code>CV_GeometryValuePair</code> and <code>CV_GridPointValuePair</code>. The names of the implementing data types are unimportant, they must simply occupy the roles in the above diagram. Rigid adherence to the UML diagram would require that a <code>CV_DomainObject</code> be explicitly represented. This architecture specification allows the direct substitution of a geometry object for the cases where a temporal component is not part of the domain. If the domain is to include temporal information, however, a domain object with both a spatial and temporal component must be defined.
@@ -47 +47 @@
 A raster is more than a single association of spatial information to value information, yet less than a coverage. The raster data type is an aggregation of many individual associations which possess a gridded spatial structure. A georeferenced raster ties this gridded spatial structure to geolocations. A raster is, in short, a means of efficiently representing many values which are associated with many places. The following UML diagram shows the relevant constructs defined by ISO 19123.
 
-[[Image:462]]
+[[Image(grid.png)]]
 
 A <code>CV_Grid</code> by itself consists only of the metadata necessary to define a regular grid: number of dimensions, extent along each axis, and names for the axes. This constitutes basic header metadata only. There is no geospatial information at all. The data are also absent. All instances of <code>CV_Grid</code> may be related to certain other basic structures, as shown in the figure. However, the meaning of these structures and the extent to which they are populated with information, may vary depending on the information available.
@@ -61 +61 @@
 The basic top level schema for the coverage type is defined in the figure below. This builds on the tools provided previously and provides a common access mechanism which does not depend on the type of the underlying data.
 
-[[Image:463]]
+[[Image(coverage.png)]]
 
 Coverages add value over a simple collection of geometry-value pairs. They ensure that the collection of geometry-value pairs has a consistent value (e.g., values in the coverage have the same "type" everywhere). Three methods (<code>find</code>, <code>select</code>, and <code>list</code>) are shown on the Coverage type itself. Another method, an important method, is not shown on this diagram: <code>evaluate</code>.