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The SEDRIS Data Representation Model
APPENDIX A - Classes Spatial Extent |
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An instance of this DRM class specifies the spatial extent of the containing object.
The spatial extent of an <Environment Root> instance within a transmittal, defined by the minimum and maximum latitude and longitude values (that is, the southwest and northeast corners).
The bounding parallelepiped of a <Model> instance representing a building, in LSR coordinates.
This class provides ISO 19115-compliant metadata that describes the location and spatial extent of a high-level SEDRIS object (such as, <Transmittal Root>, <Model>, <Image>.) <Spatial Extent> allows potential users of a SEDRIS transmittal to evaluate the region contained by the transmittal without necessarily having to actually obtain or examine the transmittal itself.
The spatial extent of an object is a simple bounding rectangle or parallelepiped that includes all the <Location> instances contained within that object. The bounding rectangle or parallelepiped is defined by two coordinate locations: the "minimum" corner, and the "maximum" corner, which represent the minimum and maximum values, respectively, along each of the axes of the spatial reference frame within which the object is defined.
The first <Location> component is the "minimum" corner, that is, the southwest corner. In the case of a 3D <Spatial Extent> instance, the z / elevation value of this <Location> component is the minimum elevation of the bounding volume being specified, rather than the elevation at the southwest corner. The second <Location> component is the "maximum" corner, that is, the northeast corner. In the case of a 3D <Spatial Extent> instance, the z / elevation value of this <Location> component is the maximum elevation of the bounding volume being specified, rather than the elevation at the northeast corner.
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