CoreandServices.book - Ocean - Schlumberger

Coordinate Systems
Coordinate Systems
Coordinates are the unit of measurement for spatial positioning data and are often listed
as ordered sets of three values. Probably the most common representations of coordinate
data are the grouping of X, Y, and Z values from a three-dimensional grid or the collection
of values representing Latitude, Longitude, and Elevation. Either of these represents a
grouping of values or data that pertains to a single reference called a Position. A
Coordinate System is a collection of coordinates that make up an entire known position
space with a single reference point. A position in this coordinate system is not an absolute
position but rather a relative, three-dimensional distance from this reference point. In
mathematics, this single reference point is called the "origin" of the coordinate system. In
Ocean we are primarily interested in converting a set of position data from one coordinate
system to another, which essentially involves translating each position within a source
coordinate system to its equivalent in the desired target coordinate system. Thus, a
coordinate system contains information to aid in the linear translation, linear scaling, and
angular rotation of input coordinates.
reference point
Fig. 4-16 Coordinate System Representation
position
A coordinate system engine allows applications to convert spatial data from one coordinate
to another. Ocean deploys Mentor's Coordinate System Library as its default coordinate
system engine.
Coordinate Systems Service
The Coordinate System Service, ICoordSysService, is the primary interface for
applications using coordinate systems and underlying coordinate system engines. It can
lookup a specific coordinate system by name or return a list of names of all coordinate
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