A Transformation can be defined as an mathematical operation which transforms some values into other values using a
specified function. In geographic terms this means, that some incoming coordinate in a specified crs, must be
transformed into a coordinate valid for some other crs. In general two different transformations can be distinguished:
- The helmert transformation allows coordinate transformation with a datum shift by going to euclidean
space and normalizing to WGS84
- Polynomial transformations use a polynomial to approximate a function which directly transforms coordinates
from one crs into another.
To accommodate these transformation the deegree crs package defines different transformation packages:
- {@link org.deegree.crs.transformations.coordinate coordinate}, which defines classes for chaining transformations (e.g. transformation steps). The resulting
concatenated transformation will define a function which transforms coordinates between two different coordinate
systems
- {@link org.deegree.crs.transformations.helmert helmert}, which transforms coordinates from one euclidean R^3 space into another
- {@link org.deegree.crs.transformations.polynomial polynomial}, which transforms coordinates direct between two different coordinate system using a polynomial
function
The TransformFactory tries to create the appropriate transformation(s) to maps coordinates from one coordinate
systems into another.
@author Rutger Bezema
@author last edited by: $Author: rbezema $
@version $Revision: 11234 $, $Date: 2007-03-20 10:15:15 +0100 (Di, 20 Mrz
2007)$