IDfsProjection Interface

You can use the

DHI.Projections

The WKTString is a WKT string for a spatial reference system. A number of abbreviated strings also exists, i.e., "UTM-33" for a WGS-84 UTM zone 33 projection, and "LONG/LAT" for WGS-84 geographical coordinates.

There are 3 levels of coordinates: Geographical coordinates (longitude, latitude) in degrees, projection coordinates (easting, northing), and model/user defined coordinates (x,y).

All coordinates in a dfs file are stored in model coordinates.

The WKTString defines which ellipsoid the geographical coordinates use (example: WGS-84).

The WKTString defines the mapping from geographical coordinates to projection coordinates.

The Longitude, Latitude and Orientation defines the origin and the orientation of the model coordinates. It is used to move and rotate the model coordinates, i.e., a dfs2 file with a 2D equidistant axis defines its model coordinate origin and orientation here (and not in its axis definition, though that would also be possible).

See Orientation for the definition of the orientation. The model coordinates are rotated around its origin.

If Orientation is zero, and Longitude and Latitude matches the origin of the projection coordinate system, then projection coordinates equals model coordinates. Example: UTM-31 has projection origin at (lon,lat) = (3,0).