Coordinate Systems

Modern geospatial data are defined in numerous coordinate systems from around the world, which can complicate the process of combining them into a single view. A typical example involves converting government data (in latitude/longitude coordinates) to the working coordinate system of your project; another is converting historic data on an old geodetic datum to a modern geocentric datum.

The application’s Coordinate System Conversion options support virtually any pair of coordinate systems. Most conversions are between recognised coordinate systems, and the application uses the EPSG (European Petroleum Survey Group) database to supply the parameters for well over 5000 coordinate systems and their conversions. The application also supports the high-precision distortion grid methods (also known as shift or difference grids) required by modern datums.

The process takes place in two stages:

  1. Define the conversion by choosing the origin (From) and destination (To) coordinate systems. This happens only once, and typically takes just a few seconds.
  2. Use it to convert your coordinates.

Once the conversion is defined, you can convert DATA (and related) files, wireframes, interactively via the relevant options on the Survey tab, in the Coordinate Systems group. This setup-once, use-many-times philosophy hides the conversion details and ensures that you always use the same parameters every time you run that conversion.

  • On the Survey tab, in the Coordinate Systems group: Click New to define a new coordinate conversion. There are three ways to choose the From and To coordinate systems, which you can mix and match as required.

  • On the Survey tab, in the Coordinate Systems group: Click Convert (Keyboard) to use the keyboard to enter the calculation parameters for a coordinates conversion.

  • On the Survey tab, in the Coordinate Systems group: Click Convert (File) to convert coordinates in a Micromine DATA (and related) file.

  • On the Survey tab, in the Coordinate Systems group: Click Convert (Wireframe) to convert the coordinates in an input wireframe and optionally write the results to a second wireframe.

  • On the Survey tab, in the Coordinate Systems group: Click Plane Grids, to specify grid conversion parameters for two sets of 3D points with a known correspondence. A Least-Squares method is used to find the optimal rotation and translation between the two sets of points.