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Grid Shifts Files

Documentation | Other Specifications | Grid Shifts Files

The coordinate transformation engine can perform transformations using grid shift files.

Supported formats

  • NTv2 (.gsb)
    A standard file supported across many countries. It also includes information that is not in use (quality). Therefore, converting to a .ttkgs file is recommended.
  • NADCON files (.las, *.los, *.gtx)
    Not supported. Should be first converted to supported formats.
  • TatukGIS Grid Shift (.ttkgs)
    Minimized grid shift file format. Only for files deployed by TatukGIS.

How to deploy

  • Grid shit files are pretty quite big. Therefore, deploying all possible files is not a recommended option.
  • Copy desired files into the Datums subfolder of the application folder.
  • To provide general support for USA & Canada NAD27, deploy files:
    • conus
    • alaska
    • hawaii
    • prvi
    • stgeorge
    • stlrnc
    • stpaul
    • NTV2_0

Order of interpretation

A program will try to localize grid shift files in this order:

  1. File .gsb in application folder
  2. File .gsb in Datums subfolder,
  3. File .gsb in a folder specified by TGIS_CSTransformGridShift.Folder metadata.
  4. File .ttkgs files in application.
  5. File .ttkgs in Datums subfolder,
  6. File .ttkgs in a folder specified by TGIS_CSTransformGridShift.Folder metadata.

So, in short:

  1. File .gsb is more important than .ttkgs.
  2. File located in the application folder is more important than a file in some other location.

How to obtain grid shift files

We collect some common files for you. Files are installed in the deployment Grid Shift Files folder. The readme.txt file installed in the deployment folder contains information about grid shift files we are unable to provide or do not know where to find.

2019/10/02 15:08