TransLT SDK – DLL libraries for software developers


TransLT SDK is offered free of charge for software developers wishing to create applications that take advantage of the coordinates transformations capabilities of TransLT.

The libraries “TransLT.Win32.dll” and “TransLT.Win64.dll” can be used for coordinate transformations, drawing entities in Google Earth or saving them in files compatible for drawing in Google Earth.

The TransLT library offers the following functionalities:

  • The transformation of coordinates between two coordinates systems;
  • Drawing polygons, paths or points in Google Earth.

Supported coordinate operations:

  • coordinates conversions (including the use of a map projection);
  • transformations with parameters: 1D, 2D or 3D;
  • polynomial transformations;
  • coordinates offset using grid files;
  • coordinates offset;
  • transformations with own formulas.

For complete details about supported operations with coordinates, visit the „Supported Transformations and Conversions” page.

Coordinate transformation can be done based on a transformation model that is taken from a file, a model that contains operations with coordinates defined as transformation steps. If the transformation model supports the inverse calculation then the transformation can be done in reverse.

To create files with transformation models, we recommend that you use the main TransLT application where you can create and test transformation models. Also in the main application you can use the EPSG database to automatically create transformation steps. For this it is necessary to have a minimum of knowledge about coordinate reference systems (CRS) and about possible coordinate operations (CooOp) between these systems. Another important factor is the accuracy of the transformation that you need to know before making a new transformation model. It would be useful to have one or more points with coordinates in both systems to test the newly created model. If you can’t handle it, please write to us at, and if possible we will create the transformation model for you.

In the “Examples” folder you will find information about the implementation in Delphi and in Visual Studio, including the compiled executables. Also here you will find examples with some of the supported file types (transformation models, files with coordinates, files with graphic entities, etc.).

In the “Demo_TransLT_Library.exe” test application window you have exemplified how to make the settings in the “Language settings” and “Model properties” section and four usage examples in the sections: “Transformation test file”, “Test for one point”, “Test for entities file” and “Define entities, transform points and draw to Google Earth”.

Note on the choice of operating system 32bit or 64bit: For 32-bit operating systems TransLT.Win32.dll library operate with 80 bits (10 bytes) allocated to real numbers, about 19 to 20 significant digits and for 64-bit operating systems TransLT.Win64.dll library operate with 64 bits (8 bytes) allocated to real numbers, about 15 to 16 significant digits.