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tdraddregion – Script command

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Add a specific region from a geometry in a Sentaurus TDR file into Lumerical. The added regions are either a polygon in 2D or planar solid in 3D. This command is only available on Linux.

Syntax  Description 
tdraddregion (“file_name”,”region_name”, options );

Adds the geometry region specified by region_name from the TDR file specified by file_name, with additional settings provided with struct options. This function does not return any data. The parameters are as follows:

  • file_name: A string pointing to the name of the TDR file.
  • region_name: A string specifying the region to add from the TDR file. The region name must follow the format geometryname:regionname, or geometryname/regionname, or geometryname:regionname:materialname, or geometryname/regionname/materialname where names are from the TDR file, as can be inspected by tdrinfo.

    Note: You can only add regions of type Solid2d and Solid3d to Lumerical (i.e. 2D and 3D MixedElement geometry type in the TDR terminology). Other types, such as Envelope (i.e. boundary element) or Rectilinear (i.e. tensor grid) are not supported.
  • options: A struct detailing specific options for the geometry import, possible fields are listed below.

The options possible in the optional struct are as follows

Syntax  Description 
material The material name to use for the added region. Must correspond to one of the materials in the Lumerical material database. If none is given, the script command uses the default material for simulation objects.
destination_cs

A string that specifies the destination coordinate system for the added region in Lumerical. The script automatically performs coordinate system transformation from the TDR file to the destination coordinate system. The type of coordinate system in the TDR file can be inspected with tdrinfo.

Allowed values are:

2D:

  • cs_2d_y_x (default)
  • cs_2d_y_x_lh
  • cs_2d_y_x_neg
  • cs_2d_x_y or cs_2d_sprocess

3D:

  • cs_3d_y_x_z_neg
  • cs_3d_y_x_z
  • cs_3d_y_z_neg_x_neg
  • cs_3d_z_y_x_neg (default)
  • cs_3d_x_y_z or cs_3d_sprocess

These coordinate system names specify how the x,y,z axis in Lumerical aligns with cs_3d_sprocess in 3D and cs_2d_sprocess in 2D, both of which are defined such that the x-axis points opposite from the growth direction.

For example:

  • cs_3d_z_y_x_neg: \(x_{lum}=z_{sprocess}, y_{lum}=y_{sprocess}, z_{lum}=-x_{sprocess}\)
  • cs_3d_y_z_neg_x_neg: \(x_{lum}=y_{sprocess}, y_{lum}=-z_{sprocess}, z_{lum}=-x_{sprocess}\)

If cs_3d_sprocess (i.e. cs_3d_x_y_z) is the TDR coordinate system and cs_3d_z_y_x_neg is chosen as the destination coordinate system the geometry in Lumerical will be oriented in the same way as in the TDR file.
coplanar_tolerance Relative tolerance to merge coplanar elements. The default value is 1e-6. Similar as in extractstructure.
smoothing_passes Only applies in 3D. An integer value specifying the number of Laplacian smoothing on the surface mesh prior to import, the max allowed value is 20. If this value is set to 0, smoothing is turned off. The default value is 0. Similar as in extractstructure.
smoothing_tolerance Sets the allowed angular difference between triangles around a vertex where the vertex can be moved. The default value is 0.001. Similar as in extractstructure.
allow_tesselation Only applies in 3D. A Boolean value that allows for re-triangulation of the facets when set to true. Similar as in extractstructure.

Example

# Add the region with the name Aluminum_1 from the geometry with the name geometry_0,from a test tdr file
opt_struct = struct;
opt_struct.material="Al (Aluminium) - CRC";
tdraddregion("test_file.tdr","geometry_0/Aluminum_1",opt_struct);

Wrapper functions

The Knowledge Base article Synopsys Sentaurus™ interoperability – import from and export to TDR files contains a set of wrapper functions and examples which is a more user-friendly method of using this built-in script command.

See Also

Synopsys Sentaurus™ interoperability – import from and export to TDR files, tdrinfo, tdrwritedataset, tdrimportdataset

Associated files

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