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IGES interface

The IGES translator is a component of PHOENICS that translates an IGES format data file into the PHOENICS data format.

The file that IGES produces contains the geometry that is then used as the starting point for the normal PHOENICS procedure of building frames, grid matching and so on.

Configuring the IGES interface

It may occasionally be necessary to increase some array sizes if the IGES interface reports that the default size is too small, by making changes in the file iges.for.

The parameters that may need to be changed are:
UTOL User Defined Tolerance. Points closer together than this will be merged. If this value is negative then the tolerance stored in the IGES file is used.
NPOINT Number of points before paging occurs (limit is 26,000)
NLINE Number of lines before paging occurs (limit is 26,000)
NINTER Number of midline points before paging (limit is 26,000)
NDIR Number of directory entries before paging
NTRANS Number of transforms
IPSLIM Both i) The maximum number of sections on a parametric spline line + 1 and ii) Six times the number of knots in a NURB
NCOMP Composite curve data
NPMAX Maximum number of points on a PHOENICS line
NPLIN Number of points to be found on a B-spline line or Conic Arc; a negative value is used as a multiple of the number of definition points.
IEMAX Maximum number of subfigure instances

To build a modified IGES translator, with the above parameters changed:

  1. Go to the d_iges directory.
  2. Make the changes to the parameters.
  3. Compile iges.for. The command is either 'compile iges.for' or 'compf iges.for' depending on your hardware platform.
  4. Build the executable. The command is 'bldigs'.