21.1 Description
The IGES tools provide a bidirectional translation between the Initial Graphics Exchange Specification and STEP IGES files. The iges2step tool reads an IGES file and writes a STEP IGES file. The step2iges tool reads a STEP IGES file and writes an IGES file.
21.2 Command Line (All Platforms)
iges2step [options] <iges_file>
step2iges [options] <step_file>
Both of these forms are wrappers that invoke the iges_cvt executable.
-nonulls- With this option, any empty or blank fields within the global or parameter data section of a STEP IGES file are replaced with the appropriate defaults.
-o <output_filename>- Use this option to specify output file name. Output is written with this name and the appropriate extension. Otherwise the input filename is used with the proper extension.
- The IGES tools retain only that part of a filename given to it up to, but not including the first `.' It then appends the proper extension when creating the output file.
-v- Verbose mode.
The STEP IGES file read and written by the IGES tools has an EXPRESS information model from STEP Tools, Inc. This model captures all of the information described by version 5.1 of IGES. The EXPRESS source file for this information model can be found in $ROSE/express/local/iges.exp .
These tools allow ST-Developer applications to mix IGES data with data described by other EXPRESS information models. For example, an IGES file can be used to describe the geometry of a product by making the IGESFile entity described in iges.exp one of the attributes of an entity in the product model.
The IGES tools can also be used to write programs that translate IGES data into the STEP AP Models.
21.3 Control Panel (Windows Only)
The IGES/STEP Converter Control Panel is shown in Figure 21.1. To use this tool, click IGES/STEP Converter in the ST-Developer Control Panel window. Specify the file(s) to convert, the output directory to place the converted files to, and select the direction of the conversion.
Click the OK button to convert the file(s).
If you wish to include multiple files in the process, you have to enclose each file name in double quotes, and separate the file names with spaces. If you use the browse [...] button and the Open File dialog this is done automatically.
Control Panel Options
IGES/STEP Converter Control Panel has the following elements.
File name(s)
Provides a space to type the name of the file(s) to convert. The [...] button displays the Open File dialog box that can be used to browse the file system and locate the file(s).
Output directory
Provides a space to type the name of the directory where the converted file(s) should be placed. If no output directory is specified, the converted file(s) will be placed in the same directory(ies) that the original file(s).
Direction
Select one of the directions to conver the files either from IGES to STEP or vice versa.
Verbose output
If selected, the tool produces a detailed report of its operation.
Replace nulls with defaults
This check box is available only when converting from STEP to IGES. Replace any empty or blank fields within the global or parameter data section of the STEP IGES file are replaced with the appropriate defaults. Equivalent to the -nonulls command-line option.
Option settings are saved in the system registry when you click the OK button, and will be reloaded from the registry next time you open the control panel. Settings are not saved if you click the Cancel button.
21.4 Examples
Example One -- To mix IGES data with other STEP data you can create an information model that references that IGES data. For example, the following information model uses IGES to describe the geometry of a part.
INCLUDE 'iges.exp';
SCHEMA Part;
REFERENCE FROM IGES
(IGESFile);
ENTITY Part_Geometry
name: STRING;
owner: STRING;
geometry: IGESFile;
END_ENTITY;
END_SCHEMA;
Example Two -- An IGES to STEP translator can be implemented by using the EXPRESS compiler to generate classes for the IGES schema in iges.exp . The output of the compiler will be a set of classes that can be used to read and write a STEP IGES file. Semantic translations to the STEP APs may then be implemented by adding methods to the classes. If the result is put into a program called iges2ap203 then a complete translation form IGES to AP203 can be implemented by typing the following command lines:
% iges2step -o a_step_file an_iges_file
# Following is not a STEP Tools, Inc product
% iges2ap203 -o an_ap203_file a_step_file