Wrong shape result imported from IGES file.

Hi All,

I have a IGES file. It contains a semi-sphere revolve face. It can be read correctly by other two softwares. But using occ6.3 and occ6.5.1, the result is very strange. Any idea? Thanks in advance.


toranzolorca's picture

Hello Cauchy Doing, the text below is from OCC 6.5.0 documentation (Data Exchange IGES FORMAT User's Guide), it explain the supported version to IGES format, please check the documentation of OCC 6.5.1 and the IGES version of your model.

IGES files up to and including IGES version 5.3 can be read. IGES files that are produced by
this interface conform to IGES version 5.3 (Initial Graphics Exchange Specification, IGES 5.3.
ANS US PRO/IPO-100-1996).
This manual principally deals with two Open CASCADE classes:
• The Reader class, which loads IGES files and translates their contents to Open
CASCADE shapes,
• The Writer class, which translates Open CASCADE shapes to IGES entities and
then writes these entities to IGES files.
File translation is performed in the programming mode, via C++ calls, and the resulting Open
CASCADE objects are shapes.
All definitions in IGES version 5.3 are recognized but only 3D geometric entities are
translated. When the processor encounters data, which is not translated, it ignores it and
writes a message identifying the types of data, which was not handled. This message can be
written either to a log file or to screen output.

Cauchy Ding's picture

Hi Gustavo,

Thank you for your reply. I am not sure why Catia, Hypermesh and Dynaform can read it and render it well. In fact, this revolve face is a sphere. I have tried to modify the raw face to render it similar as other softwares, but failed. Thank you all the same.


Forum supervisor's picture

Dear Cauchy Ding,
I would like to inform you that the posted problem has been checked and reproduced.
The corresponding issue with ID = 22888 has been registered.
Later you may check if the issue is resolved by checking references to the specified ID in OCCT Release Notes. The analysis of the issue will take some time depending on our technical capability and availability of resources.
You are also welcome to develop a corresponding patch and make a contribution via the Collaborative portal - http://dev.opencascade.org/index.php?q=home/get_involved.

Cauchy Ding's picture

Hi Supervisor,

Thank you.