Data Exchange, IGES Export - Missing Model Curves in transfer cache

Dear Commenter 3 thank you for your. It is very helpful.
I will process your bug in the next week. But at least I will try to do that.
In case, if there will be no any notes or news, please send a new note to remind.

I found a possible more clear fix, let me check and process it :)
If you would like to became a contributor, please check https://dev.opencascade.org/content/occt-github-new-way-collaborate

Commenter 3 but to prepare more correct fix, could you please share file sample?
And prepared test case :)

Thank you for the prompt response!

Unfortunately getting the CLA signed by my employer is too much of a hassle for me to become a contributor.

I'm not sure what sample file you would like me to share? The problem is with the export (I believe the import is ok). I provided the attached Attachment 2 (CPP) file that reproduces the problem. Could you be more specific about what you would like? I also, unfortunately, am not familiar with the testing framework used by OCC to provide a test case... I regularly use other unit testing frameworks.

I'd be glad to test out your clearer fix.

Thank you, sorry, i didn't check the cpp file.
I thought that that filed contained fix. But it is a sample to reproduce. That even more helpful.

I should point out that what I put together was minimal to demonstrate this specific problem. I think a more rigorous test would be to loop over all the sub-shapes and make sure they are found in the cache.

Please let me know if I can help in any other way.

Commenter 4 I was curious if you had an update on the cleaner fix for this bug? I believe your first message asked me to ping you around this time.

@galbrams thank you.
Yes, I was asking to ping me. My apologies, there is no update for now. I will try to prepare changes in ongoing days.

Branch [archived branch] has been created by Commenter 2.

[revision removed]


Detailed log of new commits:

Author: Commenter 2
Date: Tue Sep 10 18:15:18 2024 +0000

    0033765: Data Exchange, IGES Export - Missing Model Curves in transfer cache
    
    Curve list should be not unique, list is recommended.
    One curve can be used by multiple edges.

Branch [archived branch] has been deleted by Participant.

[revision removed]

This bug has reappeared with the latest OCCT 7.9.0 release. The bug seems to be resolved by simply changing:
```
Standard_Integer BRepToIGESBRep_Entity::AddEdge(const TopoDS_Edge& myedge,
                                                const Handle(IGESData_IGESEntity)& mycurve3d)
{
  if (myedge.IsNull())
    return 0;

  const TopoDS_Shape& E = myedge;
  Handle(IGESData_IGESEntity) C = mycurve3d;
  Standard_Integer index = myEdges.FindIndex(E);
  if (index == 0)
  {
    index = myEdges.Add(E);
    myCurves.Append(C);
  }

  return index;
}
```
to the version below that fixes the problem:
```
Standard_Integer BRepToIGESBRep_Entity::AddEdge(const TopoDS_Edge& myedge,
                                                const Handle(IGESData_IGESEntity)& mycurve3d)
{
  if (myedge.IsNull())
    return 0;

  const TopoDS_Shape& E = myedge;
  Handle(IGESData_IGESEntity) C = mycurve3d;
  Standard_Integer index = myEdges.FindIndex(E);
  if (index == 0)
  {
    index = myEdges.Add(E);
    myCurves.Append(C);
  } else {
    myCurves.ChangeValue(index) = C;
  }

  return index;
}
```

Dear Author.
Thank you for your research. I need to validate the problem logic, replacing is not safe operation. Needs to check what happened.

Migrated bug: https://github.com/Open-Cascade-SAS/OCCT/issues/428

You should be able to compile and run the attached Attachment 2 (CPP) to check if the fix.