View Issue Details

IDProjectCategoryView StatusLast Update
0022715CommunityOCCT:Data Exchangepublic2013-04-29 15:21
Reporterszy Assigned Toika 
Status closedResolutionfixed 
Product Version6.5.1 
Target Version6.6.0Fixed in Version6.6.0 
Summary0022715: Incorrect faces of the filleted cube after import from iges file
DescriptionPost from the Forum -

"It is a cube with fillets, constant fillets, same radiuses everywhere.
When I load the data into Draw, I see problems in IGES. It looks like the cylinders are not treated properly (in this case).
STEP format works fine.

I can workaround the problem if I convert to nurbs the cylinders in the original CAD format before saving in IGES. I would say that it is an obvious workaround but it would be much better if we could treat the (trimmed) cylinders within IGES format.

Can anyone make a test and verify it?
Is there any hidden IGES param that I have to activate before loading my file?
Markus Rhein | reply 2011/08/24 17:45
Hello Davide,

I can confirm with Win 64 Bit, OCC 6.5.0 and standard import parameters there are missing faces after IGES import. The import works correct if you set the read.surfacecurve.mode parameter to the value 3 or -3:


This parameter is described in the IGES format user guide. I also have the problem with some IGES files, that the default parameter for this won╢t work and I have to set the import parameter manually to a certain value to enforce usage of 2D or 3D curves respectively. Does anyone know: Is there a automatic way to determine witch parameter should be used?

Zip file is attached.
Import as from step as from iges has 26 faces in the resulting shape.
But when importing from iges file the cylindrical faces are more narrow comparing with analogical faces from step file. It looks like these faces lost half area.
Steps To Reproducepload All
readstep cube.stp s * ; ## resulting shape s_1 is OK
whatis s_1 ; ## SOLID
explo s_1 F ; ## => 26 faces
readiges cube.igs s2 *; ## resulting shape is KO
whatis s2 ; ## COMPOUND
explo s2 F; ## 26 faces, but first 12 faces (s2_1,..., s2_12 - are wrong)
explo s2
TagsNo tags attached.
Test case numberbugs iges bug22715_1, bug22715_2

Attached Files

  • cube.7z (72,120 bytes)
  • bug22715_1 (849 bytes)
  • bug22715_2 (860 bytes)


related to 0023018 closedika Open CASCADE incorrectly writes/reads IGES Tabulated Cylinders (Type 122) 



2011-08-25 10:37


cube.7z (72,120 bytes)


2012-12-06 15:26

developer   ~0022592

Parametrization of tabulated cylinders was changed(in writing and reading) in accordance of Type122 to [0,1]x[0,1]

Git branch CR22715 is ready to be reviewed.

Dear GKA,
PLease review.


2012-12-06 18:12

developer   ~0022601

Dear bugmaster.

Branch CR22715 is ready to be tested


2012-12-24 18:02


bug22715_1 (849 bytes)


2012-12-24 18:02


bug22715_2 (860 bytes)


2012-12-24 18:04

tester   ~0022818

Dear BugMaster,

Branch CR22715 (and products from GIT master) was compiled on Linux and
Windows platforms and tested.

Not detected

Not detected

Testing cases:
bugs iges bug22715_1, bug22715_2 - OK.

Related Changesets

occt: master a9da59ff

2012-12-28 13:59:09


Details Diff
0022715: Incorrect faces of the filleted cube after import from iges file

Writing and reading tabulated cylinders in IGES were changed in accordance of Type 122 (parametrization [0,1]x[0,1]

some cosmetic changes
Adding test cases for this fix
Affected Issues
mod - src/BRepToIGES/BRepToIGES_BRWire.cxx Diff File
mod - src/IGESToBRep/IGESToBRep_TopoSurface.cxx Diff File
add - tests/bugs/iges/bug22715_1 Diff File
add - tests/bugs/iges/bug22715_2 Diff File

Issue History

Date Modified Username Field Change
2011-08-25 10:37 szy New Issue
2011-08-25 10:37 szy Assigned To => bugmaster
2011-08-25 10:37 szy File Added: cube.7z
2011-09-21 11:12 bugmaster Target Version 6.5.2 => 6.5.3
2011-09-21 14:00 szy Assigned To bugmaster => gka
2011-09-21 14:00 szy Status new => assigned
2012-02-09 08:53 abv Target Version 6.5.3 => 6.5.4
2012-10-19 17:18 gka Target Version 6.5.4 => 6.6.0
2012-10-19 17:19 gka Assigned To gka => omy
2012-10-26 20:31 abv Assigned To omy => ika
2012-11-22 11:11 abv Relationship added related to 0023018
2012-12-06 15:26 ika Note Added: 0022592
2012-12-06 15:26 ika Assigned To ika => gka
2012-12-06 15:26 ika Status assigned => resolved
2012-12-06 18:12 gka Note Added: 0022601
2012-12-06 18:12 gka Status resolved => reviewed
2012-12-06 20:20 mkv Assigned To gka => mkv
2012-12-24 18:02 mkv File Added: bug22715_1
2012-12-24 18:02 mkv File Added: bug22715_2
2012-12-24 18:04 mkv Note Added: 0022818
2012-12-24 18:05 mkv Test case number => bugs iges bug22715_1, bug22715_2
2012-12-24 18:05 mkv Assigned To mkv => bugmaster
2012-12-24 18:05 mkv Status reviewed => tested
2013-01-04 11:35 ika Changeset attached => occt master a9da59ff
2013-01-04 11:35 ika Assigned To bugmaster => ika
2013-01-04 11:35 ika Status tested => verified
2013-01-04 11:35 ika Resolution open => fixed
2013-04-23 13:36 aiv Status verified => closed
2013-04-29 15:21 aiv Fixed in Version => 6.6.0