New Bug Report Form - Forum Open Cascade Technology

Robert Boehne
Tue, 08/08/2000 - 20:32

Forums:

I just took a look at the bug report form to find any unfixed bugs. No matter what I put in the form, nothing came up. Is there nothing in the database yet, or is there some trick to getting a listing of known bugs?

Guillaume Paran
Wed, 08/09/2000 - 13:17

The bug report form has been created for the community to report and research the OpenCascade bugs. It is a new application, so the database is for the moment empty. You can still report any OpenCascade bug, add some comments and attach files if necessary.

ruell magpayo
Mon, 04/03/2023 - 03:31

We are using STEP file to load Brep data,
The step file I use is this one
https://drive.google.com/file/d/1jJ2P1rKjKA_aRWFuT4zfQjCMzuWK5LFf/view?u...
I uploaded it on my Gdrive instead since the Bug report form does not allow STEP file upload.

Bug
using the open cascade method to extract the BSpline, returned Knots has lesser count than expected.
On the attached file, and selecting an edge for example, number of Poles (control points) are 56 but the number of Knots is only 28,
expected value is 60.

Steps of replication
1. Load the specified file above, the file have 40 edges in all
2. Select an edge, if loaded in sequence, select the 27th edge (zero based index)
3. Extract the B Spline curve
BRepAdaptor_Curve myCurve = BRepAdaptor_Curve(GetSelectedTopoDSEdge());
Handle(Geom_BSplineCurve) bspline = myCurve.BSpline();

int deg = bspline->Degree(); // degree 3
int num_knots = bspline->NbKnots(); // knots 28
int num_poles = bspline->NbPoles(); // poles 56

gkv311 n
Mon, 04/03/2023 - 10:03

If you'll take a look onto messages from STEP translator, you'll see that some surface has been modified - I guess by shape healing logic to fix some issue with it:

09:56 ...    Step File Reading : '/storage/emulated/0/Download/ExampleSweepFix.STEP'      ...    STEP File   Read    ...
            ... Step File loaded  ...
         10130 records (entities,sub-lists,scopes), 34463 parameters      ... Parameters prepared ...
            ...   Objects analysed  ...
        STEP Loading done : 4902 Entities
09:56 Count STEP Translator Warnings for 'ExampleSweepFix.STEP'
       -----    -----------
          18    W:(BOUNDED_SURFACE,B_SPLINE_SURFACE,B_SPLINE_SURFACE_WITH_KNOTS,GEOMETRIC_REPRESENTATION_ITEM,RATIONAL_B_SPLINE_SURFACE,REPRESENTATION_ITEM,SURFACE): Surface forced to be periodic
          Nb Total:18  for 1 items

ruell magpayo
Mon, 04/03/2023 - 10:22

Ok, so what does this mean? how can I extract the correct information properly?

Dmitrii Pasukhin
Mon, 04/03/2023 - 11:53

Hello,

You have acess to the original Step data model. You can iterate on model and get any data that you want.

There I explain some examples: how to get the id of entity in STEP file? - Forum Open Cascade Technology
Few documentatin: STEP Translator - Open CASCADE Technology Documentation

Best regards, Dmtrii.