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Browse technical reports from the public and community areas of the former OCCT tracker. Public ticket numbers are retained; participant identities are anonymized.
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Community · OCCT:Shape Healing
Applying ShapeFix_Shape to the attached brep causes a crash. Setting aSfs.FixSolidMode() = false avoids this issue, maybe because this is a Moebius-type shape, but it should not cause a crash anyway. TopoDS_Shape shape ; BRep_Builder builder ; BRepTools::Read(shape, "Attachm
Community · OCCT:Modeling Data
Hello, With the attached brep, I get a volume of 329.6, but with CADAssistant I get a volume of 334.6. Why is there a difference please ? TopoDS_Shape lShape ; BRep_Builder lBuilder ; GProp_GProps lProperties ; BRepTools::Read(lShape, "Attachment 1 (BREP)", lBuilder) ;
Community · OCCT:Modeling Algorithms
Hello, The whole Attachment 1 (BREP) (see attached files) is considered as common part between Attachment 1 (BREP) and Attachment 7 (BREP) but that's clearly wrong (see attached picture) BRepAlgoAPI_Common lBuilder ; lBuilder.SetRunParallel(false) ; TopTools_ListOfShape lArgs ; T
Community · OCCT:Modeling Algorithms
Hi ! BRepAlgoAPI_Common can give no result although there is clearly a big common part between 2 shapes (see attached picture) You can use Tool and Argument joined in "NotAttachment 1 (ZIP)"
Community · OCCT:Modeling Algorithms
Hello, There are sometimes bad results in math_DirectPolynomialRoots::Solve(const Standard_Real a, const Standard_Real b, const Standard_Real c, const Standard_Real d, const Standard_Real e) We don't get the right results, with values: a=1.0000000000000004 b=-2.[revision removed]
Community · OCCT:Modeling Algorithms
Hello, The attached file is well seen on some CAD softwares, but import it with OCC gives a flat surface instead on a volume with 20 um of thickness. This code allows to scale the shape and see clearly the (bad) result : STEPControl_Reader reader ; reader.ReadFile("C:\\Attac
Community · OCCT:Modeling Algorithms
Hello, I try to use BRepAlgoAPI_Cut between 2 shapes. I should have a shape as result but I get an empty TopoDS_Shape. BRepAlgoAPI_Cut lBuilder ; BRep_Builder lBRepBuilder ; TopTools_ListOfShape lArgs ; TopoDS_Shape lArg, lTool ; BRepTools::Read(lArg, "Attachment 2 (BREP)&qu
Open CASCADE · OCCT:Modeling Algorithms
The class BRepClass3d_SolidExplorer has the field myBox, and it is computed during initialization of the class instance. But this property is never used in the current configuration. It is used only if preprocessor definition MARCHEPASSIUNESEULEFACE is defined in the file BRepCla
Community · OCCT:Modeling Algorithms
when a1 is not 0 and a2 is not 2 Pi and angle is not 2 Pi things go south: BRepPrimAPI_MakeTorus(axis, r1, r2, a1, a2, angle) Other combination of values may also be problematic. See discussion in forum. #include <iostream> #include <gp_Ax2.hxx> #include <TopoDS_Sh
Community · OCCT:Modeling Algorithms
IntPatch_InterferencePolyhedron is used in IntPatch_PrmPrmIntersection to compute two bi-parametrised surfaces intersection. In order to accelerate calculations use Bnd_BoundSortBox to collect intersect boxes. BRepExtrema_OverlapTool use BVH and get relatively fast speed. So I su
Community · OCCT:Modeling Algorithms
Bnd_Box have the same data and provide update function, and HLRAlgo_PolyData::Box only have data do not have update function, so there are many code about the box update. d
Community · OCCT:Modeling Algorithms
According to the Coons parametric equation(see the attach picture), the parameter U should used to evaluate the point on Coons patch, in the 7.2.0 source code, the parameter U is commented as follows: //gp_Pnt GeomFill_CoonsAlgPatch::Value(const Standard_Real U, gp_Pnt GeomFill_C
Community · OCCT:Modeling Algorithms
In file src/BRepLib/BRepLib.cxx, line 411: for (ii = 0 ; ii < 3 ; ii++ ) { should be changed to for (ii = 1 ; ii < 3 ; ii++ ) { Since ii == 0 always results in obtaining a null pointer Curve2dPtr after calling the first line BRep_Tool::CurveOnSurface (this function expects
Open CASCADE · OCCT:Mesh
The method BRepMesh_Delaun::isVertexInsidePolygon classifies a point inside 2D polygon calculating cumulative angle from the point to all segments. I found out that for a CCW polygon the angle computed by that procedure will be equal to -2PI. However, the final condition checks t
Open CASCADE · OCCT:Modeling Data
Usage of BRepTopAdaptor_SeqOfPtr leads to potential memory leaks (see 0031009). This issue proposes to get rid of BRepTopAdaptor_SeqOfPtr and substitute it by the collection of a certain type. Entities of this class are used in BRepTopAdaptor_FClass2d and IntTools_FClass2d. NA
Open CASCADE · OCCT:Documentation
OCCT team have new approach with reporting bug or features and questions. Bugs or features: Mantis: [archived tracker link removed] GH Issues: https://github.com/Open-Cascade-SAS/OCCT/issues GH Report issue: https://github.com/Open-Cascade-SAS/OCCT/issues/new/choose _ Question or
Use the current OCCT GitHub project for a new defect or improvement request.
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