0026426: Draft angle algorithm modifies input argument + the result of the operation have very large tolerance values

Test-case for issue #26426

src/BRepOffsetAPI/BRepOffsetAPI_DraftAngle.cxx

@@ -251,6 +251,23 @@ const TopTools_ListOfShape& BRepOffsetAPI_DraftAngle::Modified(const TopoDS_Shap
   return myGenerated;
 }
 
+//=======================================================================
+//function : ModifiedShape
+//purpose  : 
+//=======================================================================
+
+TopoDS_Shape BRepOffsetAPI_DraftAngle::ModifiedShape
+  (const TopoDS_Shape& S) const
+{
+  if(S.ShapeType() == TopAbs_VERTEX)
+  {
+    if(myVtxToReplace.IsBound(S))
+    {
+      return myVtxToReplace(S);
+    }
+  }
+  return myModifier.ModifiedShape(S);
+}
 
 //=======================================================================
 //function : Build
@@ -265,9 +282,8 @@ void BRepOffsetAPI_DraftAngle::Build()
   }
   else {
     DoModif(myInitialShape);
-    //BRepLib::SameParameter( myShape, 1.0e-7, Standard_True ); //patch
     CorrectWires();
-    BRepLib::SameParameter( myShape, 1.0e-7, Standard_True ); //patch
+    CorrectVertexTol();
   }
 }
 
@@ -872,3 +888,91 @@ void BRepOffsetAPI_DraftAngle::CorrectWires()
           }
         }
 }
+//=======================================================================
+//function : CorrectVertexTol
+//purpose  : 
+//=======================================================================
+
+void BRepOffsetAPI_DraftAngle::CorrectVertexTol()
+{
+  TopTools_MapOfShape anInitVertices, anInitEdges, aNewEdges;
+  TopExp_Explorer anExp(myInitialShape, TopAbs_EDGE);
+  for(; anExp.More(); anExp.Next())
+  {
+    anInitEdges.Add(anExp.Current());
+    TopoDS_Iterator anIter(anExp.Current());
+    for(; anIter.More(); anIter.Next())
+    {
+      anInitVertices.Add(anIter.Value());
+    }
+  }
+  //
+
+  BRep_Builder aBB;
+  myVtxToReplace.Clear();
+  anExp.Init(myShape, TopAbs_EDGE);
+  for(; anExp.More(); anExp.Next())
+  {
+    const TopoDS_Shape& anE = anExp.Current();
+    //Skip old (not modified) edges
+    if(anInitEdges.Contains(anE))
+      continue;
+    //
+    //Skip processed edges
+    if(aNewEdges.Contains(anE))
+      continue;
+    //
+    aNewEdges.Add(anE);
+    //
+    Standard_Real anETol = BRep_Tool::Tolerance(TopoDS::Edge(anE));
+    TopoDS_Iterator anIter(anE);
+    for(; anIter.More(); anIter.Next())
+    {
+      const TopoDS_Vertex& aVtx = TopoDS::Vertex(anIter.Value());
+      if(anInitVertices.Contains(aVtx))
+      {
+        if(myVtxToReplace.IsBound(aVtx))
+        {
+          aBB.UpdateVertex(TopoDS::Vertex(myVtxToReplace(aVtx)), anETol + Epsilon(anETol));
+        }
+        else
+        {
+          Standard_Real aVTol = BRep_Tool::Tolerance(aVtx);
+          if(aVTol < anETol)
+          {
+            TopoDS_Vertex aNewVtx;
+            gp_Pnt aVPnt = BRep_Tool::Pnt(aVtx);
+            aBB.MakeVertex(aNewVtx, aVPnt,anETol + Epsilon(anETol));
+            myVtxToReplace.Bind(aVtx, aNewVtx);
+          }
+        }
+      }
+      else
+      {
+        aBB.UpdateVertex(aVtx, anETol + Epsilon(anETol));
+      }
+    }
+  }
+  //
+  if(myVtxToReplace.IsEmpty())
+  {
+    return;
+  }
+  //
+  BRepTools_Substitution aSub;
+  TopTools_DataMapIteratorOfDataMapOfShapeShape anIter(myVtxToReplace);
+  for(; anIter.More(); anIter.Next())
+  {
+    TopTools_ListOfShape aSubVtx;
+    aSubVtx.Append(anIter.Value());
+    aSub.Substitute(anIter.Key(), aSubVtx);
+  }
+  aSub.Build( myShape );
+  if (aSub.IsCopied( myShape ))
+  {
+    const TopTools_ListOfShape& listSh = aSub.Copy( myShape );
+    if (! listSh.IsEmpty())
+      myShape = listSh.First();
+  }
+  //
+}

src/BRepOffsetAPI/BRepOffsetAPI_DraftAngle.hxx

@@ -22,6 +22,7 @@
 #include <Standard_Handle.hxx>
 
 #include <TopTools_ListOfShape.hxx>
+#include <TopTools_DataMapOfShapeShape.hxx>
 #include <BRepBuilderAPI_ModifyShape.hxx>
 #include <Standard_Real.hxx>
 #include <Standard_Boolean.hxx>
@@ -185,6 +186,14 @@ public:
   //! <S>.
   Standard_EXPORT virtual const TopTools_ListOfShape& Modified (const TopoDS_Shape& S) Standard_OVERRIDE;
 
+  //! Returns the modified shape corresponding to <S>.
+  //! S can correspond to the entire initial shape or to its subshape.
+  //! Raises exceptions
+  //! Standard_NoSuchObject if S is not the initial shape or
+  //! a subshape of the initial shape to which the
+  //! transformation has been applied. 
+  Standard_EXPORT virtual TopoDS_Shape ModifiedShape (const TopoDS_Shape& S) const Standard_OVERRIDE;
+
 
 
 
@@ -196,10 +205,9 @@ protected:
 
 private:
 
+  Standard_EXPORT void CorrectVertexTol();
 
-
+  TopTools_DataMapOfShapeShape myVtxToReplace;
-  TopTools_ListOfShape myModifiedShapes;
-
 
 };
 

src/Draft/Draft_Modification.cxx

@@ -54,13 +54,91 @@
 #include <TopoDS_Shape.hxx>
 #include <TopoDS_Vertex.hxx>
 #include <TopTools_ListIteratorOfListOfShape.hxx>
+#include <GeomLib_CheckCurveOnSurface.hxx>
+#include <BRepLib.hxx>
+//
+static Standard_Real EvalTol(const Handle(Geom_Curve)& C3d, 
+  const Handle(Geom2d_Curve) C2d, 
+  const Handle(Geom_Surface)& S,
+  const Standard_Real f,
+  const Standard_Real l)
+{
+  Standard_Real first = f, last = l;
+  //Set first, last to avoid ErrosStatus = 2 because of 
+  //too strong checking of limits in class CheckCurveOnSurface
+  //
+  if(!C3d->IsPeriodic())
+  {
+    first = Max(first, C3d->FirstParameter());
+    last = Min(last, C3d->LastParameter());
+  }
+  if(!C2d->IsPeriodic())
+  {
+    first = Max(first, C2d->FirstParameter());
+    last = Min(last, C2d->LastParameter());
+  }
+
+  GeomLib_CheckCurveOnSurface CT(C3d, S, first, last);
+  CT.Perform(C2d);
+  if(CT.IsDone())
+  {
+    return CT.MaxDistance();
+  }
+  else
+  {
+    if(CT.ErrorStatus() == 3 || (CT.ErrorStatus() == 2 &&
+      (C3d->IsPeriodic() || C2d->IsPeriodic())))
+    {
+      //Try to estimate by sample points
+      Standard_Integer nbint = 22;
+      Standard_Real dt = (last - first) / nbint;
+      dt = Max(dt, Precision::Confusion());
+      Standard_Real d, dmax = 0.;
+      gp_Pnt2d aP2d;
+      gp_Pnt aPC, aPS;
+      Standard_Integer cnt = 0; 
+      Standard_Real t = first;
+      for(; t <= last; t += dt)
+      {
+        cnt++;
+        C2d->D0(t, aP2d);
+        C3d->D0(t, aPC);
+        S->D0(aP2d.X(), aP2d.Y(), aPS);
+        d = aPS.SquareDistance(aPC);
+        if(d > dmax)
+        {
+          dmax = d;
+        }
+      }
+      if(cnt < nbint + 1)
+      {
+        t = last;
+        C2d->D0(t, aP2d);
+        C3d->D0(t, aPC);
+        S->D0(aP2d.X(), aP2d.Y(), aPS);
+        d = aPS.SquareDistance(aPC);
+        if(d > dmax)
+        {
+          dmax = d;
+        }
+      }
+
+      dmax = 1.2 * Sqrt(dmax);
+      return dmax;
+    }
+    else
+    {
+      return 0.;
+    }
+  }
+}
 
 //=======================================================================
 //function : Draft_Modification
 //purpose  : 
 //=======================================================================
 Draft_Modification::Draft_Modification (const TopoDS_Shape& S) :
-       myComp(Standard_False),myShape(S)
+myComp(Standard_False),myShape(S)
 {
   TopExp::MapShapesAndAncestors(myShape,TopAbs_EDGE,TopAbs_FACE,myEFMap);
 }
@@ -381,6 +459,8 @@ Standard_Boolean Draft_Modification::NewCurve2d(const TopoDS_Edge& E,
 
   Handle(Geom_Surface) SB = myFMap.FindFromKey(F).Geometry();
 
+  Tol = BRep_Tool::Tolerance(E);
+
   const Draft_EdgeInfo& Einf = myEMap.FindFromKey(E);
   if ( Einf.FirstFace().IsSame(F) && !Einf.FirstPC().IsNull()) {
     C = Einf.FirstPC();
@@ -398,8 +478,6 @@ Standard_Boolean Draft_Modification::NewCurve2d(const TopoDS_Edge& E,
       }
     }
 
-    Tol = BRep_Tool::Tolerance(E);
-    
     //  if (!BRep_Tool::IsClosed(E,F)) {
     BRep_Tool::Range(NewE,Fp,Lp);
     Handle(Geom_TrimmedCurve) TC = new Geom_TrimmedCurve(myEMap.FindFromKey(E).Geometry(),
@@ -459,6 +537,15 @@ Standard_Boolean Draft_Modification::NewCurve2d(const TopoDS_Edge& E,
       C->Translate(aV2DT);
     }
   }
+  //
+  Handle(Geom_Curve) aC3d = BRep_Tool::Curve(NewE, Fp, Lp);
+  Standard_Real newtol = EvalTol(aC3d, C, SB, Fp, Lp);
+  if(newtol > Tol)
+  {
+    Tol = newtol;
+    BRep_Builder B;
+    B.UpdateEdge(NewE, newtol);
+  }
   return Standard_True;
 }
 

src/Draft/Draft_Modification_1.cxx

@@ -1508,6 +1508,7 @@ void Draft_Modification::Perform ()
 
       for (Vinf.InitEdgeIterator();Vinf.MoreEdge(); Vinf.NextEdge()) {
         const TopoDS_Edge& Edg = Vinf.Edge();
+        Standard_Real initpar = Vinf.Parameter(Edg);
         //const Draft_EdgeInfo& Einf = myEMap(Edg);
         Draft_EdgeInfo& Einf = myEMap.ChangeFromKey(Edg);
         //Vinf.ChangeParameter(Edg) = Parameter(Einf.Geometry(),pvt);
@@ -1520,10 +1521,22 @@ void Draft_Modification::Perform ()
           Vinf.ChangeParameter(Edg) = SmartParameter( Einf, BRep_Tool::Tolerance(Edg), pvt, done, S1, S2 );
         }
         else
+        {
+          if(Abs(initpar - param) > Precision::PConfusion())
+          {
+            Standard_Real f, l;
+            TopLoc_Location Loc;
+            const Handle(Geom_Curve)& aC = BRep_Tool::Curve(Edg, Loc, f, l);
+            if(aC->DynamicType() == STANDARD_TYPE(Geom_TrimmedCurve))
+            {
+              Einf.SetNewGeometry(Standard_True);
+            }
+          }
           Vinf.ChangeParameter(Edg) = param;
         }
       }
     }
+  }
 
   // small loop of validation/protection
 

tests/bugs/modalg_6/bug26426

@@ -0,0 +1,32 @@
+puts "========"
+puts "OCC26426"
+puts "========"
+puts ""
+################################################################################################################
+# Draft angle algorithm modifies input argument + the result of the operation have very large tolerance values
+################################################################################################################
+
+restore [locate_data_file OCC26426-prism_shape.brep] b
+
+set bug_info_0 [tolerance b]
+set bug_info_0 [lindex $bug_info_0 1]
+set bug_info_0 [string trim [string range $bug_info_0 [expr {[string first "=" $bug_info_0] + 1}] [expr {[string length $bug_info_0] - 1}]]]
+
+explode b f
+depouille r b 0 0 -1 b_1 -10 0 0 -40 0 0 1
+
+set bug_info_1 [tolerance b]
+set bug_info_1 [lindex $bug_info_1 1]
+set bug_info_1 [string trim [string range $bug_info_1 [expr {[string first "=" $bug_info_1] + 1}] [expr {[string length $bug_info_1] - 1}]]]
+
+set bug_info_2 [tolerance r]
+set bug_info_2 [lindex $bug_info_2 1]
+set bug_info_2 [string trim [string range $bug_info_2 [expr {[string first "=" $bug_info_2] + 1}] [expr {[string length $bug_info_2] - 1}]]]
+
+if {$bug_info_0 < $bug_info_1} {
+  puts "ERROR: OCC26426 is reproduced. Tolerance has been increased (case 1)."
+}
+
+if {[expr {$bug_info_0 + 0.0000001}] < $bug_info_2} {
+  puts "ERROR: OCC26426 is reproduced. Tolerance has been increased (case 2)."
+}

tests/draft/angle/G2

@@ -1,5 +1,7 @@
 #E6----------------------------------------------
-puts "TODO OCC22803 ALL: Faulty shapes in variables faulty_1 to faulty_"
+#puts "TODO OCC22803 ALL: Faulty shapes in variables faulty_1 to faulty_"
+puts "TODO OCC26426 ALL: Error: The tolerance of the resulting shape is too big "
+
 
 ptorus pt 25 24 90
 profile pr o 20 18 5  p 0 -1 0 1 0 0 l 10 t 0 30 \

tests/draft/angle/K5

@@ -1,5 +1,5 @@
 #C5----------------------------------------------
-puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_6"
+puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_"
 
 plane ps 10 -3 0  1 0 0  0 .2 1
 psphere ps ps 20

tests/draft/angle/K7

@@ -1,5 +1,5 @@
 #D3---------------------------------------------
-puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_6"
+puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_"
 puts "TODO OCC22803 Linux Windows: Error : The area of the resulting shape is"
 
 plane pt 0 0 0 1 0 0

tests/draft/angle/M2

@@ -1,8 +1,9 @@
 # Original bug : pro12877
 # Date : 02 Dec 98
 
-puts "TODO OCC22803 All: Error: The tolerance of the resulting shape is too big"
+#puts "TODO OCC22803 All: Error: The tolerance of the resulting shape is too big"
 #puts "TODO OCC23511 Linux: The area of the resulting shape is 186543"
+puts "TODO OCC26426 All: Faulty shapes in variables faulty_1 to faulty_"
 
 restore [locate_data_file CFE903_pro12ggx.rle] base
 

tests/draft/angle/M4

@@ -1,7 +1,7 @@
 # Original bug : pro16449
 # Date : 18 Dec 98
 
-puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_4"
+puts "TODO OCC22803 All:Faulty shapes in variables faulty_1 to faulty_"
 
 restore [locate_data_file CFE903_pro16gha.rle] base