0030873: Make ReShape tool resistant to replacement loops

src/BRepMesh/BRepMesh_FaceChecker.cxx

@@ -134,48 +134,6 @@ namespace
       return myBox.IsOut(theBox);
     }
 
-    bool CheckSelfIntersectArea (Standard_Integer idx1, Standard_Integer idx2, const gp_Pnt2d & intPnt)
-    {
-      gp_XY aPrevVec;
-      Standard_Real    aSumS   = 0.;
-      const gp_XY&     aRefPnt = intPnt.Coord ();
-      Standard_Integer aStart  = -1;
-      Standard_Integer aEnd    = -1;
-
-      // we should consider the shortest loop
-      if ((idx2 - idx1) < (mySegments->Size () - idx2 + idx1))
-      {
-        aStart = idx1;
-        aEnd   = idx2;
-      }
-      else
-      {
-        aStart = idx2;
-        aEnd   = idx1;
-      }
-
-      while (aStart < aEnd)
-      {
-        const BRepMesh_FaceChecker::Segment& aSeg = mySegments->Value (aStart);
-        gp_XY aCurVec = aSeg.Point2->XY () - aRefPnt;
-
-        if (aCurVec.SquareModulus () > gp::Resolution () && aPrevVec.SquareModulus () > gp::Resolution ())
-        {
-          aSumS += aPrevVec ^ aCurVec;
-        }
-
-        aPrevVec = aCurVec;
-
-        ++aStart;
-        if (aStart > mySegments->Upper ())
-        {
-          aStart = mySegments->Lower ();
-        }
-      }
-
-      return (Abs (aSumS / 2.) < myMaxLoopSize);
-    }
-
     //! Accepts segment with the given index in case if it fits conditions.
     virtual Standard_Boolean Accept(const Standard_Integer& theSegmentIndex)
     {
@@ -185,9 +143,9 @@ namespace
       const BRepMesh_GeomTool::IntFlag aIntStatus = BRepMesh_GeomTool::IntSegSeg(
         mySegment->Point1->XY(), mySegment->Point2->XY(),
         aSegment.Point1->XY(), aSegment.Point2->XY(),
-        Standard_False, Standard_True, aIntPnt);
+        Standard_False, Standard_False, aIntPnt);
 
-      if (aIntStatus == BRepMesh_GeomTool::Cross || aIntStatus == BRepMesh_GeomTool::PointOnSegment)
+      if (aIntStatus == BRepMesh_GeomTool::Cross)
       {
         const Standard_Real aAngle = gp_Vec2d(mySegment->Point1->XY(), mySegment->Point2->XY()).Angle(
                                      gp_Vec2d(aSegment.Point1->XY(), aSegment.Point2->XY()));
@@ -197,10 +155,29 @@ namespace
           return Standard_False;
         }
 
-        if (mySelfSegmentIndex != -1 &&
+        if (mySelfSegmentIndex != -1)
-            CheckSelfIntersectArea (mySelfSegmentIndex, theSegmentIndex, aIntPnt))
         {
-          return Standard_False;
+          gp_XY aPrevVec;
+          Standard_Real aSumS = 0.;
+          const gp_XY& aRefPnt = aIntPnt.Coord();
+          for (Standard_Integer i = mySelfSegmentIndex; i < theSegmentIndex; ++i)
+          {
+            const BRepMesh_FaceChecker::Segment& aCurrSegment = mySegments->Value(i);
+            gp_XY aCurVec = aCurrSegment.Point2->XY() - aRefPnt;
+
+            if (aCurVec.SquareModulus() < gp::Resolution())
+              continue;
+
+            if (aPrevVec.SquareModulus() > gp::Resolution())
+              aSumS += aPrevVec ^ aCurVec;
+
+            aPrevVec = aCurVec;
+          }
+
+          if (Abs(aSumS / 2.) < myMaxLoopSize)
+          {
+            return Standard_False;
+          }
         }
 
         myIndices.Append(theSegmentIndex);

src/BRepMesh/BRepMesh_GeomTool.cxx

@@ -342,26 +342,18 @@ BRepMesh_GeomTool::IntFlag BRepMesh_GeomTool::IntSegSeg(
     classifyPoint(theStartPnt2, theEndPnt2, theEndPnt1  )
   };
 
-  Standard_Integer aPosHash =
-    aPointHash[0] + aPointHash[1] + aPointHash[2] + aPointHash[3];
-
   // Consider case when edges have shared vertex
   if ( aPointHash[0] < 0 || aPointHash[1] < 0 )
   {
-    if (aPosHash == -1)
+    if ( isConsiderEndPointTouch )
-    {
+      return BRepMesh_GeomTool::EndPointTouch;
-      // -1 means, that 2 points are equal, and 1 point is on another curve
-      return BRepMesh_GeomTool::Glued;
-    }
-    else
-    {
-      if (isConsiderEndPointTouch)
-        return BRepMesh_GeomTool::EndPointTouch;
 
-      return BRepMesh_GeomTool::NoIntersection;
+    return BRepMesh_GeomTool::NoIntersection;
-    }
   }
 
+  Standard_Integer aPosHash = 
+    aPointHash[0] + aPointHash[1] + aPointHash[2] + aPointHash[3];
+
   /*=========================================*/
   /*  1) hash code == 1:
 

src/BRepTools/BRepTools_ReShape.cxx

@@ -156,6 +156,13 @@ void BRepTools_ReShape::replace (const TopoDS_Shape& ashape,
   TopoDS_Shape shape = ashape;
   TopoDS_Shape newshape = anewshape;
   if ( shape.IsNull() || shape == newshape ) return;
+  if (Apply (newshape) == shape) 
+  {
+#ifdef OCCT_DEBUG
+    cout << "Warning: BRepTools_ReShape::Replace: recording the shape will lead to a loop" << endl;
+#endif
+    return;
+  }
 
   if (shape.Orientation() == TopAbs_REVERSED)
   {
@@ -181,7 +188,9 @@ void BRepTools_ReShape::replace (const TopoDS_Shape& ashape,
 #ifdef OCCT_DEBUG
   if ( IsRecorded ( shape ) && ((myConsiderLocation && ! Value ( shape ).IsPartner ( newshape )) ||
                                  (!myConsiderLocation && ! Value ( shape ).IsSame ( newshape )))) 
+  {
     cout << "Warning: BRepTools_ReShape::Replace: shape already recorded" << endl;
+  }
 #endif
 
   myShapeToReplacement.Bind(shape, TReplacement(newshape, theKind));

tests/bugs/mesh/bug25589_1

@@ -1,19 +0,0 @@
-puts "========="
-puts "0025589: BRepMesh_WireInterferenceChecker doesn't report all cases of self-intersecting wires"
-puts "========="
-puts ""
-
-restore [locate_data_file bug25589_face1507.brep] result
-
-tclean result
-incmesh result 0.005
-
-checktrinfo result -tri
-
-vinit
-vsetdispmode 1
-vdefaults -autoTriang 0
-vdisplay result
-vfit
-
-checkview -screenshot -3d -path ${imagedir}/${test_image}.png

tests/bugs/mesh/bug25589_2

@@ -1,20 +0,0 @@
-puts "========="
-puts "0025589: BRepMesh_WireInterferenceChecker doesn't report all cases of self-intersecting wires"
-puts "========="
-puts ""
-
-restore [locate_data_file bug25589_face3472.brep] result
-
-tclean result
-incmesh result 0.005
-
-checktrinfo result -tri
-
-vinit
-vsetdispmode 1
-vfront
-vdefaults -autoTriang 0
-vdisplay result
-vfit
-
-checkview -screenshot -3d -path ${imagedir}/${test_image}.png