From 219a2597201e36c8f1ce14fbd87b8434dd6e6022 Mon Sep 17 00:00:00 2001
From: ifv <ifv@opencascade.com>
Date: Mon, 20 Sep 2021 15:44:32 +0300
Subject: [PATCH] 0032569: Modeling Algorithm - Section not found

IntPatch/IntPatch_WLineTool.cxx - adding control of maximal ratio of distances between 3 sequential points.
---
 src/IntPatch/IntPatch_WLineTool.cxx | 47 ++++++++++++++++++++++++-----
 1 file changed, 40 insertions(+), 7 deletions(-)

diff --git a/src/IntPatch/IntPatch_WLineTool.cxx b/src/IntPatch/IntPatch_WLineTool.cxx
index d0730fbd53..17f2f572d8 100644
--- a/src/IntPatch/IntPatch_WLineTool.cxx
+++ b/src/IntPatch/IntPatch_WLineTool.cxx
@@ -390,6 +390,23 @@ static const Standard_Integer aNbSingleBezier = 30;
 // purpose  : Check and delete points using tube criteria.
 //            Static subfunction in ComputePurgedWLine.
 //=========================================================================
+static Standard_Boolean IsSurfPlaneLike(const Handle(Adaptor3d_HSurface)   &theS)
+{
+  if (theS->GetType() == GeomAbs_Plane)
+  {
+    return Standard_True;
+  }
+
+  if (theS->GetType() == GeomAbs_BSplineSurface)
+  {
+    if (theS->UDegree() == 1 && theS->VDegree() == 1)
+    {
+      return Standard_True;
+    }
+  }
+
+  return Standard_False;
+}
 static Handle(IntPatch_WLine)
   DeleteByTube(const Handle(IntPatch_WLine)       &theWLine,
                const Handle(Adaptor3d_HSurface)   &theS1,
@@ -419,6 +436,7 @@ static Handle(IntPatch_WLine)
   gp_Vec2d aBase2dVec2(UonS2[1] - UonS2[0], VonS2[1] - VonS2[0]);
   gp_Pnt   aBase3dPnt = theWLine->Point(1).Value();
   gp_Vec   aBase3dVec(theWLine->Point(1).Value(), theWLine->Point(2).Value());
+  Standard_Real aPrevStep = aBase3dVec.SquareMagnitude();
 
   // Choose base tolerance and scale it to pipe algorithm.
   const Standard_Real aBaseTolerance = Precision::Approximation();
@@ -431,6 +449,8 @@ static Handle(IntPatch_WLine)
   Standard_Real aTol3d = aBaseTolerance * aBaseTolerance;
 
   const Standard_Real aLimitCoeff = 0.99 * 0.99;
+  const Standard_Real aMaxSqrRatio = 15. * 15.;
+  Standard_Boolean isPlanePlane = IsSurfPlaneLike(theS1) && IsSurfPlaneLike(theS2);
   for(i = 3; i <= theWLine->NbPnts(); i++)
   {
     Standard_Boolean isDeleteState = Standard_False;
@@ -466,14 +486,27 @@ static Handle(IntPatch_WLine)
       if (Min(aStepOnS1, aStepOnS2) >= aLimitCoeff * Max(aStepOnS1, aStepOnS2))
       {
         // Set hash flag to "Delete" state.
-        isDeleteState = Standard_True;
-        aNewPointsHash.SetValue(i - 1, 1);
+        Standard_Real aCurrStep = aBase3dPnt.SquareDistance(aPnt3d);
+        Standard_Real aSqrRatio = 0.;
+        if (!isPlanePlane)
+        {
+          aSqrRatio = aPrevStep / aCurrStep;
+          if (aSqrRatio < 1.)
+          {
+            aSqrRatio = 1. / aSqrRatio;
+          }
+        }
+        if (aSqrRatio < aMaxSqrRatio)
+        {
+          isDeleteState = Standard_True;
+          aNewPointsHash.SetValue(i - 1, 1);
 
-        // Change middle point.
-        UonS1[1] = UonS1[2];
-        UonS2[1] = UonS2[2];
-        VonS1[1] = VonS1[2];
-        VonS2[1] = VonS2[2];
+          // Change middle point.
+          UonS1[1] = UonS1[2];
+          UonS2[1] = UonS2[2];
+          VonS1[1] = VonS1[2];
+          VonS2[1] = VonS2[2];
+        }
       }
     }