From bae76f50db074e7629e46848aa69b13777d74f43 Mon Sep 17 00:00:00 2001
From: Pasukhin Dmitry <dpasukhi@opencascade.com>
Date: Sat, 25 Apr 2026 11:46:46 +0100
Subject: [PATCH] Modeling - Update function handling in
 GeomFill_ConstrainedFilling and GeomFill_CoonsAlgPatch (#922)

- Fixed a bug in GeomFill_ConstrainedFilling::Init(): law functions were
  discarded due to erroneous use of method Func() instead of SetFunc().
- Corrected parameter usage in GeomFill_CoonsAlgPatch::Value() to ensure
  proper variable assignment for curve evaluation.
---
 .../GeomFill/GeomFill_ConstrainedFilling.cxx           | 10 +++++-----
 .../TKGeomAlgo/GeomFill/GeomFill_CoonsAlgPatch.cxx     |  5 ++---
 .../TKGeomAlgo/IntPatch/IntPatch_PolyhedronBVH.cxx     |  9 ++-------
 3 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_ConstrainedFilling.cxx b/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_ConstrainedFilling.cxx
index 052e7717cd..6a5df3aab6 100644
--- a/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_ConstrainedFilling.cxx
+++ b/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_ConstrainedFilling.cxx
@@ -434,9 +434,9 @@ void GeomFill_ConstrainedFilling::Init(const occ::handle<GeomFill_Boundary>& B1,
       {
         occ::handle<Law_Function> fu1, fu2;
         ptch->Func(fu1, fu2);
-        fu1 = Law::MixBnd(occ::down_cast<Law_Linear>(fu1));
-        fu2 = Law::MixBnd(occ::down_cast<Law_Linear>(fu2));
-        ptch->Func(fu1, fu2);
+        const occ::handle<Law_Function> ffu1 = Law::MixBnd(occ::down_cast<Law_Linear>(fu1));
+        const occ::handle<Law_Function> ffu2 = Law::MixBnd(occ::down_cast<Law_Linear>(fu2));
+        ptch->SetFunc(ffu1, ffu2);
         break;
       }
     }
@@ -523,8 +523,8 @@ void GeomFill_ConstrainedFilling::Init(const occ::handle<GeomFill_Boundary>& B1,
       {
         occ::handle<Law_Function> fu1, fu2;
         ptch->Func(fu1, fu2);
-        occ::handle<Law_Function> ffu1 = Law::MixBnd(occ::down_cast<Law_Linear>(fu1));
-        occ::handle<Law_Function> ffu2 = Law::MixBnd(occ::down_cast<Law_Linear>(fu2));
+        const occ::handle<Law_Function> ffu1 = Law::MixBnd(occ::down_cast<Law_Linear>(fu1));
+        const occ::handle<Law_Function> ffu2 = Law::MixBnd(occ::down_cast<Law_Linear>(fu2));
         ptch->SetFunc(ffu1, ffu2);
         break;
       }
diff --git a/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_CoonsAlgPatch.cxx b/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_CoonsAlgPatch.cxx
index 5048b6ac2c..e3abbaab61 100644
--- a/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_CoonsAlgPatch.cxx
+++ b/src/ModelingAlgorithms/TKGeomAlgo/GeomFill/GeomFill_CoonsAlgPatch.cxx
@@ -82,12 +82,11 @@ void GeomFill_CoonsAlgPatch::Func(occ::handle<Law_Function>& f1,
 
 //=================================================================================================
 
-// gp_Pnt GeomFill_CoonsAlgPatch::Value(const double U,
-gp_Pnt GeomFill_CoonsAlgPatch::Value(const double, const double V) const
+gp_Pnt GeomFill_CoonsAlgPatch::Value(const double U, const double V) const
 {
   double a0, a1, a2, a3;
   a0 = a[0]->Value(V);
-  a1 = a[1]->Value(V);
+  a1 = a[1]->Value(U);
   a2 = 1. - a0;
   a3 = 1. - a1;
   gp_XYZ cor, cortemp;
diff --git a/src/ModelingAlgorithms/TKGeomAlgo/IntPatch/IntPatch_PolyhedronBVH.cxx b/src/ModelingAlgorithms/TKGeomAlgo/IntPatch/IntPatch_PolyhedronBVH.cxx
index d00b6f7d98..05304bd360 100644
--- a/src/ModelingAlgorithms/TKGeomAlgo/IntPatch/IntPatch_PolyhedronBVH.cxx
+++ b/src/ModelingAlgorithms/TKGeomAlgo/IntPatch/IntPatch_PolyhedronBVH.cxx
@@ -166,15 +166,10 @@ double IntPatch_PolyhedronBVH::Center(const int theIndex, const int theAxis) con
 
 void IntPatch_PolyhedronBVH::Swap(const int theIndex1, const int theIndex2)
 {
-  if (theIndex1 == theIndex2)
+  if (theIndex1 != theIndex2)
   {
-    return;
+    std::swap(myIndexMap.ChangeValue(theIndex1), myIndexMap.ChangeValue(theIndex2));
   }
-
-  // Swap indices in the mapping
-  const int aTmp = myIndexMap.Value(theIndex1);
-  myIndexMap.SetValue(theIndex1, myIndexMap.Value(theIndex2));
-  myIndexMap.SetValue(theIndex2, aTmp);
 }
 
 //==================================================================================================