KratosMultiphysics · Igarizza · Nov 24, 2025
diff --git a/applications/OptimizationApplication/custom_python/add_custom_filters_to_python.cpp b/applications/OptimizationApplication/custom_python/add_custom_filters_to_python.cpp
@@ -39,7 +39,7 @@ void AddExplicitFilterUtils(
     namespace py = pybind11;
 
     py::class_<ExplicitFilterUtils<TContainerType>, typename ExplicitFilterUtils<TContainerType>::Pointer>(m, rName.c_str())
-        .def(py::init<const ModelPart&, const std::string&, const std::size_t, const std::size_t>(), py::arg("model_part"), py::arg("kernel_function_type"), py::arg("max_number_of_neighbours"), py::arg("echo_level"))
+        .def(py::init<const ModelPart&, const std::string&, const std::size_t, const std::size_t, bool>(), py::arg("model_part"), py::arg("kernel_function_type"), py::arg("max_number_of_neighbours"), py::arg("echo_level"), py::arg("node_cloud_mesh") = false)
         .def("SetRadius", &ExplicitFilterUtils<TContainerType>::SetRadius, py::arg("filter_radius"))
         .def("SetDamping", &ExplicitFilterUtils<TContainerType>::SetDamping, py::arg("damping"))
         .def("ForwardFilterField", &ExplicitFilterUtils<TContainerType>::ForwardFilterField, py::arg("mesh_independent_control_space_field"))

diff --git a/applications/OptimizationApplication/custom_utilities/filtering/explicit_filter_utils.cpp b/applications/OptimizationApplication/custom_utilities/filtering/explicit_filter_utils.cpp
@@ -68,17 +68,27 @@ Expression::ConstPointer GetNodalDomainSizeExpression(
 template<class TEntityType>
 double GetDomainSize(
     const EntityPoint<TEntityType>& rPoint,
-    Expression const * const pExpression)
+    Expression const * const pExpression,
+    const bool NodeCloudMesh)
 {
+    if (NodeCloudMesh == true){
+        KRATOS_ERROR << "NodeCloudMesh == true can be used only with ModelPart::NodeType." << std::endl;
+    }
     return rPoint.GetEntity().GetGeometry().DomainSize();
 }
 
 template<>
 double GetDomainSize(
     const EntityPoint<ModelPart::NodeType>& rPoint,
-    Expression const * const pExpression)
+    Expression const * const pExpression,
+    const bool NodeCloudMesh)
 {
-    return pExpression->Evaluate(rPoint.Id(), rPoint.Id(), 0);
+    if (NodeCloudMesh == true){
+        return 1.0;
+    }
+    else{
+        return pExpression->Evaluate(rPoint.Id(), rPoint.Id(), 0);
+    }
 }
 
 struct MeshIndependentType
@@ -111,10 +121,11 @@ void ComputeWeightForAllNeighbors(
     const std::vector<typename EntityPoint<TEntityType>::Pointer>& rNeighbourNodes,
     const std::vector<double>& rSquaredDistances,
     const IndexType NumberOfNeighbours,
-    Expression const * const pExpression)
+    Expression const * const pExpression,
+    const bool NodeCloudMesh)
 {
     for (IndexType i = 0; i < NumberOfNeighbours; ++i) {
-        const double domain_size = GetDomainSize(*rNeighbourNodes[i], pExpression);
+        const double domain_size = GetDomainSize(*rNeighbourNodes[i], pExpression, NodeCloudMesh);
         const double filter_weight = rFilterFunction.ComputeWeight(Radius, std::sqrt(rSquaredDistances[i])) * domain_size;
         rListOfWeights[i] = filter_weight;
         rSumOfWeights += filter_weight;
@@ -128,10 +139,12 @@ ExplicitFilterUtils<TContainerType>::ExplicitFilterUtils(
     const ModelPart& rModelPart,
     const std::string& rKernelFunctionType,
     const IndexType MaxNumberOfNeighbours,
-    const IndexType EchoLevel)
+    const IndexType EchoLevel,
+    const bool NodeCloudMesh)
     : mrModelPart(rModelPart),
       mMaxNumberOfNeighbors(MaxNumberOfNeighbours),
-      mEchoLevel(EchoLevel)
+      mEchoLevel(EchoLevel),
+      mNodeCloudMesh(NodeCloudMesh)
 {
     mpKernelFunction = Kratos::make_unique<FilterFunction>(rKernelFunctionType);
 }
@@ -270,7 +283,7 @@ ContainerExpression<TContainerType> ExplicitFilterUtils<TContainerType>::Forward
         double sum_of_weights = 0.0;
         ExplicitFilterUtilsHelperUtilities::ComputeWeightForAllNeighbors(
             sum_of_weights, rTLS.mListOfWeights, *mpKernelFunction, radius,
-            entity_point, rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get());
+            entity_point, rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get(), mNodeCloudMesh);
 
         mpDamping->Apply(rTLS.mListOfDampedWeights, rTLS.mListOfWeights, Index, number_of_neighbors, rTLS.mNeighbourEntityPoints);
 
@@ -339,12 +352,12 @@ ContainerExpression<TContainerType> ExplicitFilterUtils<TContainerType>::Generic
         double sum_of_weights = 0.0;
         ExplicitFilterUtilsHelperUtilities::ComputeWeightForAllNeighbors(
             sum_of_weights, rTLS.mListOfWeights, *mpKernelFunction, radius,
-            entity_point, rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get());
+            entity_point, rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get(), mNodeCloudMesh);
 
         mpDamping->Apply(rTLS.mListOfDampedWeights, rTLS.mListOfWeights, Index, number_of_neighbors, rTLS.mNeighbourEntityPoints);
 
         const IndexType current_data_begin = Index * stride;
-        const double domain_size = ExplicitFilterUtilsHelperUtilities::GetDomainSize(entity_point, mpNodalDomainSizeExpression.get());
+        const double domain_size = ExplicitFilterUtilsHelperUtilities::GetDomainSize(entity_point, mpNodalDomainSizeExpression.get(), mNodeCloudMesh);
 
         for (IndexType j = 0; j < stride; ++j) {
             const auto& r_damped_weights = rTLS.mListOfDampedWeights[j];
@@ -394,7 +407,7 @@ void ExplicitFilterUtils<TContainerType>::GetIntegrationWeights(ContainerExpress
 
     IndexPartition<IndexType>(r_container.size()).for_each([&](const IndexType Index){
         const EntityPoint<EntityType> entity(*(r_container.begin() + Index), Index);
-        const auto integration_weight = ExplicitFilterUtilsHelperUtilities::GetDomainSize(entity, this->mpNodalDomainSizeExpression.get());
+        const auto integration_weight = ExplicitFilterUtilsHelperUtilities::GetDomainSize(entity, this->mpNodalDomainSizeExpression.get(), mNodeCloudMesh);
         const IndexType current_data_begin = Index * stride;
         for (IndexType j = 0; j < stride; ++j) {
             double& current_index_value = *(p_expression->begin() + current_data_begin + j);
@@ -458,7 +471,7 @@ void ExplicitFilterUtils<TContainerType>::CalculateMatrix(Matrix& rOutput) const
         double sum_of_weights = 0.0;
         ExplicitFilterUtilsHelperUtilities::ComputeWeightForAllNeighbors(
             sum_of_weights, list_of_weights, *mpKernelFunction, radius,
-            *mEntityPointVector[Index], rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get());
+            *mEntityPointVector[Index], rTLS.mNeighbourEntityPoints, rTLS.mResultingSquaredDistances, number_of_neighbors, this->mpNodalDomainSizeExpression.get(), mNodeCloudMesh);
 
         double* data_begin = (rOutput.data().begin() + Index * number_of_entities);
 

diff --git a/applications/OptimizationApplication/custom_utilities/filtering/explicit_filter_utils.h b/applications/OptimizationApplication/custom_utilities/filtering/explicit_filter_utils.h
@@ -63,7 +63,8 @@ class KRATOS_API(OPTIMIZATION_APPLICATION) ExplicitFilterUtils
         const ModelPart& rModelPart,
         const std::string& rKernelFunctionType,
         const IndexType MaxNumberOfNeighbours,
-        const IndexType EchoLevel);
+        const IndexType EchoLevel,
+        const bool NodeCloudMesh);
 
     ///@}
     ///@name Public operations
@@ -160,6 +161,8 @@ class KRATOS_API(OPTIMIZATION_APPLICATION) ExplicitFilterUtils
 
     typename KDTree::Pointer mpSearchTree;
 
+    bool mNodeCloudMesh;
+
     ///@}
     ///@name Private operations
     ///@{

diff --git a/applications/OptimizationApplication/python_scripts/filtering/explicit_filter.py b/applications/OptimizationApplication/python_scripts/filtering/explicit_filter.py
@@ -17,6 +17,7 @@ class ExplicitFilter(Filter):
     def GetDefaultParameters(cls) -> Kratos.Parameters:
         return Kratos.Parameters("""{
             "filter_type"               : "explicit_filter",
+            "node_cloud_mesh"               : false,
             "filter_function_type"      : "linear",
             "max_nodes_in_filter_radius": 100000,
             "echo_level"                : 0,
@@ -67,11 +68,16 @@ def Initialize(self) -> None:
         filter_function_type = self.parameters["filter_function_type"].GetString()
         max_nodes_in_filter_radius = self.parameters["max_nodes_in_filter_radius"].GetInt()
         echo_level = self.parameters["echo_level"].GetInt()
+        node_cloud_mesh = self.parameters["node_cloud_mesh"].GetBool()
         if self.data_location in [Kratos.Globals.DataLocation.NodeHistorical, Kratos.Globals.DataLocation.NodeNonHistorical]:
-            self.filter_utils = KratosOA.NodeExplicitFilterUtils(self.model_part, filter_function_type, max_nodes_in_filter_radius, echo_level)
+            self.filter_utils = KratosOA.NodeExplicitFilterUtils(self.model_part, filter_function_type, max_nodes_in_filter_radius, echo_level, node_cloud_mesh)
         elif self.data_location == Kratos.Globals.DataLocation.Condition:
+            if node_cloud_mesh == True:
+                raise RuntimeError("You need to have elements to filter variables as conditions.")
             self.filter_utils = KratosOA.ConditionExplicitFilterUtils(self.model_part, filter_function_type, max_nodes_in_filter_radius, echo_level)
         elif self.data_location == Kratos.Globals.DataLocation.Element:
+            if node_cloud_mesh == True:
+                raise RuntimeError("You need to have elements to filter variables as conditions.")
             self.filter_utils = KratosOA.ElementExplicitFilterUtils(self.model_part, filter_function_type, max_nodes_in_filter_radius, echo_level)
 
         self.Update()

diff --git a/...ptimizationApplication/tests/filtering/explicit_filter_reference_sigmoidal_cloud_mesh.vtu b/...ptimizationApplication/tests/filtering/explicit_filter_reference_sigmoidal_cloud_mesh.vtu
@@ -0,0 +1,24 @@
+<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian">
+   <UnstructuredGrid>
+      <Piece NumberOfPoints="57" NumberOfCells="85">
+         <Points>
+            <DataArray type="Float64" Name="Position" NumberOfComponents="3" format="ascii">
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+            </DataArray>
+         </Points>
+         <Cells>
+            <DataArray type="Int32" Name="connectivity" NumberOfComponents="1" format="ascii">
+              56  55  52  47  45  40  37  35  26  53  50  49  42  39  30  55  53  52  45  42  36  26  34  25  50  47  44  39  37  27  40  45  36  40  36  28  49  50  44  49  44  41  52  53  49  52  49  46  44  47  40  44  40  32  26  35  34  30  39  27  30  27  22  36  42  30  36  30  24  27  37  26  27  26  17  56  52  54  28  36  24  28  24  21  46  49  41  46  41  31  22  27  17  22  17  15  17  26  16  41  44  32  41  32  31  32  40  28  32  28  21  24  30  22  24  22  15  52  46  51  51  54  52  25  16  26  21  24  15  15  17  11  46  31  48  48  51  46  16  11  17  43  48  29  11  6  9  29  48  31  29  31  19  19  31  21  29  19  20  20  19  12  29  20  43  12  19  13  20  12  14  13  19  21  13  21  15  12  13  7  14  12  8  20  14  23  9  6  4  7  13  9  8  12  7  23  14  18  23  18  33  11  9  15  15  9  13  14  8  10  14  10  18  20  23  43  4  6  2  9  4  7  7  4  3  3  4  2  7  3  8  8  3  5  8  5  10  5  3  1  0  3  2  0  1  3  33  38  23  23  38  43  31  32  21
+            </DataArray>
+            <DataArray type="Int32" Name="offsets" NumberOfComponents="1" format="ascii">
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+            </DataArray>
+            <DataArray type="UInt8" Name="types" NumberOfComponents="1" format="ascii">
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+            </DataArray>
+         </Cells>
+         <PointData/>
+         <CellData/>
+      </Piece>
+   </UnstructuredGrid>
+</VTKFile>
diff --git a/applications/OptimizationApplication/tests/filtering/explicit_filters_tests.py b/applications/OptimizationApplication/tests/filtering/explicit_filters_tests.py
@@ -211,11 +211,15 @@ def test_FilterQuartic(self):
     def test_FilterSigmoidal(self):
         self.__RunTestCase("sigmoidal", "cosine", "explicit_filter_reference_sigmoidal.vtu")
 
-    def __RunTestCase(self, filter_function_type: str, damping_function_type: str, ref_file: str) -> None:
+    def test_FilterSigmoidalNodeCloudMesh(self):
+        self.__RunTestCase("sigmoidal", "cosine", "explicit_filter_reference_sigmoidal_cloud_mesh.vtu", True)
+
+    def __RunTestCase(self, filter_function_type: str, damping_function_type: str, ref_file: str, node_cloud_mesh=False) -> None:
         settings = Kratos.Parameters("""{
             "filter_type"               : "explicit_filter",
             "filter_function_type"      : "linear",
             "max_nodes_in_filter_radius": 100000,
+            "node_cloud_mesh": false,
             "echo_level"                : 0,
             "filter_radius_settings":{
                 "filter_radius_type": "constant",
@@ -234,6 +238,7 @@ def __RunTestCase(self, filter_function_type: str, damping_function_type: str, r
         }""")
         settings["filter_function_type"].SetString(filter_function_type)
         settings["filtering_boundary_conditions"]["damping_function_type"].SetString(damping_function_type)
+        settings["node_cloud_mesh"].SetBool(node_cloud_mesh)
         vm_filter = FilterFactory(self.model, "test", KratosOA.SHAPE, Kratos.Globals.DataLocation.NodeHistorical, settings)
         vm_filter.SetComponentDataView(ComponentDataView("test", self.optimization_problem))
         vm_filter.Initialize()