--- /dev/null
+// Copyright (C) 2014-2021 CEA/DEN, EDF R&D
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+//
+// See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
+//
+
+#include "GeomAlgoAPI_NormalToFace.h"
+
+#include <TopoDS_Shape.hxx>
+#include <TopoDS_Face.hxx>
+#include <TopoDS.hxx>
+#include <BRep_Tool.hxx>
+#include <gp_Ax3.hxx>
+#include <Geom_Plane.hxx>
+#include <gp_Pln.hxx>
+#include <TopoDS_Iterator.hxx>
+#include <GProp_GProps.hxx>
+#include <BRepGProp.hxx>
+#include <ShapeAnalysis.hxx>
+#include <ShapeAnalysis_Surface.hxx>
+#include <BRepAdaptor_Surface.hxx>
+#include <BRepBndLib.hxx>
+#include <GeomLProp_SLProps.hxx>
+#include <BRepBuilderAPI_MakeEdge.hxx>
+#include <GeomAPI_Edge.h>
+
+ /*!
+ * \brief Return type of shape for explode. In case of compound it will be a type of its first sub shape.
+ * \param theShape The shape to get type of.
+ * \retval TopAbs_ShapeEnum Return type of shape for explode.
+ */
+TopAbs_ShapeEnum GetTypeOfSimplePart(const TopoDS_Shape& theShape)
+{
+ TopAbs_ShapeEnum aType = theShape.ShapeType();
+ if (aType == TopAbs_VERTEX) return TopAbs_VERTEX;
+ else if (aType == TopAbs_EDGE || aType == TopAbs_WIRE) return TopAbs_EDGE;
+ else if (aType == TopAbs_FACE || aType == TopAbs_SHELL) return TopAbs_FACE;
+ else if (aType == TopAbs_SOLID || aType == TopAbs_COMPSOLID) return TopAbs_SOLID;
+ else if (aType == TopAbs_COMPOUND) {
+ // Only the iType of the first shape in the compound is taken into account
+ TopoDS_Iterator It (theShape, Standard_False, Standard_False);
+ if (It.More()) {
+ return GetTypeOfSimplePart(It.Value());
+ }
+ }
+ return TopAbs_SHAPE;
+}
+
+ /*!
+ * \brief Get Local Coordinate System, corresponding to the given shape.
+ * \param theShape The shape to get type of.
+ * \retval gp_Ax3 Return axis.
+ *
+ * Origin of the LCS is situated at the shape's center of mass.
+ * Axes of the LCS are obtained from shape's location or,
+ * if the shape is a planar face, from position of its plane.
+ */
+gp_Ax3 GetPosition(const TopoDS_Shape& theShape)
+{
+ gp_Ax3 aResult;
+
+ if (theShape.IsNull())
+ return aResult;
+
+ // Axes
+ aResult.Transform(theShape.Location().Transformation());
+ if (theShape.ShapeType() == TopAbs_FACE) {
+ Handle(Geom_Surface) aGS = BRep_Tool::Surface(TopoDS::Face(theShape));
+ if (!aGS.IsNull() && aGS->IsKind(STANDARD_TYPE(Geom_Plane))) {
+ Handle(Geom_Plane) aGPlane = Handle(Geom_Plane)::DownCast(aGS);
+ gp_Pln aPln = aGPlane->Pln();
+ aResult = aPln.Position();
+ // In case of reverse orinetation of the face invert the plane normal
+ // (the face's normal does not mathc the plane's normal in this case)
+ if (theShape.Orientation() == TopAbs_REVERSED) {
+ gp_Dir Vx = aResult.XDirection();
+ gp_Dir N = aResult.Direction().Mirrored(Vx);
+ gp_Pnt P = aResult.Location();
+ aResult = gp_Ax3(P, N, Vx);
+ }
+ }
+ }
+
+ // Origin
+ gp_Pnt aPnt;
+
+ TopAbs_ShapeEnum aShType = theShape.ShapeType();
+
+ if (aShType == TopAbs_VERTEX) {
+ aPnt = BRep_Tool::Pnt(TopoDS::Vertex(theShape));
+ } else {
+ if (aShType == TopAbs_COMPOUND) {
+ aShType = GetTypeOfSimplePart(theShape);
+ }
+
+ GProp_GProps aSystem;
+ if (aShType == TopAbs_EDGE || aShType == TopAbs_WIRE)
+ BRepGProp::LinearProperties(theShape, aSystem);
+ else if (aShType == TopAbs_FACE || aShType == TopAbs_SHELL)
+ BRepGProp::SurfaceProperties(theShape, aSystem);
+ else
+ BRepGProp::VolumeProperties(theShape, aSystem);
+
+ aPnt = aSystem.CentreOfMass();
+ }
+
+ aResult.SetLocation(aPnt);
+
+ return aResult;
+}
+
+//=================================================================================================
+bool GeomAlgoAPI_NormalToFace::normal(GeomShapePtr theFace,
+ GeomShapePtr thePoint,
+ GeomEdgePtr theNormal,
+ std::string& theError)
+{
+ #ifdef _DEBUG
+ std::cout << "GeomAlgoAPI_NormalToFace::normal" << std::endl;
+ #endif
+
+ if (!theFace.get()) {
+ theError = "Face for normale calculation is null";
+ return false;
+ }
+
+ TopoDS_Shape aShape = theFace->impl<TopoDS_Shape>();
+
+ if (aShape.ShapeType() != TopAbs_FACE) {
+ theError = "Shape for normale calculation is not a face";
+ return false;
+ }
+
+ TopoDS_Face aFace = TopoDS::Face(aShape);
+
+ // Point
+ gp_Pnt p1 (0,0,0);
+ // Point parameters on surface
+ double u1, u2, v1, v2;
+ Handle(Geom_Surface) aSurf = BRep_Tool::Surface(aFace);
+ Handle(ShapeAnalysis_Surface) aSurfAna = new ShapeAnalysis_Surface (aSurf);
+ gp_Ax3 aPos = GetPosition(aFace);
+ p1 = aPos.Location();
+ // Set default starting point using UV bounds
+ ShapeAnalysis::GetFaceUVBounds(aFace, u1, u2, v1, v2);
+ gp_Pnt2d pUV ((u2 + u1) * 0.5, (v2 + v1) * 0.5);
+
+ // Change to Vertex coord if selected
+ if (thePoint.get()) {
+ TopoDS_Shape anOptPnt = thePoint->impl<TopoDS_Shape>();
+ if (anOptPnt.IsNull()) {
+ theError = "Invalid shape given for point argument";
+ return false;
+ }
+ p1 = BRep_Tool::Pnt(TopoDS::Vertex(anOptPnt));
+ pUV = aSurfAna->ValueOfUV(p1, Precision::Confusion());
+ }
+
+ // Normal direction
+ gp_Vec Vec1,Vec2;
+ BRepAdaptor_Surface SF (aFace);
+ SF.D1(pUV.X(), pUV.Y(), p1, Vec1, Vec2);
+ if (Vec1.Magnitude() < Precision::Confusion()) {
+ gp_Vec tmpV;
+ gp_Pnt tmpP;
+ SF.D1(pUV.X(), pUV.Y()-0.1, tmpP, Vec1, tmpV);
+ }
+ else if (Vec2.Magnitude() < Precision::Confusion()) {
+ gp_Vec tmpV;
+ gp_Pnt tmpP;
+ SF.D1(pUV.X()-0.1, pUV.Y(), tmpP, tmpV, Vec2);
+ }
+
+ gp_Vec V = Vec1.Crossed(Vec2);
+ Standard_Real mod = V.Magnitude();
+ if (mod < Precision::Confusion())
+ Standard_NullObject::Raise("Normal vector of a face has null magnitude");
+
+ // Set length of normal vector to average radius of curvature
+ Standard_Real radius = 0.0;
+ GeomLProp_SLProps aProperties (aSurf, pUV.X(), pUV.Y(), 2, Precision::Confusion());
+ if (aProperties.IsCurvatureDefined()) {
+ Standard_Real radius1 = Abs(aProperties.MinCurvature());
+ Standard_Real radius2 = Abs(aProperties.MaxCurvature());
+ if (Abs(radius1) > Precision::Confusion()) {
+ radius = 1.0 / radius1;
+ if (Abs(radius2) > Precision::Confusion()) {
+ radius = (radius + 1.0 / radius2) / 2.0;
+ }
+ } else {
+ if (Abs(radius2) > Precision::Confusion()) {
+ radius = 1.0 / radius2;
+ }
+ }
+ }
+
+ // Set length of normal vector to average dimension of the face
+ // (only if average radius of curvature is not appropriate)
+ if (radius < Precision::Confusion()) {
+ Bnd_Box B;
+ Standard_Real Xmin, Xmax, Ymin, Ymax, Zmin, Zmax;
+ BRepBndLib::Add(aFace, B);
+ B.Get(Xmin, Ymin, Zmin, Xmax, Ymax, Zmax);
+ radius = ((Xmax - Xmin) + (Ymax - Ymin) + (Zmax - Zmin)) / 3.0;
+ }
+
+ if (radius < Precision::Confusion())
+ radius = 1.0;
+
+ V *= radius / mod;
+
+ // consider the face orientation
+ if (aFace.Orientation() == TopAbs_REVERSED ||
+ aFace.Orientation() == TopAbs_INTERNAL) {
+ V = - V;
+ }
+
+ // Edge
+ gp_Pnt p2 = p1.Translated(V);
+ BRepBuilderAPI_MakeEdge aBuilder (p1, p2);
+ if (!aBuilder.IsDone())
+ Standard_NullObject::Raise("Vector construction failed");
+ aShape = aBuilder.Shape();
+
+ theNormal->setImpl(new TopoDS_Shape(aShape));
+
+ return true;
+}
+
