0023129: BRepTools::OuterShell() works wrong - it always returns the first shell

src/BRepClass3d/BRepClass3d.cdl

@@ -46,22 +46,19 @@ is
        DataMap from TCollection(Shape          from TopoDS,
 	    	    	    	Address        from Standard,
                                 ShapeMapHasher from TopTools);
-				
 
     class SolidExplorer;
         
-    class SolidPassiveClassifier instantiates Classifier3d from TopClass
-    	(Intersector3d  from BRepClass3d);
+    class SolidPassiveClassifier instantiates  
+    	Classifier3d from TopClass  (Intersector3d  from BRepClass3d);
 
-    ---class SClassifier instantiates SolidClassifier from TopClass
-    ---   (SolidExplorer from BRepClass3d,
-    ---	Intersector3d from BRepClass3d);
-     
-    
     class SClassifier;       
 
     class SolidClassifier;
-    
        
+    OuterShell(S : Solid from TopoDS)  
+    	    returns Shell from TopoDS;
+	---Purpose: Returns the outer most shell of <S>. Returns a Null
+	--          shell if <S> has no outer shell. 
        
 end BRepClass3d;

src/BRepClass3d/BRepClass3d.cxx

@@ -0,0 +1,112 @@
+// Created on: 1993-01-21
+// Created by: Peter KURNEV
+// Copyright (c) 1993-1999 Matra Datavision
+// Copyright (c) 1999-2012 OPEN CASCADE SAS
+//
+// The content of this file is subject to the Open CASCADE Technology Public
+// License Version 6.5 (the "License"). You may not use the content of this file
+// except in compliance with the License. Please obtain a copy of the License
+// at http://www.opencascade.org and read it completely before using this file.
+//
+// The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
+// main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
+//
+// The Original Code and all software distributed under the License is
+// distributed on an "AS IS" basis, without warranty of any kind, and the
+// Initial Developer hereby disclaims all such warranties, including without
+// limitation, any warranties of merchantability, fitness for a particular
+// purpose or non-infringement. Please see the License for the specific terms
+// and conditions governing the rights and limitations under the License.
+
+// File:	BRepClass3d.cxx
+// Created:	Thu Sep 20 10:05:46 2012
+// Author:	
+//		<pkv@PETREX>
+
+#include <BRepClass3d.ixx>
+
+
+#include <TopAbs_State.hxx>
+#include <TopAbs_Orientation.hxx>
+
+#include <TopoDS_Solid.hxx>
+#include <TopoDS_Shell.hxx>
+#include <TopoDS_Iterator.hxx>
+
+#include <BRep_Builder.hxx>
+#include <BRepClass3d_SolidClassifier.hxx>
+
+
+static 
+  Standard_Boolean IsInternal(const TopoDS_Shell& aSx);
+
+//=======================================================================
+//function : OuterShell
+//purpose  : 
+//=======================================================================
+TopoDS_Shell BRepClass3d::OuterShell(const TopoDS_Solid& aSolid)
+{
+  Standard_Boolean bFound;
+  Standard_Real aTol;
+  TopoDS_Solid aSDx;
+  TopoDS_Shell aShell, aDummy;
+  TopoDS_Iterator aIt;
+  BRep_Builder aBB;
+  BRepClass3d_SolidClassifier aSC;
+  //
+  if (aSolid.IsNull()) {
+    return aDummy;
+  }
+  //
+  aTol=1.e-7;
+  bFound=Standard_False;
+  //
+  aIt.Initialize(aSolid);
+  for (; aIt.More(); aIt.Next()) { 
+    const TopoDS_Shape& aSx=aIt.Value();
+    if (aSx.ShapeType()==TopAbs_SHELL) {
+      aShell=*((TopoDS_Shell*)&aSx);
+      if (!IsInternal(aShell)) {
+	aSDx=aSolid;
+	aSDx.EmptyCopy();
+	aBB.Add(aSDx, aShell);
+	//
+	aSC.Load(aSDx);
+	aSC.PerformInfinitePoint(aTol);
+	if(aSC.State()==TopAbs_OUT) {
+	  bFound=Standard_True;
+	  break;
+	}
+      }
+    }
+  }
+  //
+  if (!bFound) {
+    return aDummy;
+  } 
+  //
+  return aShell;
+}
+
+//=======================================================================
+//function : IsInternal
+//purpose  : 
+//=======================================================================
+Standard_Boolean IsInternal(const TopoDS_Shell& aSx)
+{
+  Standard_Boolean bInternal;
+  TopAbs_Orientation aOr;
+  TopoDS_Iterator aIt; 
+  //
+  bInternal=Standard_False;
+  //
+  aIt.Initialize(aSx);
+  for (; aIt.More(); aIt.Next()) {
+    const TopoDS_Shape& aSy=aIt.Value();
+    aOr=aSy.Orientation();
+    bInternal=(aOr==TopAbs_INTERNAL);
+    break;
+  }	
+  //
+  return bInternal;
+}