0025926: 3D offset in mode "Complete" with Join type "Intersection"

3D offset algorithm extension for degenerate (colliding) cases.
Patch for version 6.9.1 of Open CASCADE.

It includes the following commits:

Revision: 5a9dc37f84bb8c6c7ac1e43c1dbcf484b4261321
Author: emv <emv@opencascade.com>
Date: 22/10/15 9:00:54 AM
Message:
Make the possibility to produce empty result in case of any invalidity (spikes, self-intersections, faces inversion) optional.
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cdl
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx
Modified: src/BRepTest/BRepTest_FeatureCommands.cxx

Revision: aadba9a3f585693eddff1ea29b7063a08320ee23
Author: emv <emv@opencascade.com>
Date: 16/10/15 10:21:57 AM
Message:
Due to the small inaccuracy of the calculation of the bi-normal direction (direction inside the face on the edge)

the criterion on the coincidence of these directions has been weakened.
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

Revision: 3564da4b4d631c8ed627d7ca7697328d6c371aae
Author: emv <emv@opencascade.com>
Date: 15/10/15 11:52:23 AM
Message:
The option to remove INTERNAL edges from the faces of the result of Offset operation has been added into Offset API.

By default these edges will be kept in the result.
To remove these edges make sure to set the corresponding flag to TRUE when initializing the Offset algo.

void BRepOffset_MakeOffset::Initialize(const TopoDS_Shape&    S,
                                       const Standard_Real    Offset,
                                       const Standard_Real    Tol,
                                       const BRepOffset_Mode  Mode,
                                       const Standard_Boolean Inter,
                                       const Standard_Boolean SelfInter,
                                       const GeomAbs_JoinType Join,
                                       const Standard_Boolean RemoveIntEdges,
                                       const Standard_Boolean Thickening)
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cdl
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx
Modified: src/BRepOffsetAPI/BRepOffsetAPI_MakeOffsetShape.cdl
Modified: src/BRepOffsetAPI/BRepOffsetAPI_MakeOffsetShape.cxx
Modified: src/BRepOffsetAPI/BRepOffsetAPI_MakeThickSolid.cdl
Modified: src/BRepOffsetAPI/BRepOffsetAPI_MakeThickSolid.cxx
Modified: src/BRepTest/BRepTest_FeatureCommands.cxx

Revision: fe25cda7b7
Author: emv <emv@opencascade.com>
Date: 08/10/15 12:11:06 PM
Message:
Temporary patch to produce empty result in case of any invalidity (spikes, self-intersections, faces inversion).
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

Revision: 0fe92803d2
Author: emv <emv@opencascade.com>
Date: 27/08/15 11:21:55 AM
Message:
Using local face tolerance for edges intersection.
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

Revision: 7a38094a2b
Author: emv <emv@opencascade.com>
Date: 10/07/15 12:52:58 PM
Message:
Corrections in splitting faces and making shells functions.
----
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

Revision: 2102c85e9f
Author: emv <emv@opencascade.com>
Date: 07/07/15 2:18:28 PM
Message:
3D Offset algorithm extension for the cases with the shapes having the faces connected only by the VERTEX.
----
Modified: src/BRepOffset/BRepOffset_Inter2d.cdl
Modified: src/BRepOffset/BRepOffset_Inter2d.cxx
Modified: src/BRepOffset/BRepOffset_Inter3d.cxx
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

Revision: c4362927dc
Author: emv <emv@opencascade.com>
Date: 30/06/15 12:22:42 PM
Message:
Fix for correct shells splitting when building solids.
----
Modified: src/BOPAlgo/BOPAlgo_MakerVolume.cxx
Modified: src/BOPAlgo/BOPAlgo_ShellSplitter.cxx

Revision: ee5d676aee
Author: emv <emv@opencascade.com>
Date: 17/06/15 11:30:10 AM
Message:
Treatment of the shells with free edges has been changed to keep the faces with internal edges.
----
Modified: src/BRepAlgo/BRepAlgo_Tool.cxx

Revision: 999dacb4d0
Author: emv <emv@opencascade.com>
Date: 04/06/15 10:53:22 AM
Message:
0025926: 3D offset in mode "Complete" with Join type "Intersection"

3D offset algorithm extension for degenerate (colliding) cases.
----
Modified: src/BRepOffset/BRepOffset_Inter2d.cxx
Modified: src/BRepOffset/BRepOffset_Inter3d.cxx
Modified: src/BRepOffset/BRepOffset_MakeOffset.cdl
Modified: src/BRepOffset/BRepOffset_MakeOffset.cxx

src/BRepAlgo/BRepAlgo_Tool.cxx

@@ -52,8 +52,16 @@ TopoDS_Shape BRepAlgo_Tool::Deboucle3D(const TopoDS_Shape& S,
       
       Standard_Boolean JeGarde = Standard_True;
       for ( Standard_Integer i = 1; i <= Map.Extent() && JeGarde; i++) {
-	if (Map(i).Extent() < 2) {
+        const TopTools_ListOfShape& aLF = Map(i);
-	  const TopoDS_Edge& anEdge = TopoDS::Edge(Map.FindKey(i));
+        if (aLF.Extent() < 2) {
+          const TopoDS_Edge& anEdge = TopoDS::Edge(Map.FindKey(i));
+          if (anEdge.Orientation() == TopAbs_INTERNAL) {
+            const TopoDS_Face& aFace = TopoDS::Face(aLF.First());
+            if (aFace.Orientation() != TopAbs_INTERNAL) {
+              continue;
+            }
+          }
+          //
 	  if (!Boundary.Contains(anEdge)  && 
 	      !BRep_Tool::Degenerated(anEdge) )
 	    JeGarde = Standard_False;

src/BRepOffset/BRepOffset_Inter2d.cdl

@@ -18,8 +18,8 @@
 
 class Inter2d from BRepOffset 
 
-	---Purpose: Computes the intersections betwwen edges on a face
+        ---Purpose: Computes the intersections betwwen edges on a face
-	--          stores result is SD as AsDes from BRepOffset.
+        --          stores result is SD as AsDes from BRepOffset.
 
 uses
     AsDes               from BRepAlgo,
@@ -30,27 +30,28 @@ uses
     Real                from Standard
 
 is
-    Compute(myclass ; AsDes    : AsDes      from BRepAlgo;
+    Compute(myclass ; AsDes    : AsDes             from BRepAlgo;
-    	    	      F        :         Face       from TopoDS;
+                      F        : Face              from TopoDS;
-       	    	      NewEdges :         IndexedMapOfShape from TopTools;
+                      NewEdges : IndexedMapOfShape from TopTools;
-		      Tol      :         Real       from Standard);
+                      Tol      : Real              from Standard);
-		      
+                      
-      	---Purpose: Computes the intersections between the edges stored
+              ---Purpose: Computes the intersections between the edges stored
-      	--          is AsDes as descendants of <F> . Intersections is computed
+              --          is AsDes as descendants of <F> . Intersections is computed
-      	--          between two edges if one of them is bound in NewEdges.
+              --          between two edges if one of them is bound in NewEdges.
 
     
     --  Modified by skv - Fri Dec 26 16:53:16 2003 OCC4455 Begin
     --  Add another parameter: offset value.
     ConnexIntByInt(myclass ; 
-      	    	   FI    :          Face                from TopoDS;
+                   FI      :          Face                from TopoDS;
-    	    	   OFI   : in out   Offset              from BRepOffset;
+                   OFI     : in out   Offset              from BRepOffset;
-		   MES   : in out   DataMapOfShapeShape from TopTools;  
+                   MES     : in out   DataMapOfShapeShape from TopTools;  
-		   Build :          DataMapOfShapeShape from TopTools;  
+                   Build   :          DataMapOfShapeShape from TopTools;  
-		   AsDes :  AsDes               from BRepAlgo; 
+                   AsDes   :          AsDes               from BRepAlgo; 
-    	    	   Offset:          Real                from Standard;
+                   AsDes2d :          AsDes               from BRepAlgo; 
-    	    	   Tol   :          Real                from Standard);
+                   Offset  :          Real                from Standard;
+                   Tol     :          Real                from Standard);
     --  Modified by skv - Fri Dec 26 16:53:16 2003 OCC4455 End
-			    
+                            
 end Inter2d;
 

src/BRepOffset/BRepOffset_MakeOffset.cdl

@@ -19,7 +19,7 @@
 
 class MakeOffset from BRepOffset 
 
-	---Purpose: 
+        ---Purpose: 
 
 uses
     Image                from BRepAlgo,
@@ -36,47 +36,53 @@ uses
     Edge                 from TopoDS,
     MapOfShape           from TopTools, 
     IndexedMapOfShape    from TopTools, 
-    ListOfShape          from TopTools,
+    ListOfShape          from TopTools, 
+    DataMapOfShapeShape  from TopTools, 
+    IndexedDataMapOfShapeListOfShape from TopTools,
     MakeLoops            from BRepOffset
 
 is
 
     Create;
     
-    Create ( S            : Shape    from TopoDS;
+    Create ( S              : Shape    from TopoDS;
-             Offset       : Real     from Standard;
+             Offset         : Real     from Standard;
-	     Tol          : Real     from Standard;
+             Tol            : Real     from Standard;
-	     Mode         : Mode     from BRepOffset = BRepOffset_Skin;
+             Mode           : Mode     from BRepOffset = BRepOffset_Skin;
-    	     Intersection : Boolean  from Standard   = Standard_False;
+             Intersection   : Boolean  from Standard   = Standard_False;
-	     SelfInter    : Boolean  from Standard   = Standard_False;
+             SelfInter      : Boolean  from Standard   = Standard_False;
-             Join         : JoinType from GeomAbs    = GeomAbs_Arc;
+             Join           : JoinType from GeomAbs    = GeomAbs_Arc; 
-	     Thickening   : Boolean  from Standard   = Standard_False)
+             RemoveIntEdges : Boolean  from Standard   = Standard_False;
-    returns MakeOffset from BRepOffset;	     
+             Thickening     : Boolean  from Standard   = Standard_False; 
-	     
+             RemoveInvalidFaces: Boolean from Standard = Standard_False)
+    returns MakeOffset from BRepOffset;             
+             
 ---Category: Initialization.
 
     Initialize (me : in out;
-    	        S            : Shape    from TopoDS;
+                S              : Shape    from TopoDS;
-                Offset       : Real     from Standard;
+                Offset         : Real     from Standard;
-		Tol          : Real     from Standard;
+                Tol            : Real     from Standard;
-	        Mode         : Mode     from BRepOffset = BRepOffset_Skin;
+                Mode           : Mode     from BRepOffset = BRepOffset_Skin;
-    	        Intersection : Boolean  from Standard   = Standard_False;
+                Intersection   : Boolean  from Standard   = Standard_False;
-		SelfInter    : Boolean  from Standard   = Standard_False;
+                SelfInter      : Boolean  from Standard   = Standard_False;
-                Join         : JoinType from GeomAbs    = GeomAbs_Arc; 
+                Join           : JoinType from GeomAbs    = GeomAbs_Arc; 
-		Thickening   : Boolean  from Standard   = Standard_False)
+                RemoveIntEdges : Boolean  from Standard   = Standard_False;
+                Thickening     : Boolean  from Standard   = Standard_False;
+                RemoveInvalidFaces: Boolean from Standard = Standard_False)
     is static;
     
     Clear (me : in out) 
     is static;
 
     AddFace (me : in out; F  : Face from TopoDS) is static;
-    	---Purpose: Add Closing Faces,  <F>  has to be  in  the initial
+            ---Purpose: Add Closing Faces,  <F>  has to be  in  the initial
-    	--          shape S.
+            --          shape S.
       
     SetOffsetOnFace (me  : in out; 
-    	    	     F   : Face from TopoDS;
+                             F   : Face from TopoDS;
-    	    	     Off : Real from Standard) is static;
+                             Off : Real from Standard) is static;
-    	---Purpose: set the offset <Off> on the Face <F> 
+            ---Purpose: set the offset <Off> on the Face <F> 
 
     
 ---Category: Computation.
@@ -88,7 +94,7 @@ is
 ---Category: Querying.
            
     GetAnalyse(me) 
-    	---C++: return const &
+            ---C++: return const &
     returns Analyse from BRepOffset
     is static;
 
@@ -96,18 +102,18 @@ is
     is static;
     
     Shape (me) 
-    	---C++: return const &
+            ---C++: return const &
     returns Shape from TopoDS
     is static;
 
     Error (me) returns Error from BRepOffset;
-    	---Purpose: returns information if IsDone() = FALSE.
+            ---Purpose: returns information if IsDone() = FALSE.
- 			    
+                             
 
     OffsetFacesFromShapes (me)
-	---Purpose: Returns <Image> containing links between initials
+        ---Purpose: Returns <Image> containing links between initials
- 	--          shapes and offset faces.
+         --          shapes and offset faces.
- 	---C++: return const &
+         ---C++: return const &
     returns Image from BRepAlgo
     is static;    
     
@@ -115,24 +121,24 @@ is
 -- Query offset join type.
 
     GetJoinType(me) 
-    	---Purpose: Returns myJoin.
+            ---Purpose: Returns myJoin.
     returns JoinType from GeomAbs 
     is static;
  
 -- Add methods for supporting history.
 
     OffsetEdgesFromShapes (me)
-	---Purpose: Returns <Image> containing links between initials
+        ---Purpose: Returns <Image> containing links between initials
- 	--          shapes and offset edges.
+         --          shapes and offset edges.
- 	---C++: return const &
+         ---C++: return const &
     returns Image from BRepAlgo
     is static;    
     
 -- Modified by skv - Tue Mar 15 16:17:37 2005 End
 
     ClosingFaces (me)   
-    	---Purpose: Returns the list of closing faces stores by AddFace 
+            ---Purpose: Returns the list of closing faces stores by AddFace 
-	---C++: return const &
+        ---C++: return const &
     returns IndexedMapOfShape from TopTools
     is static;
 
@@ -156,18 +162,30 @@ is
     
     BuildOffsetByInter ( me : in out )
     is static private;
-       
+ 
+    BuildSplitsOfFaces (me:in out; 
+        theLF    : ListOfShape from TopTools; 
+        theAsDes : AsDes from BRepAlgo; 
+        theOrMap : out IndexedDataMapOfShapeListOfShape from TopTools;
+        theImage : out Image from BRepAlgo;
+        theLFail : out ListOfShape from TopTools; 
+        bLimited : Boolean from Standard)
+    is static private;
+    ---Purpose: 
+    -- Building splits of the offset faces by the section curves 
+    -- between the neighboring faces. 
+ 
     SelfInter  (me    : in out ; 
-    	        Modif : in out MapOfShape from TopTools)
+                    Modif : in out MapOfShape from TopTools)
-    is static private;		
+    is static private;                
     
     Intersection3D (me        : in out;
-    	    	    Inter     : in out Inter3d from BRepOffset)
+                            Inter     : in out Inter3d from BRepOffset)
-    is static private;		    
+    is static private;                    
-		    
+ 
     Intersection2D ( me       : in out ;
                      Modif    : IndexedMapOfShape from TopTools;
-		     NewEdges : IndexedMapOfShape from TopTools)
+                     NewEdges : IndexedMapOfShape from TopTools)
     is static private;
     
     MakeLoops ( me    : in out ;
@@ -187,7 +205,7 @@ is
 
     SelectShells (me : in out)
     is static private;
-	
+        
     EncodeRegularity( me : in out)
     is static private;
 
@@ -195,20 +213,24 @@ is
     is static private;
     
     ToContext (me    : in out;
-    	       MapSF : in out DataMapOfShapeOffset from BRepOffset)
+                   MapSF : in out DataMapOfShapeOffset from BRepOffset)
-    is static private;	
+    is static private;        
     
     UpdateFaceOffset (me: in out) 
-	---Purpose: Private method use to update the map face<->offset
+        ---Purpose: Private method use to update the map face<->offset
     is static private; 
      
     CorrectConicalFaces (me: in out)
-	---Purpose: Private method used to correct degenerated edges on conical faces
+        ---Purpose: Private method used to correct degenerated edges on conical faces
     is static private; 
 
     MakeMissingWalls (me: in out)
-	---Purpose: Private method used to build walls for thickening the shell
+        ---Purpose: Private method used to build walls for thickening the shell
-    is static private; 
+    is static private;  
+     
+    RemoveInternalEdges (me: in out)
+        ---Purpose: Removes INTERNAL edges from the faces
+    is static private;  
 
 fields
 
@@ -218,13 +240,15 @@ fields
     myMode           : Mode       from BRepOffset;
     myInter          : Boolean    from Standard;
     mySelfInter      : Boolean    from Standard;
-    myJoin           : JoinType   from GeomAbs; 
+    myJoin           : JoinType   from GeomAbs;  
+    myRemoveIntEdges : Boolean    from Standard;
     myThickening     : Boolean    from Standard;
+    myRemoveInvalidFaces : Boolean from Standard;
      
     myFaceOffset     : DataMapOfShapeReal from TopTools;
     
     myFaces          : IndexedMapOfShape from TopTools;
-    myAnalyse        : Analyse	         from BRepOffset;
+    myAnalyse        : Analyse           from BRepOffset;
     
     myOffsetShape    : Shape       from TopoDS;       -- Result
     myInitOffsetFace : Image       from BRepAlgo;
@@ -240,5 +264,4 @@ fields
     myBadShape       : Shape     from TopoDS;
     myIsPerformSewing: Boolean   from Standard; -- Handle bad walls in thicksolid mode.
 
-    
 end MakeOffset;

src/BRepOffsetAPI/BRepOffsetAPI_MakeOffsetShape.cdl

@@ -46,7 +46,8 @@ is
 	     Mode         : Mode     from BRepOffset = BRepOffset_Skin;
     	     Intersection : Boolean  from Standard   = Standard_False;
 	     SelfInter    : Boolean  from Standard   = Standard_False;
-             Join         : JoinType from GeomAbs    = GeomAbs_Arc)
+             Join         : JoinType from GeomAbs    = GeomAbs_Arc;
+             RemoveIntEdges:Boolean  from Standard   = Standard_False)
     	---Purpose: Constructs a shape parallel to the shape S, where
     	-- - S may be a face, a shell, a solid or a compound of these shape kinds;
     	-- - Offset is the offset value. The offset shape is constructed:
@@ -82,6 +83,8 @@ is
     	-- - if Join is equal to GeomAbs_Intersection, then the parallels to the
     	-- two adjacent faces are enlarged and intersected,
     	-- so that there are no free edges on parallels to faces.
+        -- RemoveIntEdges flag defines whether to remove the INTERNAL edges 
+        -- from the result or not.
     	--   Warnings
     	-- 1. All the faces of the shape S should be based on the surfaces
     	-- with continuity at least C1.

src/BRepOffsetAPI/BRepOffsetAPI_MakeOffsetShape.cxx

@@ -43,9 +43,11 @@ BRepOffsetAPI_MakeOffsetShape::BRepOffsetAPI_MakeOffsetShape
  const BRepOffset_Mode  Mode, 
  const Standard_Boolean Intersection,
  const Standard_Boolean SelfInter,
- const GeomAbs_JoinType Join)
+ const GeomAbs_JoinType Join,
+ const Standard_Boolean RemoveIntEdges)
 {
-  myOffsetShape.Initialize (S,Offset,Tol,Mode,Intersection,SelfInter,Join);
+  myOffsetShape.Initialize (S,Offset,Tol,Mode,Intersection,SelfInter,
+                            Join, RemoveIntEdges);
   Build();
 }
 

src/BRepOffsetAPI/BRepOffsetAPI_MakeThickSolid.cdl

@@ -53,7 +53,8 @@ is
 	     Mode         : Mode        from BRepOffset = BRepOffset_Skin;
     	     Intersection : Boolean     from Standard   = Standard_False;
 	     SelfInter    : Boolean     from Standard   = Standard_False;
-             Join         : JoinType    from GeomAbs    = GeomAbs_Arc)
+             Join         : JoinType    from GeomAbs    = GeomAbs_Arc;
+             RemoveIntEdges : Boolean   from Standard   = Standard_False)
     	---Purpose:  Constructs a hollowed solid from
     	-- the solid S by removing the set of faces ClosingFaces from S, where:
     	--       Offset defines the thickness of the walls. Its sign indicates
@@ -88,6 +89,8 @@ is
     	--   then the parallels to the two adjacent faces are
     	--   enlarged and intersected, so that there are no free
     	--   edges on parallels to faces.
+        -- - RemoveIntEdges flag defines whether to remove the INTERNAL edges 
+        --   from the result or not.
     	--   Warnings
     	-- Since the algorithm of MakeThickSolid is based on
     	-- MakeOffsetShape algorithm, the warnings are the same as for

src/BRepOffsetAPI/BRepOffsetAPI_MakeThickSolid.cxx

@@ -44,9 +44,11 @@ BRepOffsetAPI_MakeThickSolid::BRepOffsetAPI_MakeThickSolid
  const BRepOffset_Mode       Mode,
  const Standard_Boolean      Intersection,
  const Standard_Boolean      SelfInter,
- const GeomAbs_JoinType      Join)
+ const GeomAbs_JoinType      Join,
+ const Standard_Boolean      RemoveIntEdges)
 {
-  myOffsetShape.Initialize (S,Offset,Tol,Mode,Intersection,SelfInter,Join);
+  myOffsetShape.Initialize (S,Offset,Tol,Mode,Intersection,SelfInter,
+                            Join, RemoveIntEdges);
   TopTools_ListIteratorOfListOfShape it(ClosingFaces);
   for (; it.More(); it.Next()) {
     myOffsetShape.AddFace(TopoDS::Face(it.Value()));

src/BRepTest/BRepTest_FeatureCommands.cxx

@@ -803,7 +803,7 @@ static Standard_Integer SPLS(Draw_Interpretor& ,
 //=======================================================================
 
 Standard_Integer thickshell(Draw_Interpretor& ,
-			    Standard_Integer n, const char** a)
+                            Standard_Integer n, const char** a)
 {
 
   //OSD_Chronometer Clock;
@@ -818,9 +818,9 @@ Standard_Integer thickshell(Draw_Interpretor& ,
   if (n > 4)
     {
       if (!strcmp(a[4],"i"))
-	JT = GeomAbs_Intersection;
+        JT = GeomAbs_Intersection;
       if (!strcmp(a[4],"t"))
-	JT = GeomAbs_Tangent;
+        JT = GeomAbs_Tangent;
     }
   
   Standard_Boolean Inter = Standard_False; //Standard_True;
@@ -829,7 +829,7 @@ Standard_Integer thickshell(Draw_Interpretor& ,
     Tol = Draw::Atof(a[5]);
 
   BRepOffset_MakeOffset B;
-  B.Initialize(S,Of,Tol,BRepOffset_Skin,Inter,0,JT, Standard_True);
+  B.Initialize(S,Of,Tol,BRepOffset_Skin,Inter,0,JT, Standard_False, Standard_True);
 
 //  Clock.Start();
 
@@ -849,7 +849,7 @@ Standard_Integer thickshell(Draw_Interpretor& ,
 //=======================================================================
 
 Standard_Integer offsetshape(Draw_Interpretor& ,
-			     Standard_Integer n, const char** a)
+                             Standard_Integer n, const char** a)
 {
 
   //OSD_Chronometer Clock;
@@ -907,63 +907,73 @@ static Standard_Boolean      theYaBouchon;
 static Standard_Real         TheTolerance = Precision::Confusion();
 static Standard_Boolean      TheInter     = Standard_False;
 static GeomAbs_JoinType      TheJoin      = GeomAbs_Arc;
+static Standard_Boolean      RemoveIntEdges = Standard_False;
+static Standard_Boolean      RemoveInvalidFaces = Standard_False;
 
 Standard_Integer offsetparameter(Draw_Interpretor& di,
-				 Standard_Integer n, const char** a)
+                                 Standard_Integer n, const char** a)
 {
   if ( n == 1 ) { 
-    //cout << " OffsetParameter Tol Inter(c/p) JoinType(a/i)" << endl;
+    di << " OffsetParameter Tol Inter(c/p) JoinType(a/i/t) [RemoveInternalEdges(r/k) RemoveInvalidFaces(r/k)]" << "\n";
-    //cout << " Current Values" << endl;
-    //cout << "   --> Tolerance :" << TheTolerance << endl;
-    //cout << "   --> TheInter  :";
-    di << " OffsetParameter Tol Inter(c/p) JoinType(a/i)" << "\n";
     di << " Current Values" << "\n";
-    di << "   --> Tolerance :" << TheTolerance << "\n";
+    di << "   --> Tolerance : " << TheTolerance << "\n";
-    di << "   --> TheInter  :";
+    di << "   --> TheInter  : ";
     if ( TheInter) {
-      //cout << "Complet" ;
       di << "Complet" ;
     } else {
-      //cout << "Partial";
       di << "Partial";
     }
-    //cout << endl << "   --> TheJoin   :";
+    di << "\n" << "   --> TheJoin   : ";
-    di << "\n" << "   --> TheJoin   :";
     
     switch (TheJoin) {
-    //case GeomAbs_Arc:          cout << " Arc";          break;
+    case GeomAbs_Arc:          di << "Arc";          break;
-    //case GeomAbs_Intersection: cout << " Intersection"; break;
+    case GeomAbs_Intersection: di << "Intersection"; break;
-    case GeomAbs_Arc:          di << " Arc";          break;
-    case GeomAbs_Intersection: di << " Intersection"; break;
     default:
       break ;
     }
-    //cout << endl;
+    //
+    di << "\n" << "   --> Internal Edges : ";
+    if (RemoveIntEdges) {
+      di << "Remove";
+    }
+    else {
+      di << "Keep";
+    }
+    //
+    di << "\n" << "   --> Invalid Faces : ";
+    if (RemoveInvalidFaces) {
+      di << "Remove";
+    }
+    else {
+      di << "Keep";
+    }
     di << "\n";
-
+    //
     return 0;
   }
 
   if ( n < 4 ) return 1;
-  
+  //
   TheTolerance = Draw::Atof(a[1]);
   TheInter     = strcmp(a[2],"p");
-  
+  //
   if      ( !strcmp(a[3],"a")) TheJoin = GeomAbs_Arc;
   else if ( !strcmp(a[3],"i")) TheJoin = GeomAbs_Intersection;
   else if ( !strcmp(a[3],"t")) TheJoin = GeomAbs_Tangent;
-    
+  //
-  return 0;    
+  RemoveIntEdges = (n >= 5) ? !strcmp(a[4], "r") : Standard_False;
+  RemoveInvalidFaces = (n == 6) ? !strcmp(a[5], "r") : Standard_False;
+  //
+  return 0;
 }
 
-
 //=======================================================================
 //function : offsetinit
 //purpose  : 
 //=======================================================================
 
 Standard_Integer offsetload(Draw_Interpretor& ,
-			    Standard_Integer n, const char** a)
+                            Standard_Integer n, const char** a)
 {
   if ( n < 2) return 1;
   TopoDS_Shape  S  = DBRep::Get(a[1]);
@@ -973,7 +983,8 @@ Standard_Integer offsetload(Draw_Interpretor& ,
   TheRadius = Of;
 //  Standard_Boolean Inter = Standard_True;
   
-  TheOffset.Initialize(S,Of,TheTolerance,BRepOffset_Skin,TheInter,0,TheJoin);
+  TheOffset.Initialize(S,Of,TheTolerance,BRepOffset_Skin,TheInter,0,TheJoin,
+                       RemoveIntEdges,Standard_False,RemoveInvalidFaces);
   //------------------------------------------
   // recuperation et chargement des bouchons.
   //----------------------------------------
@@ -1076,7 +1087,7 @@ Standard_Integer offsetperform(Draw_Interpretor& theCommands,
 //=======================================================================
 
 static Standard_Integer Debou(Draw_Interpretor& theCommands,
-			      Standard_Integer narg, const char** a)
+                              Standard_Integer narg, const char** a)
 {
   Standard_Integer i ;
   Standard_Integer newnarg ;