0023407: Draw face outlines for XDE objects

FaceOutline aspect and flag added to AIS_Drawer, Prs3d_Drawer.cdl
FaceOutlines computed by StdPrs_ShadedShape and build upon the edge triangulation.
"vshowoutlines" draw command for testing outlines on AIS_Shapes,
"XShowOutlines" draw command for testing outlines on XCAF objects.
remarks corrected:
- FaceOutline renamed to FaceBoundary
- Graphic3d_ArrayOfSegments with edges used instead of Graphic3d_ArrayOfPolylines with bounds.
draw boundaries in separate Graphic3d_Group.
Adding test cases bugs/vis/CR23407_1 CR23407_2

src/AIS/AIS_Drawer.cdl

@@ -478,7 +478,42 @@ is
     	--          Type of line: Aspect_TOL_SOLID Width: 1.
     is redefined static;
     
+    SetFaceBoundaryDraw (me           : mutable;
+                         theIsEnabled : Boolean from Standard)
+    is redefined static;
+        ---Purpose: Enables or disables drawing of face boundaries for shading presentations.
+        -- The method sets drawing flag owned by the drawer that will be used during
+        -- visualization instead of the one set in link.
+        -- theIsEnabled is a boolean flag indicating whether the face boundaries should be
+        -- drawn or not.
 
+    IsFaceBoundaryDraw (me) returns Boolean from Standard
+    is redefined static;
+        ---Purpose: Checks whether the drawing of face boundaries is enabled or not.
+
+    SetFaceBoundaryAspect (me        : mutable;
+                           theAspect : LineAspect from Prs3d)
+    is redefined static;
+        ---Purpose: Sets line aspect for face boundaries.
+        -- The method sets line aspect owned by the drawer that will be used during
+        -- visualization instead of the one set in link.
+        -- theAspect is the line aspect that determines the look of the face boundaries.
+
+    FaceBoundaryAspect (me : mutable) returns mutable LineAspect from Prs3d
+    is redefined static;
+        ---Purpose: Returns line aspect of face boundaries.
+
+    IsOwnFaceBoundaryDraw (me) returns Boolean from Standard
+    is static;
+        ---Purpose: Returns true if the drawer has its own attribute for 
+        -- "draw face boundaries" flag that overrides the one in the link.
+        ---C++: inline
+
+    IsOwnFaceBoundaryAspect (me) returns Boolean from Standard
+    is static;
+        ---Purpose: Returns true if the drawer has its own attribute for 
+        -- face boundaries aspect that overrides the one in the link.
+        ---C++: inline
 --
 --  Attributes for the presentation of a Datum.
 --  
@@ -593,6 +628,7 @@ fields
     myOwnHLRDeviationAngle           : Real from Standard; 
     myPreviousHLRDeviationAngle      : Real from Standard; 	 	
 
+	myHasOwnFaceBoundaryDraw         : Boolean from Standard;
 end Drawer;
  
 

src/AIS/AIS_Drawer.cxx

@@ -26,7 +26,8 @@ myhasOwnDeviationCoefficient(Standard_False),
 myPreviousDeviationCoefficient(0.1),
 myhasOwnHLRDeviationCoefficient (Standard_False),
 myhasOwnDeviationAngle (Standard_False),
-myhasOwnHLRDeviationAngle (Standard_False)
+myhasOwnHLRDeviationAngle (Standard_False),
+myHasOwnFaceBoundaryDraw (Standard_False)
 {
   SetMaximalParameterValue(500000.);
   myLink->SetMaximalParameterValue(500000.);
@@ -262,10 +263,58 @@ void AIS_Drawer::ClearLocalAttributes()
   if(!myRadiusAspect.IsNull())  myRadiusAspect.Nullify();    
   if(!mySectionAspect.IsNull())  mySectionAspect.Nullify();   
   if( myhasOwnHLRDeviationCoefficient )  myhasOwnHLRDeviationCoefficient = Standard_False;   
-  if(myhasOwnHLRDeviationAngle ) myhasOwnHLRDeviationAngle  = Standard_False;   
+  if(myhasOwnHLRDeviationAngle ) myhasOwnHLRDeviationAngle  = Standard_False;
+  if (!myFaceBoundaryAspect.IsNull()) myFaceBoundaryAspect.Nullify();
   
+  myHasOwnFaceBoundaryDraw = Standard_False;
+
   hasLocalAttributes = Standard_False;
 
 }
 
+// =======================================================================
+// function : SetFaceBoundaryDraw
+// purpose  :
+// =======================================================================
+void AIS_Drawer::SetFaceBoundaryDraw (const Standard_Boolean theIsEnabled)
+{
+  myHasOwnFaceBoundaryDraw = Standard_True;
+  myFaceBoundaryDraw       = theIsEnabled;
+}
 
+// =======================================================================
+// function : IsFaceBoundaryDraw
+// purpose  :
+// =======================================================================
+Standard_Boolean AIS_Drawer::IsFaceBoundaryDraw() const
+{
+  if (!IsOwnFaceBoundaryDraw ())
+  {
+    return myLink->IsFaceBoundaryDraw ();
+  }
+
+  return myFaceBoundaryDraw;
+}
+
+// =======================================================================
+// function : SetFaceBoundaryAspect
+// purpose  :
+// =======================================================================
+void AIS_Drawer::SetFaceBoundaryAspect (const Handle(Prs3d_LineAspect)& theAspect)
+{
+  myFaceBoundaryAspect = theAspect;
+}
+
+// =======================================================================
+// function : FaceBoundaryAspect
+// purpose  :
+// =======================================================================
+Handle_Prs3d_LineAspect AIS_Drawer::FaceBoundaryAspect()
+{
+  if (!IsOwnFaceBoundaryAspect ())
+  {
+    return myLink->FaceBoundaryAspect ();
+  }
+
+  return myFaceBoundaryAspect;
+}

src/AIS/AIS_Drawer.lxx

@@ -94,3 +94,8 @@ inline Standard_Boolean AIS_Drawer::HasPlaneAspect ()  const
 inline Standard_Boolean AIS_Drawer::HasLengthAspect ()  const 
 { return !myLengthAspect.IsNull();}
 
+inline Standard_Boolean AIS_Drawer::IsOwnFaceBoundaryDraw () const
+{ return myHasOwnFaceBoundaryDraw; }
+
+inline Standard_Boolean AIS_Drawer::IsOwnFaceBoundaryAspect () const
+{ return !myFaceBoundaryAspect.IsNull (); }