0027945: Visualization - handle correctly view clipping planes within zoom-persistent objects

OpenGl_Structure::Render() and SelectMgr_ViewerSelector::checkOverlap()
now clip entire zoom/rotate persistence object
by checking anchor point with global clipping planes.

Image dump has been added to the new test case.

src/SelectMgr/SelectMgr_SelectingVolumeManager.cxx

@@ -60,6 +60,7 @@ SelectMgr_SelectingVolumeManager SelectMgr_SelectingVolumeManager::ScaleAndTrans
     = mySelectingVolumes[myActiveSelectionType / 2]->ScaleAndTransform (theScaleFactor, theTrsf);
   aMgr.myToAllowOverlap = myToAllowOverlap;
   aMgr.mySelectingVolumes[myActiveSelectionType / 2]->SetBuilder (theBuilder);
+  aMgr.myViewClipPlanes = myViewClipPlanes;
 
   return aMgr;
 }
@@ -469,6 +470,7 @@ gp_Pnt SelectMgr_SelectingVolumeManager::GetFarPickedPnt() const
 //=======================================================================
 void SelectMgr_SelectingVolumeManager::SetViewClipping (const Handle(Graphic3d_SequenceOfHClipPlane)& thePlanes)
 {
+  myViewClipPlanes = thePlanes;
   if (myActiveSelectionType != Point)
     return;
 

src/SelectMgr/SelectMgr_SelectingVolumeManager.hxx

@@ -170,6 +170,9 @@ public:
 
   Standard_EXPORT virtual Standard_Boolean IsOverlapAllowed() const Standard_OVERRIDE;
 
+  //! Return view clipping planes.
+  const Handle(Graphic3d_SequenceOfHClipPlane)& ViewClipping() const { return myViewClipPlanes; }
+
   //! Valid for point selection only!
   //! Computes depth range for global (defined for the whole view) clipping planes.
   Standard_EXPORT void SetViewClipping (const Handle(Graphic3d_SequenceOfHClipPlane)& thePlanes);
@@ -196,8 +199,9 @@ public:
 private:
   enum { Frustum, FrustumSet, VolumeTypesNb };       //!< Defines the amount of available selecting volumes
 
-  Handle(SelectMgr_BaseFrustum) mySelectingVolumes[VolumeTypesNb];      //!< Array of selecting volumes
-  Standard_Boolean              myToAllowOverlap;      //!< Defines if partially overlapped entities will me detected or not
+  Handle(SelectMgr_BaseFrustum)          mySelectingVolumes[VolumeTypesNb]; //!< Array of selecting volumes
+  Handle(Graphic3d_SequenceOfHClipPlane) myViewClipPlanes;                  //!< view clipping planes
+  Standard_Boolean                       myToAllowOverlap;                  //!< Defines if partially overlapped entities will me detected or not
 };
 
-#endif
+#endif

src/SelectMgr/SelectMgr_ViewerSelector.cxx

@@ -176,12 +176,44 @@ void SelectMgr_ViewerSelector::checkOverlap (const Handle(SelectBasics_Sensitive
   if (!anOwner.IsNull())
   {
     aSelectable = anOwner->Selectable();
-    if ((!aSelectable->TransformPersistence().IsNull() && aSelectable->TransformPersistence()->IsTrihedronOr2d())
-     || (!aSelectable->ClipPlanes().IsNull() && aSelectable->ClipPlanes()->ToOverrideGlobal()))
+    if (!aSelectable->ClipPlanes().IsNull()
+      && aSelectable->ClipPlanes()->ToOverrideGlobal())
     {
       theMgr.SetViewClippingEnabled (Standard_False);
       toRestoresViewClipEnabled = Standard_True;
     }
+    else if (!aSelectable->TransformPersistence().IsNull())
+    {
+      if (aSelectable->TransformPersistence()->IsZoomOrRotate()
+      && !theMgr.ViewClipping().IsNull())
+      {
+        // Zoom/rotate persistence object lives in two worlds at the same time.
+        // Global clipping planes can not be trivially applied without being converted
+        // into local space of transformation persistence object.
+        // As more simple alternative - just clip entire object by its anchor point defined in the world space.
+        const Handle(Graphic3d_SequenceOfHClipPlane)& aViewPlanes = theMgr.ViewClipping();
+
+        const gp_Pnt anAnchor = aSelectable->TransformPersistence()->AnchorPoint();
+        for (Graphic3d_SequenceOfHClipPlane::Iterator aPlaneIt (*aViewPlanes); aPlaneIt.More(); aPlaneIt.Next())
+        {
+          const Handle(Graphic3d_ClipPlane)& aPlane = aPlaneIt.Value();
+          if (!aPlane->IsOn())
+          {
+            continue;
+          }
+
+          const Graphic3d_Vec4d& aPlaneEquation = aPlane->GetEquation();
+          const Graphic3d_Vec4d  aCheckPnt (anAnchor.X(), anAnchor.Y(), anAnchor.Z(), 1.0);
+          if (aPlaneEquation.Dot (aCheckPnt) < 0.0) // vertex is outside the half-space
+          {
+            return;
+          }
+        }
+      }
+
+      theMgr.SetViewClippingEnabled (Standard_False);
+      toRestoresViewClipEnabled = Standard_True;
+    }
   }
 
   SelectBasics_PickResult aPickResult;