0027969: Visualization - add interfaces to access selecting volumes from SelectMgr_SelectingVolumeManager

- getter for selection frustum computed during last run of selection mechanism was added to SelectMgr_SelectingVolumeManager;
- getters for frustum planes were added to SelectMgr_BaseFrustum and its successors;
- an API for applications to get frustum planes was added to SelectBasics_SelectingVolumeManager.

src/SelectBasics/SelectBasics_SelectingVolumeManager.hxx

@@ -108,6 +108,10 @@ public:
   //! correspondingly) onto far view frustum plane
   virtual gp_Pnt GetFarPickedPnt() const = 0;
 
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  virtual void GetPlanes (NCollection_Vector<NCollection_Vec4<Standard_Real> >& thePlaneEquations) const = 0;
+
 protected:
   SelectionType myActiveSelectionType;      //!< Active selection type: point, box or polyline
 };

src/SelectMgr/SelectMgr_BaseFrustum.hxx

@@ -173,6 +173,14 @@ public:
   //! @return previous value of the flag
   virtual Standard_Boolean SetViewClippingEnabled (const Standard_Boolean /*theToEnable*/) { return Standard_False; }
 
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  virtual void GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const
+  {
+    thePlaneEquations.Clear();
+    return;
+  }
+
   DEFINE_STANDARD_RTTIEXT(SelectMgr_BaseFrustum,Standard_Transient)
 
 protected:

src/SelectMgr/SelectMgr_RectangularFrustum.cxx

@@ -746,3 +746,24 @@ Standard_Boolean SelectMgr_RectangularFrustum::isViewClippingOk (const Standard_
   return myViewClipRange.MaxDepth() > theDepth
     && myViewClipRange.MinDepth() < theDepth;
 }
+
+// =======================================================================
+// function : GetPlanes
+// purpose  :
+// =======================================================================
+void SelectMgr_RectangularFrustum::GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const
+{
+  thePlaneEquations.Clear();
+
+  SelectMgr_Vec4 anEquation;
+  for (Standard_Integer aPlaneIdx = 0; aPlaneIdx < 6; ++aPlaneIdx)
+  {
+    const gp_Vec& aPlaneNorm = myIsOrthographic && aPlaneIdx % 2 == 1 ?
+      myPlanes[aPlaneIdx - 1].Reversed() : myPlanes[aPlaneIdx];
+    anEquation.x() = aPlaneNorm.X();
+    anEquation.y() = aPlaneNorm.Y();
+    anEquation.z() = aPlaneNorm.Z();
+    anEquation.w() = - (aPlaneNorm.XYZ().Dot (myVertices[aPlaneIdx % 2 == 0 ? aPlaneIdx : aPlaneIdx + 2].XYZ()));
+    thePlaneEquations.Append (anEquation);
+  }
+}

src/SelectMgr/SelectMgr_RectangularFrustum.hxx

@@ -132,6 +132,11 @@ public:
   //! of center of 2d rectangle (for point and rectangular selection
   //! correspondingly) onto far view frustum plane
   inline const gp_Pnt& GetFarPnt() const { return myFarPickedPnt; }
+
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  Standard_EXPORT virtual void GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const Standard_OVERRIDE;
+
 protected:
 
   Standard_EXPORT void segmentSegmentDistance (const gp_Pnt& theSegPnt1,

src/SelectMgr/SelectMgr_SelectingVolumeManager.hxx

@@ -196,6 +196,29 @@ public:
   //! correspondingly) onto far view frustum plane
   Standard_EXPORT virtual gp_Pnt GetFarPickedPnt() const Standard_OVERRIDE;
 
+  //! Returns active selecting volume that was built during last
+  //! run of OCCT selection mechanism
+  Handle(SelectMgr_BaseFrustum) ActiveVolume() const
+  {
+    if (myActiveSelectionType == Unknown)
+      return Handle(SelectMgr_BaseFrustum)();
+
+    return mySelectingVolumes[myActiveSelectionType / 2];
+  }
+
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  virtual void GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const Standard_OVERRIDE
+  {
+    if (myActiveSelectionType == Unknown)
+    {
+      thePlaneEquations.Clear();
+      return;
+    }
+
+    return mySelectingVolumes[myActiveSelectionType / 2]->GetPlanes (thePlaneEquations);
+  }
+
 private:
   enum { Frustum, FrustumSet, VolumeTypesNb };       //!< Defines the amount of available selecting volumes
 

src/SelectMgr/SelectMgr_TriangularFrustum.cxx

@@ -279,3 +279,21 @@ void SelectMgr_TriangularFrustum::Clear()
 {
   myBuilder.Nullify();
 }
+
+// =======================================================================
+// function : GetPlanes
+// purpose  :
+// =======================================================================
+void SelectMgr_TriangularFrustum::GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const
+{
+  SelectMgr_Vec4 aPlaneEquation;
+  for (Standard_Integer aPlaneIdx = 0; aPlaneIdx < 5; ++aPlaneIdx)
+  {
+    const gp_Vec& aNorm = myPlanes[aPlaneIdx];
+    aPlaneEquation.x() = aNorm.X();
+    aPlaneEquation.y() = aNorm.Y();
+    aPlaneEquation.z() = aNorm.Z();
+    aPlaneEquation.w() = - (aNorm.XYZ().Dot (myVertices[aPlaneIdx % 2 == 0 ? aPlaneIdx : 1].XYZ()));
+    thePlaneEquations.Append (aPlaneEquation);
+  }
+}

src/SelectMgr/SelectMgr_TriangularFrustum.hxx

@@ -84,6 +84,10 @@ public:
   //! Nullifies the handle to corresponding builder instance to prevent memory leaks
   Standard_EXPORT void Clear();
 
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  Standard_EXPORT virtual void GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const Standard_OVERRIDE;
+
 private:
 
   void cacheVertexProjections (SelectMgr_TriangularFrustum* theFrustum) const;

src/SelectMgr/SelectMgr_TriangularFrustumSet.cxx

@@ -224,4 +224,18 @@ Standard_Boolean SelectMgr_TriangularFrustumSet::Overlaps (const gp_Pnt& thePnt1
   return Standard_False;
 }
 
+// =======================================================================
+// function : GetPlanes
+// purpose  :
+// =======================================================================
+void SelectMgr_TriangularFrustumSet::GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const
+{
+  thePlaneEquations.Clear();
+
+  for (SelectMgr_TriangFrustumsIter anIter (myFrustums); anIter.More(); anIter.Next())
+  {
+    anIter.Value()->GetPlanes (thePlaneEquations);
+  }
+}
+
 #undef MEMORY_BLOCK_SIZE

src/SelectMgr/SelectMgr_TriangularFrustumSet.hxx

@@ -75,6 +75,10 @@ public:
                                                      Select3D_TypeOfSensitivity theSensType,
                                                      Standard_Real& theDepth) Standard_OVERRIDE;
 
+  //! Stores plane equation coefficients (in the following form:
+  //! Ax + By + Cz + D = 0) to the given vector
+  Standard_EXPORT virtual void GetPlanes (NCollection_Vector<SelectMgr_Vec4>& thePlaneEquations) const Standard_OVERRIDE;
+
 private:
 
     SelectMgr_TriangFrustums myFrustums;