0026940: Visualization, TKOpenGl - capping plane should be applied to connected structures

OpenGl_Structure::Render(), OpenGl_CappingAlgo::RenderCapping() - render
groups of instanced and this structure in the same manner
using ::renderGeometry() and ::renderClosedGeometry() instead of ::DrawGroups().
Skip capping algo for structures without groups of closed primitives.

src/OpenGl/OpenGl_CappingAlgo.cxx

@@ -37,8 +37,8 @@ namespace
 // function : RenderCapping
 // purpose  :
 // =======================================================================
-void OpenGl_CappingAlgo::RenderCapping (const Handle(OpenGl_Workspace)&  theWorkspace,
+void OpenGl_CappingAlgo::RenderCapping (const Handle(OpenGl_Workspace)& theWorkspace,
-                                        const Graphic3d_SequenceOfGroup& theGroups)
+                                        const OpenGl_Structure&         theStructure)
 {
   const Handle(OpenGl_Context)& aContext = theWorkspace->GetGlContext();
 
@@ -110,13 +110,8 @@ void OpenGl_CappingAlgo::RenderCapping (const Handle(OpenGl_Workspace)&  theWork
     glStencilFunc (GL_ALWAYS, 1, 0x01);
     glStencilOp (GL_KEEP, GL_INVERT, GL_INVERT);
 
-    for (OpenGl_Structure::GroupIterator aGroupIt (theGroups); aGroupIt.More(); aGroupIt.Next())
+    // render closed primitives
-    {
+    theStructure.renderClosedGeometry (theWorkspace);
-      if (aGroupIt.Value()->IsClosed())
-      {
-        aGroupIt.Value()->Render (theWorkspace);
-      }
-    }
 
     // override material, cull back faces
     theWorkspace->SetAspectFace (&theWorkspace->FrontCulling());

src/OpenGl/OpenGl_CappingAlgo.hxx

@@ -19,10 +19,9 @@
 #include <OpenGl_RenderFilter.hxx>
 #include <OpenGl_Group.hxx>
 
-#include <Graphic3d_SequenceOfGroup.hxx>
-
 // Forward declaration
 class OpenGl_CappingAlgoFilter;
+class OpenGl_Structure;
 DEFINE_STANDARD_HANDLE (OpenGl_CappingAlgoFilter, OpenGl_RenderFilter)
 
 //! Capping surface rendering algorithm.
@@ -30,13 +29,12 @@ class OpenGl_CappingAlgo
 {
 public:
 
-  //! Draw capping surfaces by OpenGl for the clipping planes
+  //! Draw capping surfaces by OpenGl for the clipping planes enabled in current context state.
-  //! enabled in current context state. Depth buffer must be generated
+  //! Depth buffer must be generated  for the passed groups.
-  //! for the passed groups.
+  //! @param theWorkspace [in] the GL workspace, context state
-  //! @param theWorkspace [in] the GL workspace, context state.
+  //! @param theStructure [in] the structure to be capped
-  //! @param theGroups [in] the group of primitives to be capped.
+  Standard_EXPORT static void RenderCapping (const Handle(OpenGl_Workspace)& theWorkspace,
-  Standard_EXPORT static void RenderCapping (const Handle(OpenGl_Workspace)&  theWorkspace,
+                                             const OpenGl_Structure&         theStructure);
-                                             const Graphic3d_SequenceOfGroup& theGroups);
 
   //! Render infinite capping plane.
   //! @param theWorkspace [in] the GL workspace, context state.

src/OpenGl/OpenGl_Structure.cxx

@@ -490,19 +490,44 @@ void OpenGl_Structure::Clear (const Handle(OpenGl_Context)& theGlCtx)
 }
 
 // =======================================================================
-// function : RenderGeometry
+// function : renderGeometry
 // purpose  :
 // =======================================================================
-void OpenGl_Structure::RenderGeometry (const Handle(OpenGl_Workspace) &theWorkspace) const
+void OpenGl_Structure::renderGeometry (const Handle(OpenGl_Workspace)& theWorkspace,
+                                       bool&                           theHasClosed) const
 {
-  // Render groups
+  if (myInstancedStructure != NULL)
-  const Graphic3d_SequenceOfGroup& aGroups = DrawGroups();
-  for (OpenGl_Structure::GroupIterator aGroupIter (aGroups); aGroupIter.More(); aGroupIter.Next())
   {
+    myInstancedStructure->renderGeometry (theWorkspace, theHasClosed);
+  }
+
+  for (OpenGl_Structure::GroupIterator aGroupIter (myGroups); aGroupIter.More(); aGroupIter.Next())
+  {
+    theHasClosed = theHasClosed || aGroupIter.Value()->IsClosed();
     aGroupIter.Value()->Render (theWorkspace);
   }
 }
 
+// =======================================================================
+// function : renderClosedGeometry
+// purpose  :
+// =======================================================================
+void OpenGl_Structure::renderClosedGeometry (const Handle(OpenGl_Workspace)& theWorkspace) const
+{
+  if (myInstancedStructure != NULL)
+  {
+    myInstancedStructure->renderClosedGeometry (theWorkspace);
+  }
+
+  for (OpenGl_Structure::GroupIterator aGroupIter (myGroups); aGroupIter.More(); aGroupIter.Next())
+  {
+    if (aGroupIter.Value()->IsClosed())
+    {
+      aGroupIter.Value()->Render (theWorkspace);
+    }
+  }
+}
+
 // =======================================================================
 // function : Render
 // purpose  :
@@ -585,12 +610,6 @@ void OpenGl_Structure::Render (const Handle(OpenGl_Workspace) &theWorkspace) con
   if (myHighlightColor)
     theWorkspace->HighlightColor = myHighlightColor;
 
-  // Render instanced structure (if exists)
-  if (myInstancedStructure != NULL)
-  {
-    myInstancedStructure->RenderGeometry (theWorkspace);
-  }
-
   // Set up plane equations for non-structure transformed global model-view matrix
   // List of planes to be applied to context state
   NCollection_Handle<Graphic3d_SequenceOfHClipPlane> aUserPlanes;
@@ -629,11 +648,8 @@ void OpenGl_Structure::Render (const Handle(OpenGl_Workspace) &theWorkspace) con
   }
 
   // Render groups
-  const Graphic3d_SequenceOfGroup& aGroups = DrawGroups();
+  bool hasClosedPrims = false;
-  for (OpenGl_Structure::GroupIterator aGroupIter (aGroups); aGroupIter.More(); aGroupIter.Next())
+  renderGeometry (theWorkspace, hasClosedPrims);
-  {
-    aGroupIter.Value()->Render (theWorkspace);
-  }
 
   // Reset correction for mirror transform
   if (myIsMirrored)
@@ -642,9 +658,10 @@ void OpenGl_Structure::Render (const Handle(OpenGl_Workspace) &theWorkspace) con
   }
 
   // Render capping for structure groups
-  if (!aCtx->Clipping().Planes().IsEmpty())
+  if (hasClosedPrims
+  && !aCtx->Clipping().Planes().IsEmpty())
   {
-    OpenGl_CappingAlgo::RenderCapping (theWorkspace, aGroups);
+    OpenGl_CappingAlgo::RenderCapping (theWorkspace, *this);
   }
 
   // Revert structure clippings

src/OpenGl/OpenGl_Structure.hxx

@@ -130,7 +130,13 @@ public:
   Standard_EXPORT void Clear (const Handle(OpenGl_Context)& theGlCtx);
 
   //! Renders groups of structure without applying any attributes (i.e. transform, material etc).
-  virtual void RenderGeometry  (const Handle(OpenGl_Workspace)& theWorkspace) const;
+  //! @param theWorkspace current workspace
+  //! @param theHasClosed flag will be set to TRUE if structure contains at least one group of closed primitives
+  virtual void renderGeometry (const Handle(OpenGl_Workspace)& theWorkspace,
+                               bool&                           theHasClosed) const;
+
+  //! Renders groups of closed primitives without applying any attributes (i.e. transform, material etc).
+  virtual void renderClosedGeometry (const Handle(OpenGl_Workspace)& theWorkspace) const;
 
   //! Renders the structure.
   virtual void Render  (const Handle(OpenGl_Workspace)& theWorkspace) const;

src/OpenGl/OpenGl_StructureShadow.hxx

@@ -28,9 +28,23 @@ public:
   Standard_EXPORT OpenGl_StructureShadow (const Handle(Graphic3d_StructureManager)& theManager,
                                           const Handle(OpenGl_Structure)&           theStructure);
 
+  //! Return groups of parent structure.
   virtual const Graphic3d_SequenceOfGroup& DrawGroups() const Standard_OVERRIDE
   { return myParent->DrawGroups(); }
 
+  //! Renders groups of parent structure.
+  virtual void renderGeometry (const Handle(OpenGl_Workspace)& theWorkspace,
+                               bool&                           theHasClosed) const Standard_OVERRIDE
+  {
+    myParent->renderGeometry (theWorkspace, theHasClosed);
+  }
+
+  //! Renders closed groups of parent structure.
+  virtual void renderClosedGeometry (const Handle(OpenGl_Workspace)& theWorkspace) const Standard_OVERRIDE
+  {
+    myParent->renderClosedGeometry (theWorkspace);
+  }
+
 private:
 
   Handle(OpenGl_Structure) myParent;

tests/bugs/vis/bug26940

@@ -0,0 +1,34 @@
+puts "============"
+puts "0026940: Visualization, TKOpenGl - capping plane should be applied to connected structures"
+puts "Tests capping plane rendering with connected structures"
+puts "============"
+puts ""
+
+vinit View1
+vclear
+vaxo
+vsetdispmode 1
+box b 1 1 1
+vdisplay b
+vfit
+
+vclipplane create pln
+vclipplane set pln view Driver1/Viewer1/View1
+vclipplane change pln equation 0 1 0 -0.5
+vclipplane change pln capping on
+
+vdump $imagedir/${casename}_normal.png
+set aColorNorm [vreadpixel 200 250 rgb name]
+if { "$aColorNorm" != "GRAY13" } {
+  puts "Error: Expected color of capping plane is GRAY13 (normal presentation). Actial is $aColorNorm"
+}
+
+vclear
+
+vconnectto bb 0 0 0 b
+vdump $imagedir/${casename}_connected.png
+set aColorConn [vreadpixel 200 250 rgb name]
+
+if { "$aColorConn" != "GRAY13" } {
+  puts "Error: Expected color of capping plane is GRAY13 (connected presentation). Actial is $aColorConn"
+}