[vtkusers] VisibleActorCount ...

[Kamran Iranpour]

Hi

I am very newbie in VTK and already having a few problems. I have
the following code:

----------start------------
	pointSet = vtkPolyData::New();
	freePoints = vtkPoints::New();
	zValues = vtkFloatArray::New();
	zValues->SetName("z values");


	for (int i = 0; i < n; i++) {
		pnt[0] = data[i*3];
		pnt[1] = data[i*3+1];
		pnt[2] = data[i*3+2];
		freePoints->InsertPoint(nPoints, pnt);
		zValues->InsertValue(nPoints, pnt[2]);
		nPoints++;
	}	

	pointSet->GetPointData()->SetScalars(zValues);
	zValues->Delete();
	pointSet->SetPoints(freePoints);
	QString caption = QString("Surface 1");
	previewWidget->setDataSet(pointSet);	// canvas subclass
        previewWidget->Render();	
        freePoints->Delete();		
	pointSet->Delete();

---------------end------------

I have a few thousands points  (xyz) which I correctly render
and everything is OK if I do that once. But If I chose another set of points
the rendering get slower and slower for a third time and so on.
I have cheked to see if I have a memory leakage somewhere but
I don't see any increase in memory use which makes it more strange
than I first thought.
Then I read something about  "VisibleActorCount" and "VisibleVolumeCount"
and checked these values and saw that they increase by three for each time
I render a new set of points.  So I used the following to remove these
each time I have new points to render:
-----------------start-----------------
  vtkActorCollection *actors = vtkActorCollection::New();
  int NumberOfActors = previewWidget->getRenderer()->VisibleActorCount();

  actors=previewWidget->getRenderer()->GetActors();
  actors->InitTraversal();
  for (int i=0; i<NumberOfActors; i++) {
     previewWidget->getRenderer()->RemoveActor(actors->GetNextActor());
  }
  actors->Delete();
----------------end-------------------
(and equally for Volumes)

But still the number of  of a visible actors and volumes keep increasing
and after a few times the whole thing crashes.

The question is,  am I doing the right thing, removing the actors and
volumes or not and why it keeps increasing.

Thanks in advance for your help

Kamran