[vtkusers] question about the vtkImagePlaneWidget demo in the vtk package

[kdsfinger at gmail.com]

hi, all

Here is the code of the vtkImagePlaneWidget demo in the vtk package
(with minimum change to make it shorter). My question is: How does the
vtkImagePlaneWidget add into the vtkRenderWindow ren1? ren1 nenver set
it. And if I don't creat ren1, then the vtkImagePlaneWidget will
automatically add into the ren2 window. What is the machanism to
control where the vtkImagePlaneWindow should add to? Thanks for
comments.

zl2k

/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: ImagePlaneWidget.cxx,v $

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "vtkActor.h"
#include "vtkCamera.h"
#include "vtkCellPicker.h"
#include "vtkCommand.h"
#include "vtkImageActor.h"
#include "vtkImageMapToColors.h"
#include "vtkImagePlaneWidget.h"
#include "vtkImageReader.h"
#include "vtkInteractorEventRecorder.h"
#include "vtkLookupTable.h"
#include "vtkOutlineFilter.h"
#include "vtkPolyDataMapper.h"
#include "vtkProperty.h"
#include "vtkRenderWindow.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkRenderer.h"
#include "vtkVolume16Reader.h"
#include "vtkImageData.h"

#include "vtkTestUtilities.h"
#include "vtkRegressionTestImage.h"
#include "vtkDebugLeaks.h"

#include <iostream.h>

using namespace std;


int main( int argc, char *argv[] )
{
  char* fname = "/home/me/vtk/VTKData/Data/headsq/quarter";

	
  vtkVolume16Reader* v16 =  vtkVolume16Reader::New();
    v16->SetDataDimensions( 64, 64);
    v16->SetDataByteOrderToLittleEndian();
    v16->SetImageRange( 1, 93);
    v16->SetDataSpacing( 3.2, 3.2, 1.5);
    v16->SetFilePrefix( fname );
    v16->SetDataMask( 0x7fff);
    v16->Update();
	
  vtkRenderer* ren1 = vtkRenderer::New();
  vtkRenderer* ren2 = vtkRenderer::New();

  vtkRenderWindow* renWin = vtkRenderWindow::New();
    renWin->AddRenderer(ren2);
    renWin->AddRenderer(ren1);// If I block this, the
vtkImagePlaneWidget will be automatically added to the ren2.

  vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();
    iren->SetRenderWindow(renWin);
	
  vtkCellPicker* picker = vtkCellPicker::New();
    picker->SetTolerance(0.005);

  vtkProperty* ipwProp = vtkProperty::New();
   //assign default props to the ipw's texture plane actor

  vtkImagePlaneWidget* planeWidgetX = vtkImagePlaneWidget::New();
    planeWidgetX->SetInteractor( iren);
    planeWidgetX->SetKeyPressActivationValue('x');
    planeWidgetX->SetPicker(picker);
    planeWidgetX->RestrictPlaneToVolumeOn();
    planeWidgetX->GetPlaneProperty()->SetColor(1,0,0);
    planeWidgetX->SetTexturePlaneProperty(ipwProp);
    planeWidgetX->TextureInterpolateOff();
    planeWidgetX->SetResliceInterpolateToNearestNeighbour();
    planeWidgetX->SetInput(v16->GetOutput());
    planeWidgetX->SetPlaneOrientationToXAxes();
    planeWidgetX->SetSliceIndex(32);
    planeWidgetX->DisplayTextOn();
    planeWidgetX->On();
    planeWidgetX->InteractionOff();
    planeWidgetX->InteractionOn();

  vtkImagePlaneWidget* planeWidgetY = vtkImagePlaneWidget::New();
    planeWidgetY->SetInteractor( iren);
    planeWidgetY->SetKeyPressActivationValue('y');
    planeWidgetY->SetPicker(picker);
    planeWidgetY->GetPlaneProperty()->SetColor(1,1,0);
    planeWidgetY->SetTexturePlaneProperty(ipwProp);
    planeWidgetY->TextureInterpolateOn();
    planeWidgetY->SetResliceInterpolateToLinear();
    planeWidgetY->SetInput(v16->GetOutput());
    planeWidgetY->SetPlaneOrientationToYAxes();
    planeWidgetY->SetSlicePosition(102.4);
    planeWidgetY->SetLookupTable( planeWidgetX->GetLookupTable());
    planeWidgetY->DisplayTextOff();
    planeWidgetY->UpdatePlacement();
    planeWidgetY->On();

  vtkImagePlaneWidget* planeWidgetZ = vtkImagePlaneWidget::New();
    planeWidgetZ->SetInteractor( iren);
    planeWidgetZ->SetKeyPressActivationValue('z');
    planeWidgetZ->SetPicker(picker);
    planeWidgetZ->GetPlaneProperty()->SetColor(0,0,1);
    planeWidgetZ->SetTexturePlaneProperty(ipwProp);
    planeWidgetZ->TextureInterpolateOn();
    planeWidgetZ->SetResliceInterpolateToCubic();
    planeWidgetZ->SetInput(v16->GetOutput());
    planeWidgetZ->SetPlaneOrientationToZAxes();
    planeWidgetZ->SetSliceIndex(25);
    planeWidgetZ->SetLookupTable( planeWidgetX->GetLookupTable());
    planeWidgetZ->DisplayTextOn();
    planeWidgetZ->On();

  double wl[2];
  planeWidgetZ->GetWindowLevel(wl);

  // Add a 2D image to test the GetReslice method
  //

  vtkImageMapToColors* colorMap = vtkImageMapToColors::New();
    colorMap->PassAlphaToOutputOff();
    colorMap->SetActiveComponent(0);
    colorMap->SetOutputFormatToLuminance();
    colorMap->SetInput(planeWidgetZ->GetResliceOutput());
    colorMap->SetLookupTable(planeWidgetX->GetLookupTable());

  vtkImageActor* imageActor = vtkImageActor::New();
    imageActor->PickableOff();
    imageActor->SetInput(colorMap->GetOutput());
	
  // Add the actors
  //
  //ren1->AddActor( outlineActor);
  ren2->AddActor( imageActor);

  ren1->SetBackground( 0.1, 0.1, 0.3);
  ren2->SetBackground( 0.2, 0.1, 0.2);

  renWin->SetSize( 300, 300);

  ren1->SetViewport(0,0,0.65,1);
  ren2->SetViewport(0.65,0,1,1);

  // Set the actors' postions
  //

  renWin->Render();

  iren->SetEventPosition( 475,175);
  iren->SetKeyCode('r');
  iren->InvokeEvent(vtkCommand::CharEvent,NULL);
  renWin->Render();
	
  iren->Initialize();
  renWin->Render();

  iren->Start();
  	
  ipwProp->Delete();
  planeWidgetX->Delete();
  planeWidgetY->Delete();
  planeWidgetZ->Delete();
  colorMap->Delete();
  imageActor->Delete();
  picker->Delete();
  iren->Delete();
  renWin->Delete();
  ren1->Delete();
  ren2->Delete();
  v16->Delete();

  return 0;
}