vtkPlaneWidget.cxx

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

  Program:   Visualization Toolkit
  Module:    vtkPlaneWidget.cxx

  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 "vtkPlaneWidget.h"

#include "vtkActor.h"
#include "vtkAssemblyNode.h"
#include "vtkAssemblyPath.h"
#include "vtkCallbackCommand.h"
#include "vtkCamera.h"
#include "vtkCellArray.h"
#include "vtkCellPicker.h"
#include "vtkConeSource.h"
#include "vtkDoubleArray.h"
#include "vtkFloatArray.h"
#include "vtkLineSource.h"
#include "vtkMath.h"
#include "vtkObjectFactory.h"
#include "vtkPickingManager.h"
#include "vtkPlane.h"
#include "vtkPlaneSource.h"
#include "vtkPlanes.h"
#include "vtkPolyData.h"
#include "vtkPolyDataMapper.h"
#include "vtkProperty.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkRenderer.h"
#include "vtkSphereSource.h"
#include "vtkTransform.h"

vtkStandardNewMacro(vtkPlaneWidget);

vtkCxxSetObjectMacro(vtkPlaneWidget,PlaneProperty,vtkProperty);

vtkPlaneWidget::vtkPlaneWidget() : vtkPolyDataSourceWidget()
{
  this->State = vtkPlaneWidget::Start;
  this->EventCallbackCommand->SetCallback(vtkPlaneWidget::ProcessEvents);

  this->NormalToXAxis = 0;
  this->NormalToYAxis = 0;
  this->NormalToZAxis = 0;
  this->Representation = VTK_PLANE_WIREFRAME;

  //Build the representation of the widget
  int i;
  // Represent the plane
  this->PlaneSource = vtkPlaneSource::New();
  this->PlaneSource->SetXResolution(4);
  this->PlaneSource->SetYResolution(4);
  this->PlaneOutline = vtkPolyData::New();
  vtkPoints *pts = vtkPoints::New();
  pts->SetNumberOfPoints(4);
  vtkCellArray *outline = vtkCellArray::New();
  outline->InsertNextCell(4);
  outline->InsertCellPoint(0);
  outline->InsertCellPoint(1);
  outline->InsertCellPoint(2);
  outline->InsertCellPoint(3);
  this->PlaneOutline->SetPoints(pts);
  pts->Delete();
  this->PlaneOutline->SetPolys(outline);
  outline->Delete();
  this->PlaneMapper = vtkPolyDataMapper::New();
  this->PlaneMapper->SetInputConnection(
    this->PlaneSource->GetOutputPort());
  this->PlaneActor = vtkActor::New();
  this->PlaneActor->SetMapper(this->PlaneMapper);

  // Create the handles
  this->Handle = new vtkActor* [4];
  this->HandleMapper = new vtkPolyDataMapper* [4];
  this->HandleGeometry = new vtkSphereSource* [4];
  for (i=0; i<4; i++)
  {
    this->HandleGeometry[i] = vtkSphereSource::New();
    this->HandleGeometry[i]->SetThetaResolution(16);
    this->HandleGeometry[i]->SetPhiResolution(8);
    this->HandleMapper[i] = vtkPolyDataMapper::New();
    this->HandleMapper[i]->SetInputConnection(
      this->HandleGeometry[i]->GetOutputPort());
    this->Handle[i] = vtkActor::New();
    this->Handle[i]->SetMapper(this->HandleMapper[i]);
  }

  // Create the + plane normal
  this->LineSource = vtkLineSource::New();
  this->LineSource->SetResolution(1);
  this->LineMapper = vtkPolyDataMapper::New();
  this->LineMapper->SetInputConnection(
    this->LineSource->GetOutputPort());
  this->LineActor = vtkActor::New();
  this->LineActor->SetMapper(this->LineMapper);

  this->ConeSource = vtkConeSource::New();
  this->ConeSource->SetResolution(12);
  this->ConeSource->SetAngle(25.0);
  this->ConeMapper = vtkPolyDataMapper::New();
  this->ConeMapper->SetInputConnection(
    this->ConeSource->GetOutputPort());
  this->ConeActor = vtkActor::New();
  this->ConeActor->SetMapper(this->ConeMapper);

  // Create the - plane normal
  this->LineSource2 = vtkLineSource::New();
  this->LineSource2->SetResolution(1);
  this->LineMapper2 = vtkPolyDataMapper::New();
  this->LineMapper2->SetInputConnection(
    this->LineSource2->GetOutputPort());
  this->LineActor2 = vtkActor::New();
  this->LineActor2->SetMapper(this->LineMapper2);

  this->ConeSource2 = vtkConeSource::New();
  this->ConeSource2->SetResolution(12);
  this->ConeSource2->SetAngle(25.0);
  this->ConeMapper2 = vtkPolyDataMapper::New();
  this->ConeMapper2->SetInputConnection(
    this->ConeSource2->GetOutputPort());
  this->ConeActor2 = vtkActor::New();
  this->ConeActor2->SetMapper(this->ConeMapper2);

  this->Transform = vtkTransform::New();

  // Define the point coordinates
  double bounds[6];
  bounds[0] = -0.5;
  bounds[1] = 0.5;
  bounds[2] = -0.5;
  bounds[3] = 0.5;
  bounds[4] = -0.5;
  bounds[5] = 0.5;

  //Manage the picking stuff
  this->HandlePicker = vtkCellPicker::New();
  this->HandlePicker->SetTolerance(0.001);
  for (i=0; i<4; i++)
  {
    this->HandlePicker->AddPickList(this->Handle[i]);
  }
  this->HandlePicker->PickFromListOn();

  this->PlanePicker = vtkCellPicker::New();
  this->PlanePicker->SetTolerance(0.005); //need some fluff
  this->PlanePicker->AddPickList(this->PlaneActor);
  this->PlanePicker->AddPickList(this->ConeActor);
  this->PlanePicker->AddPickList(this->LineActor);
  this->PlanePicker->AddPickList(this->ConeActor2);
  this->PlanePicker->AddPickList(this->LineActor2);
  this->PlanePicker->PickFromListOn();

  this->CurrentHandle = NULL;

  this->LastPickValid = 0;
  this->HandleSizeFactor = 1.25;
  this->SetHandleSize( 0.05 );

  // Set up the initial properties
  this->CreateDefaultProperties();

  this->SelectRepresentation();

  // Initial creation of the widget, serves to initialize it
  // Call PlaceWidget() LAST in the constructor as it depends on ivar
  // values.
  this->PlaceWidget(bounds);
}

vtkPlaneWidget::~vtkPlaneWidget()
{
  this->PlaneActor->Delete();
  this->PlaneMapper->Delete();
  this->PlaneSource->Delete();
  this->PlaneOutline->Delete();

  for (int i=0; i<4; i++)
  {
    this->HandleGeometry[i]->Delete();
    this->HandleMapper[i]->Delete();
    this->Handle[i]->Delete();
  }
  delete [] this->Handle;
  delete [] this->HandleMapper;
  delete [] this->HandleGeometry;

  this->ConeActor->Delete();
  this->ConeMapper->Delete();
  this->ConeSource->Delete();

  this->LineActor->Delete();
  this->LineMapper->Delete();
  this->LineSource->Delete();

  this->ConeActor2->Delete();
  this->ConeMapper2->Delete();
  this->ConeSource2->Delete();

  this->LineActor2->Delete();
  this->LineMapper2->Delete();
  this->LineSource2->Delete();

  this->HandlePicker->Delete();
  this->PlanePicker->Delete();

  if (this->HandleProperty)
  {
    this->HandleProperty->Delete();
    this->HandleProperty = 0;
  }

  if (this->SelectedHandleProperty)
  {
    this->SelectedHandleProperty->Delete();
    this->SelectedHandleProperty = 0;
  }

  if (this->PlaneProperty)
  {
    this->PlaneProperty->Delete();
    this->PlaneProperty = 0;
  }

  if (this->SelectedPlaneProperty)
  {
    this->SelectedPlaneProperty->Delete();
    this->SelectedPlaneProperty = 0;
  }

  this->Transform->Delete();
}

void vtkPlaneWidget::SetEnabled(int enabling)
{
  if ( ! this->Interactor )
  {
    vtkErrorMacro(<<"The interactor must be set prior to enabling/disabling widget");
    return;
  }

  if ( enabling ) //-----------------------------------------------------------
  {
    vtkDebugMacro(<<"Enabling plane widget");

    if ( this->Enabled ) //already enabled, just return
    {
      return;
    }

    if ( ! this->CurrentRenderer )
    {
      this->SetCurrentRenderer(this->Interactor->FindPokedRenderer(
        this->Interactor->GetLastEventPosition()[0],
        this->Interactor->GetLastEventPosition()[1]));
      if (this->CurrentRenderer == NULL)
      {
        return;
      }
    }

    this->Enabled = 1;

    // listen for the following events
    vtkRenderWindowInteractor *i = this->Interactor;
    i->AddObserver(vtkCommand::MouseMoveEvent, this->EventCallbackCommand,
                   this->Priority);
    i->AddObserver(vtkCommand::LeftButtonPressEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::LeftButtonReleaseEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::MiddleButtonPressEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::MiddleButtonReleaseEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::RightButtonPressEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::RightButtonReleaseEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::StartPinchEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::PinchEvent,
                   this->EventCallbackCommand, this->Priority);
    i->AddObserver(vtkCommand::EndPinchEvent,
                   this->EventCallbackCommand, this->Priority);

    // Add the plane
    this->CurrentRenderer->AddActor(this->PlaneActor);
    this->PlaneActor->SetProperty(this->PlaneProperty);

    // turn on the handles
    for (int j=0; j<4; j++)
    {
      this->CurrentRenderer->AddActor(this->Handle[j]);
      this->Handle[j]->SetProperty(this->HandleProperty);
    }

    // add the normal vector
    this->CurrentRenderer->AddActor(this->LineActor);
    this->LineActor->SetProperty(this->HandleProperty);
    this->CurrentRenderer->AddActor(this->ConeActor);
    this->ConeActor->SetProperty(this->HandleProperty);
    this->CurrentRenderer->AddActor(this->LineActor2);
    this->LineActor2->SetProperty(this->HandleProperty);
    this->CurrentRenderer->AddActor(this->ConeActor2);
    this->ConeActor2->SetProperty(this->HandleProperty);

    this->SelectRepresentation();
    this->InvokeEvent(vtkCommand::EnableEvent,NULL);
  }

  else //disabling----------------------------------------------------------
  {
    vtkDebugMacro(<<"Disabling plane widget");

    if ( ! this->Enabled ) //already disabled, just return
    {
      return;
    }

    this->Enabled = 0;

    // don't listen for events any more
    this->Interactor->RemoveObserver(this->EventCallbackCommand);

    // turn off the plane
    this->CurrentRenderer->RemoveActor(this->PlaneActor);

    // turn off the handles
    for (int i=0; i<4; i++)
    {
      this->CurrentRenderer->RemoveActor(this->Handle[i]);
    }

    // turn off the normal vector
    this->CurrentRenderer->RemoveActor(this->LineActor);
    this->CurrentRenderer->RemoveActor(this->ConeActor);
    this->CurrentRenderer->RemoveActor(this->LineActor2);
    this->CurrentRenderer->RemoveActor(this->ConeActor2);

    this->CurrentHandle = NULL;
    this->InvokeEvent(vtkCommand::DisableEvent,NULL);
    this->SetCurrentRenderer(NULL);
  }

  this->Interactor->Render();
}

//------------------------------------------------------------------------------
void vtkPlaneWidget::RegisterPickers()
{
  this->Interactor->GetPickingManager()->AddPicker(this->HandlePicker, this);
  this->Interactor->GetPickingManager()->AddPicker(this->PlanePicker, this);
}

void vtkPlaneWidget::ProcessEvents(vtkObject* vtkNotUsed(object),
                                   unsigned long event,
                                   void* clientdata,
                                   void* vtkNotUsed(calldata))
{
  vtkPlaneWidget* self = reinterpret_cast<vtkPlaneWidget *>( clientdata );

  //okay, let's do the right thing
  switch(event)
  {
    case vtkCommand::LeftButtonPressEvent:
      self->OnLeftButtonDown();
      break;
    case vtkCommand::LeftButtonReleaseEvent:
      self->OnLeftButtonUp();
      break;
    case vtkCommand::MiddleButtonPressEvent:
      self->OnMiddleButtonDown();
      break;
    case vtkCommand::MiddleButtonReleaseEvent:
      self->OnMiddleButtonUp();
      break;
    case vtkCommand::RightButtonPressEvent:
      self->OnRightButtonDown();
      break;
    case vtkCommand::RightButtonReleaseEvent:
      self->OnRightButtonUp();
      break;
    case vtkCommand::MouseMoveEvent:
      self->OnMouseMove();
      break;
    case vtkCommand::StartPinchEvent:
      self->OnStartPinch();
      break;
    case vtkCommand::PinchEvent:
      self->OnPinch();
      break;
    case vtkCommand::EndPinchEvent:
      self->OnEndPinch();
      break;
  }
}

void vtkPlaneWidget::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);

  if ( this->HandleProperty )
  {
    os << indent << "Handle Property: " << this->HandleProperty << "\n";
  }
  else
  {
    os << indent << "Handle Property: (none)\n";
  }
  if ( this->SelectedHandleProperty )
  {
    os << indent << "Selected Handle Property: "
       << this->SelectedHandleProperty << "\n";
  }
  else
  {
    os << indent << "SelectedHandle Property: (none)\n";
  }

  if ( this->PlaneProperty )
  {
    os << indent << "Plane Property: " << this->PlaneProperty << "\n";
  }
  else
  {
    os << indent << "Plane Property: (none)\n";
  }
  if ( this->SelectedPlaneProperty )
  {
    os << indent << "Selected Plane Property: "
       << this->SelectedPlaneProperty << "\n";
  }
  else
  {
    os << indent << "Selected Plane Property: (none)\n";
  }

  os << indent << "Plane Representation: ";
  if ( this->Representation == VTK_PLANE_WIREFRAME )
  {
    os << "Wireframe\n";
  }
  else if ( this->Representation == VTK_PLANE_SURFACE )
  {
    os << "Surface\n";
  }
  else //( this->Representation == VTK_PLANE_OUTLINE )
  {
    os << "Outline\n";
  }

  os << indent << "Normal To X Axis: "
     << (this->NormalToXAxis ? "On" : "Off") << "\n";
  os << indent << "Normal To Y Axis: "
     << (this->NormalToYAxis ? "On" : "Off") << "\n";
  os << indent << "Normal To Z Axis: "
     << (this->NormalToZAxis ? "On" : "Off") << "\n";

  int res = this->PlaneSource->GetXResolution();
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  os << indent << "Resolution: " << res << "\n";
  os << indent << "Origin: (" << o[0] << ", "
     << o[1] << ", "
     << o[2] << ")\n";
  os << indent << "Point 1: (" << pt1[0] << ", "
     << pt1[1] << ", "
     << pt1[2] << ")\n";
  os << indent << "Point 2: (" << pt2[0] << ", "
     << pt2[1] << ", "
     << pt2[2] << ")\n";
}

void vtkPlaneWidget::PositionHandles()
{
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  this->HandleGeometry[0]->SetCenter(o);
  this->HandleGeometry[1]->SetCenter(pt1);
  this->HandleGeometry[2]->SetCenter(pt2);

  double x[3];
  x[0] = pt1[0] + pt2[0] - o[0];
  x[1] = pt1[1] + pt2[1] - o[1];
  x[2] = pt1[2] + pt2[2] - o[2];
  this->HandleGeometry[3]->SetCenter(x); //far corner

  // set up the outline
  if ( this->Representation == VTK_PLANE_OUTLINE )
  {
    this->PlaneOutline->GetPoints()->SetPoint(0,o);
    this->PlaneOutline->GetPoints()->SetPoint(1,pt1);
    this->PlaneOutline->GetPoints()->SetPoint(2,x);
    this->PlaneOutline->GetPoints()->SetPoint(3,pt2);
    this->PlaneOutline->Modified();
  }
  this->SelectRepresentation();

  // Create the normal vector
  double center[3];
  this->PlaneSource->GetCenter(center);
  this->LineSource->SetPoint1(center);
  this->LineSource2->SetPoint1(center);
  double p2[3];
  this->PlaneSource->GetNormal(this->Normal);
  vtkMath::Normalize(this->Normal);
  double d = sqrt(
    vtkMath::Distance2BetweenPoints(
      this->PlaneSource->GetPoint1(),this->PlaneSource->GetPoint2()) );

  p2[0] = center[0] + 0.35 * d * this->Normal[0];
  p2[1] = center[1] + 0.35 * d * this->Normal[1];
  p2[2] = center[2] + 0.35 * d * this->Normal[2];
  this->LineSource->SetPoint2(p2);
  this->ConeSource->SetCenter(p2);
  this->ConeSource->SetDirection(this->Normal);

  p2[0] = center[0] - 0.35 * d * this->Normal[0];
  p2[1] = center[1] - 0.35 * d * this->Normal[1];
  p2[2] = center[2] - 0.35 * d * this->Normal[2];
  this->LineSource2->SetPoint2(p2);
  this->ConeSource2->SetCenter(p2);
  this->ConeSource2->SetDirection(this->Normal);
}

int vtkPlaneWidget::HighlightHandle(vtkProp *prop)
{
  // first unhighlight anything picked
  if ( this->CurrentHandle )
  {
    this->CurrentHandle->SetProperty(this->HandleProperty);
  }

  this->CurrentHandle = static_cast<vtkActor *>(prop);

  if ( this->CurrentHandle )
  {
    this->ValidPick = 1;
    this->HandlePicker->GetPickPosition(this->LastPickPosition);
    this->CurrentHandle->SetProperty(this->SelectedHandleProperty);
    for (int i=0; i<4; i++) //find handle
    {
      if ( this->CurrentHandle == this->Handle[i] )
      {
        return i;
      }
    }
  }

  return -1;
}

void vtkPlaneWidget::HighlightNormal(int highlight)
{
  if ( highlight )
  {
    this->ValidPick = 1;
    this->PlanePicker->GetPickPosition(this->LastPickPosition);
    this->LineActor->SetProperty(this->SelectedHandleProperty);
    this->ConeActor->SetProperty(this->SelectedHandleProperty);
    this->LineActor2->SetProperty(this->SelectedHandleProperty);
    this->ConeActor2->SetProperty(this->SelectedHandleProperty);
  }
  else
  {
    this->LineActor->SetProperty(this->HandleProperty);
    this->ConeActor->SetProperty(this->HandleProperty);
    this->LineActor2->SetProperty(this->HandleProperty);
    this->ConeActor2->SetProperty(this->HandleProperty);
  }
}

void vtkPlaneWidget::HighlightPlane(int highlight)
{
  if ( highlight )
  {
    this->ValidPick = 1;
    this->PlanePicker->GetPickPosition(this->LastPickPosition);
    this->PlaneActor->SetProperty(this->SelectedPlaneProperty);
  }
  else
  {
    this->PlaneActor->SetProperty(this->PlaneProperty);
  }
}

void vtkPlaneWidget::OnStartPinch()
{
  int X = this->Interactor->GetEventPosition()[0];
  int Y = this->Interactor->GetEventPosition()[1];

  // Okay, make sure that the pick is in the current renderer
  if (!this->CurrentRenderer || !this->CurrentRenderer->IsInViewport(X, Y))
  {
    this->State = vtkPlaneWidget::Outside;
    return;
  }

  // Okay, we can process this. try to pick the plane.
  vtkAssemblyPath* path = this->GetAssemblyPath(X, Y, 0., this->PlanePicker);

  if ( path != NULL )
  {
    this->State = vtkPlaneWidget::Pinching;
    this->HighlightPlane(1);
    this->StartInteraction();
    this->InvokeEvent(vtkCommand::StartInteractionEvent,NULL);
  }
}

void vtkPlaneWidget::OnPinch()
{
  if ( this->State != vtkPlaneWidget::Pinching)
  {
    return;
  }

  double sf = this->Interactor->GetScale()/this->Interactor->GetLastScale();
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  double center[3];
  center[0] = 0.5 * ( pt1[0] + pt2[0] );
  center[1] = 0.5 * ( pt1[1] + pt2[1] );
  center[2] = 0.5 * ( pt1[2] + pt2[2] );

  // Move the corner points
  double origin[3], point1[3], point2[3];
  for (int i=0; i<3; i++)
  {
    origin[i] = sf * (o[i] - center[i]) + center[i];
    point1[i] = sf * (pt1[i] - center[i]) + center[i];
    point2[i] = sf * (pt2[i] - center[i]) + center[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();

  this->EventCallbackCommand->SetAbortFlag(1);
  this->InvokeEvent(vtkCommand::InteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnEndPinch()
{
  if ( this->State != vtkPlaneWidget::Pinching)
  {
    return;
  }

  this->State = vtkPlaneWidget::Start;
  this->HighlightHandle(NULL);
  this->HighlightPlane(0);
  this->HighlightNormal(0);
  this->SizeHandles();

  this->EventCallbackCommand->SetAbortFlag(1);
  this->EndInteraction();
  this->InvokeEvent(vtkCommand::EndInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnLeftButtonDown()
{
  int X = this->Interactor->GetEventPosition()[0];
  int Y = this->Interactor->GetEventPosition()[1];

  // Okay, make sure that the pick is in the current renderer
  if (!this->CurrentRenderer || !this->CurrentRenderer->IsInViewport(X, Y))
  {
    this->State = vtkPlaneWidget::Outside;
    return;
  }

  // Okay, we can process this. Try to pick handles first;
  // if no handles picked, then try to pick the plane.
  vtkAssemblyPath* path = this->GetAssemblyPath(X, Y, 0., this->HandlePicker);

  if ( path != NULL )
  {
    this->State = vtkPlaneWidget::Moving;
    this->HighlightHandle(path->GetFirstNode()->GetViewProp());
  }
  else
  {
    path = this->GetAssemblyPath(X, Y, 0., this->PlanePicker);

    if ( path != NULL )
    {
      vtkProp *prop = path->GetFirstNode()->GetViewProp();
      if ( prop == this->ConeActor || prop == this->LineActor ||
           prop == this->ConeActor2 || prop == this->LineActor2 )
      {
        this->State = vtkPlaneWidget::Rotating;
        this->HighlightNormal(1);
      }
      else if (this->Interactor->GetControlKey())
      {
        this->State = vtkPlaneWidget::Spinning;
        this->HighlightNormal(1);
      }
      else
      {
        this->State = vtkPlaneWidget::Moving;
        this->HighlightPlane(1);
      }
    }
    else
    {
      this->State = vtkPlaneWidget::Outside;
      this->HighlightHandle(NULL);
      return;
    }
  }

  this->EventCallbackCommand->SetAbortFlag(1);
  this->StartInteraction();
  this->InvokeEvent(vtkCommand::StartInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnLeftButtonUp()
{
  if ( this->State == vtkPlaneWidget::Outside ||
       this->State == vtkPlaneWidget::Start )
  {
    return;
  }

  this->State = vtkPlaneWidget::Start;
  this->HighlightHandle(NULL);
  this->HighlightPlane(0);
  this->HighlightNormal(0);
  this->SizeHandles();

  this->EventCallbackCommand->SetAbortFlag(1);
  this->EndInteraction();
  this->InvokeEvent(vtkCommand::EndInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnMiddleButtonDown()
{
  int X = this->Interactor->GetEventPosition()[0];
  int Y = this->Interactor->GetEventPosition()[1];

  // Okay, make sure that the pick is in the current renderer
  if (!this->CurrentRenderer || !this->CurrentRenderer->IsInViewport(X, Y))
  {
    this->State = vtkPlaneWidget::Outside;
    return;
  }

  // Okay, we can process this. If anything is picked, then we
  // can start pushing the plane.
  vtkAssemblyPath* path = this->GetAssemblyPath(X, Y, 0., this->HandlePicker);

  if ( path != NULL )
  {
    this->State = vtkPlaneWidget::Pushing;
    this->HighlightPlane(1);
    this->HighlightNormal(1);
    this->HighlightHandle(path->GetFirstNode()->GetViewProp());
  }
  else
  {
    path = this->GetAssemblyPath(X, Y, 0., this->PlanePicker);

    if ( path == NULL ) //nothing picked
    {
      this->State = vtkPlaneWidget::Outside;
      return;
    }
    else
    {
      this->State = vtkPlaneWidget::Pushing;
      this->HighlightNormal(1);
      this->HighlightPlane(1);
    }
  }

  this->EventCallbackCommand->SetAbortFlag(1);
  this->StartInteraction();
  this->InvokeEvent(vtkCommand::StartInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnMiddleButtonUp()
{
  if ( this->State == vtkPlaneWidget::Outside ||
       this->State == vtkPlaneWidget::Start )
  {
    return;
  }

  this->State = vtkPlaneWidget::Start;
  this->HighlightPlane(0);
  this->HighlightNormal(0);
  this->HighlightHandle(NULL);
  this->SizeHandles();

  this->EventCallbackCommand->SetAbortFlag(1);
  this->EndInteraction();
  this->InvokeEvent(vtkCommand::EndInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnRightButtonDown()
{
  int X = this->Interactor->GetEventPosition()[0];
  int Y = this->Interactor->GetEventPosition()[1];

  // Okay, make sure that the pick is in the current renderer
  if (!this->CurrentRenderer || !this->CurrentRenderer->IsInViewport(X, Y))
  {
    this->State = vtkPlaneWidget::Outside;
    return;
  }

  // Okay, we can process this. Try to pick handles first;
  // if no handles picked, then pick the bounding box.
  vtkAssemblyPath* path = this->GetAssemblyPath(X, Y, 0., this->HandlePicker);

  if ( path != NULL )
  {
    this->State = vtkPlaneWidget::Scaling;
    this->HighlightPlane(1);
    this->HighlightHandle(path->GetFirstNode()->GetViewProp());
  }
  else //see if we picked the plane or a normal
  {
    path = this->GetAssemblyPath(X, Y, 0., this->PlanePicker);

    if ( path == NULL )
    {
      this->State = vtkPlaneWidget::Outside;
      return;
    }
    else
    {
      this->State = vtkPlaneWidget::Scaling;
      this->HighlightPlane(1);
    }
  }

  this->EventCallbackCommand->SetAbortFlag(1);
  this->StartInteraction();
  this->InvokeEvent(vtkCommand::StartInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnRightButtonUp()
{
  if ( this->State == vtkPlaneWidget::Outside ||
       this->State == vtkPlaneWidget::Start )
  {
    return;
  }

  this->State = vtkPlaneWidget::Start;
  this->HighlightPlane(0);
  this->SizeHandles();

  this->EventCallbackCommand->SetAbortFlag(1);
  this->EndInteraction();
  this->InvokeEvent(vtkCommand::EndInteractionEvent,NULL);
  this->Interactor->Render();
}

void vtkPlaneWidget::OnMouseMove()
{
  // See whether we're active
  if ( this->State == vtkPlaneWidget::Outside ||
       this->State == vtkPlaneWidget::Start )
  {
    return;
  }

  int X = this->Interactor->GetEventPosition()[0];
  int Y = this->Interactor->GetEventPosition()[1];

  // Do different things depending on state
  // Calculations everybody does
  double focalPoint[4], pickPoint[4], prevPickPoint[4];
  double z, vpn[3];

  vtkCamera *camera = this->CurrentRenderer->GetActiveCamera();
  if ( !camera )
  {
    return;
  }

  // Compute the two points defining the motion vector
  this->ComputeWorldToDisplay(this->LastPickPosition[0],
                              this->LastPickPosition[1],
                              this->LastPickPosition[2], focalPoint);
  z = focalPoint[2];
  this->ComputeDisplayToWorld(
    double(this->Interactor->GetLastEventPosition()[0]),
    double(this->Interactor->GetLastEventPosition()[1]),
    z, prevPickPoint);
  this->ComputeDisplayToWorld(double(X), double(Y), z, pickPoint);

  // Process the motion
  if ( this->State == vtkPlaneWidget::Moving )
  {
    // Okay to process
    if ( this->CurrentHandle )
    {
      if ( this->CurrentHandle == this->Handle[0] )
      {
        this->MoveOrigin(prevPickPoint, pickPoint);
      }
      else if ( this->CurrentHandle == this->Handle[1] )
      {
        this->MovePoint1(prevPickPoint, pickPoint);
      }
      else if ( this->CurrentHandle == this->Handle[2] )
      {
        this->MovePoint2(prevPickPoint, pickPoint);
      }
      else if ( this->CurrentHandle == this->Handle[3] )
      {
        this->MovePoint3(prevPickPoint, pickPoint);
      }
    }
    else //must be moving the plane
    {
      this->Translate(prevPickPoint, pickPoint);
    }
  }
  else if ( this->State == vtkPlaneWidget::Scaling )
  {
    this->Scale(prevPickPoint, pickPoint, X, Y);
  }
  else if ( this->State == vtkPlaneWidget::Pushing )
  {
    this->Push(prevPickPoint, pickPoint);
  }
  else if ( this->State == vtkPlaneWidget::Rotating )
  {
    camera->GetViewPlaneNormal(vpn);
    this->Rotate(X, Y, prevPickPoint, pickPoint, vpn);
  }
  else if ( this->State == vtkPlaneWidget::Spinning )
  {
    this->Spin(prevPickPoint, pickPoint);
  }


  // Interact, if desired
  this->EventCallbackCommand->SetAbortFlag(1);
  this->InvokeEvent(vtkCommand::InteractionEvent,NULL);

  this->Interactor->Render();
}

void vtkPlaneWidget::MoveOrigin(double *p1, double *p2)
{
  //Get the plane definition
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  //Get the vector of motion
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  // The point opposite the origin (pt3) stays fixed
  double pt3[3];
  pt3[0] = o[0] + (pt1[0] - o[0]) + (pt2[0] - o[0]);
  pt3[1] = o[1] + (pt1[1] - o[1]) + (pt2[1] - o[1]);
  pt3[2] = o[2] + (pt1[2] - o[2]) + (pt2[2] - o[2]);

  // Define vectors from point pt3
  double p13[3], p23[3];
  p13[0] = pt1[0] - pt3[0];
  p13[1] = pt1[1] - pt3[1];
  p13[2] = pt1[2] - pt3[2];
  p23[0] = pt2[0] - pt3[0];
  p23[1] = pt2[1] - pt3[1];
  p23[2] = pt2[2] - pt3[2];

  double vN = vtkMath::Norm(v);
  double n13 = vtkMath::Norm(p13);
  double n23 = vtkMath::Norm(p23);

  // Project v onto these vector to determine the amount of motion
  // Scale it by the relative size of the motion to the vector length
  double d1 = (vN/n13) * vtkMath::Dot(v,p13) / (vN*n13);
  double d2 = (vN/n23) * vtkMath::Dot(v,p23) / (vN*n23);

  double point1[3], point2[3], origin[3];
  for (int i=0; i<3; i++)
  {
    point1[i] = pt3[i] + (1.0+d1)*p13[i];
    point2[i] = pt3[i] + (1.0+d2)*p23[i];
    origin[i] = pt3[i] + (1.0+d1)*p13[i] + (1.0+d2)*p23[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::MovePoint1(double *p1, double *p2)
{
  //Get the plane definition
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  //Get the vector of motion
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  // Need the point opposite the origin (pt3)
  double pt3[3];
  pt3[0] = o[0] + (pt1[0] - o[0]) + (pt2[0] - o[0]);
  pt3[1] = o[1] + (pt1[1] - o[1]) + (pt2[1] - o[1]);
  pt3[2] = o[2] + (pt1[2] - o[2]) + (pt2[2] - o[2]);

  // Define vectors from point pt2
  double p32[3], p02[3];
  p02[0] = o[0] - pt2[0];
  p02[1] = o[1] - pt2[1];
  p02[2] = o[2] - pt2[2];
  p32[0] = pt3[0] - pt2[0];
  p32[1] = pt3[1] - pt2[1];
  p32[2] = pt3[2] - pt2[2];

  double vN = vtkMath::Norm(v);
  double n02 = vtkMath::Norm(p02);
  double n32 = vtkMath::Norm(p32);

  // if there is no motion then return
  if (vN == 0.0)
  {
    return;
  }

  // Project v onto these vector to determine the amount of motion
  // Scale it by the relative size of the motion to the vector length
  double d1 = (vN/n02) * vtkMath::Dot(v,p02) / (vN*n02);
  double d2 = (vN/n32) * vtkMath::Dot(v,p32) / (vN*n32);

  double point1[3], origin[3];
  for (int i=0; i<3; i++)
  {
    origin[i] = pt2[i] + (1.0+d1)*p02[i];
    point1[i] = pt2[i] + (1.0+d1)*p02[i] + (1.0+d2)*p32[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::MovePoint2(double *p1, double *p2)
{
  //Get the plane definition
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  //Get the vector of motion
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  // The point opposite point2 (pt1) stays fixed
  double pt3[3];
  pt3[0] = o[0] + (pt1[0] - o[0]) + (pt2[0] - o[0]);
  pt3[1] = o[1] + (pt1[1] - o[1]) + (pt2[1] - o[1]);
  pt3[2] = o[2] + (pt1[2] - o[2]) + (pt2[2] - o[2]);

  // Define vectors from point pt1
  double p01[3], p31[3];
  p31[0] = pt3[0] - pt1[0];
  p31[1] = pt3[1] - pt1[1];
  p31[2] = pt3[2] - pt1[2];
  p01[0] = o[0] - pt1[0];
  p01[1] = o[1] - pt1[1];
  p01[2] = o[2] - pt1[2];

  double vN = vtkMath::Norm(v);
  double n31 = vtkMath::Norm(p31);
  double n01 = vtkMath::Norm(p01);

  // if there is no motion then return
  if (vN == 0.0)
  {
    return;
  }

  // Project v onto these vector to determine the amount of motion
  // Scale it by the relative size of the motion to the vector length
  double d1 = (vN/n31) * vtkMath::Dot(v,p31) / (vN*n31);
  double d2 = (vN/n01) * vtkMath::Dot(v,p01) / (vN*n01);

  double point2[3], origin[3];
  for (int i=0; i<3; i++)
  {
    point2[i] = pt1[i] + (1.0+d1)*p31[i] + (1.0+d2)*p01[i];
    origin[i] = pt1[i] + (1.0+d2)*p01[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::MovePoint3(double *p1, double *p2)
{
  //Get the plane definition
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  //Get the vector of motion
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  // Define vectors from point pt3
  double p10[3], p20[3];
  p10[0] = pt1[0] - o[0];
  p10[1] = pt1[1] - o[1];
  p10[2] = pt1[2] - o[2];
  p20[0] = pt2[0] - o[0];
  p20[1] = pt2[1] - o[1];
  p20[2] = pt2[2] - o[2];

  double vN = vtkMath::Norm(v);
  double n10 = vtkMath::Norm(p10);
  double n20 = vtkMath::Norm(p20);

  // if there is no motion then return
  if (vN == 0.0)
  {
    return;
  }

  // Project v onto these vector to determine the amount of motion
  // Scale it by the relative size of the motion to the vector length
  double d1 = (vN/n10) * vtkMath::Dot(v,p10) / (vN*n10);
  double d2 = (vN/n20) * vtkMath::Dot(v,p20) / (vN*n20);

  double point1[3], point2[3];
  for (int i=0; i<3; i++)
  {
    point1[i] = o[i] + (1.0+d1)*p10[i];
    point2[i] = o[i] + (1.0+d2)*p20[i];
  }

  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::Rotate(int X, int Y, double *p1, double *p2, double *vpn)
{
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();
  double *center = this->PlaneSource->GetCenter();

  double v[3]; //vector of motion
  double axis[3]; //axis of rotation
  double theta; //rotation angle

  // mouse motion vector in world space
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  // Create axis of rotation and angle of rotation
  vtkMath::Cross(vpn,v,axis);
  if ( vtkMath::Normalize(axis) == 0.0 )
  {
    return;
  }
  int *size = this->CurrentRenderer->GetSize();
  double l2 =
    (X-this->Interactor->GetLastEventPosition()[0])*
    (X-this->Interactor->GetLastEventPosition()[0]) +
    (Y-this->Interactor->GetLastEventPosition()[1])*
    (Y-this->Interactor->GetLastEventPosition()[1]);
  theta = 360.0 * sqrt(l2/(size[0]*size[0]+size[1]*size[1]));

  //Manipulate the transform to reflect the rotation
  this->Transform->Identity();
  this->Transform->Translate(center[0],center[1],center[2]);
  this->Transform->RotateWXYZ(theta,axis);
  this->Transform->Translate(-center[0],-center[1],-center[2]);

  //Set the corners
  double oNew[3], pt1New[3], pt2New[3];
  this->Transform->TransformPoint(o,oNew);
  this->Transform->TransformPoint(pt1,pt1New);
  this->Transform->TransformPoint(pt2,pt2New);

  this->PlaneSource->SetOrigin(oNew);
  this->PlaneSource->SetPoint1(pt1New);
  this->PlaneSource->SetPoint2(pt2New);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::Spin(double *p1, double *p2)
{
  // Mouse motion vector in world space
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  double* normal = this->PlaneSource->GetNormal();
  // Axis of rotation
  double axis[3] = { normal[0], normal[1], normal[2] };
  vtkMath::Normalize(axis);

  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();
  double *center = this->PlaneSource->GetCenter();

  // Radius vector (from center to cursor position)
  double rv[3] = {p2[0] - center[0],
                  p2[1] - center[1],
                  p2[2] - center[2]};

  // Distance between center and cursor location
  double rs = vtkMath::Normalize(rv);

  // Spin direction
  double ax_cross_rv[3];
  vtkMath::Cross(axis,rv,ax_cross_rv);

  // Spin angle
  double theta = vtkMath::DegreesFromRadians( vtkMath::Dot( v, ax_cross_rv ) / rs );

  // Manipulate the transform to reflect the rotation
  this->Transform->Identity();
  this->Transform->Translate(center[0],center[1],center[2]);
  this->Transform->RotateWXYZ(theta,axis);
  this->Transform->Translate(-center[0],-center[1],-center[2]);

  //Set the corners
  double oNew[3], pt1New[3], pt2New[3];
  this->Transform->TransformPoint(o,oNew);
  this->Transform->TransformPoint(pt1,pt1New);
  this->Transform->TransformPoint(pt2,pt2New);

  this->PlaneSource->SetOrigin(oNew);
  this->PlaneSource->SetPoint1(pt1New);
  this->PlaneSource->SetPoint2(pt2New);
  this->PlaneSource->Update();

  this->PositionHandles();
}

// Loop through all points and translate them
void vtkPlaneWidget::Translate(double *p1, double *p2)
{
  //Get the motion vector
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  //int res = this->PlaneSource->GetXResolution();
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  double origin[3], point1[3], point2[3];
  for (int i=0; i<3; i++)
  {
    origin[i] = o[i] + v[i];
    point1[i] = pt1[i] + v[i];
    point2[i] = pt2[i] + v[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::Scale(double *p1, double *p2, int vtkNotUsed(X), int Y)
{
  //Get the motion vector
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  //int res = this->PlaneSource->GetXResolution();
  double *o = this->PlaneSource->GetOrigin();
  double *pt1 = this->PlaneSource->GetPoint1();
  double *pt2 = this->PlaneSource->GetPoint2();

  double center[3];
  center[0] = 0.5 * ( pt1[0] + pt2[0] );
  center[1] = 0.5 * ( pt1[1] + pt2[1] );
  center[2] = 0.5 * ( pt1[2] + pt2[2] );

  // Compute the scale factor
  double sf =
    vtkMath::Norm(v) / sqrt(vtkMath::Distance2BetweenPoints(pt1,pt2));
  if ( Y > this->Interactor->GetLastEventPosition()[1] )
  {
    sf = 1.0 + sf;
  }
  else
  {
    sf = 1.0 - sf;
  }

  // Move the corner points
  double origin[3], point1[3], point2[3];
  for (int i=0; i<3; i++)
  {
    origin[i] = sf * (o[i] - center[i]) + center[i];
    point1[i] = sf * (pt1[i] - center[i]) + center[i];
    point2[i] = sf * (pt2[i] - center[i]) + center[i];
  }

  this->PlaneSource->SetOrigin(origin);
  this->PlaneSource->SetPoint1(point1);
  this->PlaneSource->SetPoint2(point2);
  this->PlaneSource->Update();

  this->PositionHandles();
}

void vtkPlaneWidget::Push(double *p1, double *p2)
{
  //Get the motion vector
  double v[3];
  v[0] = p2[0] - p1[0];
  v[1] = p2[1] - p1[1];
  v[2] = p2[2] - p1[2];

  this->PlaneSource->Push( vtkMath::Dot(v,this->Normal) );
  this->PlaneSource->Update();
  this->PositionHandles();
}

void vtkPlaneWidget::CreateDefaultProperties()
{
  // Handle properties
  this->HandleProperty = vtkProperty::New();
  this->HandleProperty->SetColor(1,1,1);

  this->SelectedHandleProperty = vtkProperty::New();
  this->SelectedHandleProperty->SetColor(1,0,0);

  // Plane properties
  this->PlaneProperty = vtkProperty::New();
  this->PlaneProperty->SetAmbient(1.0);
  this->PlaneProperty->SetAmbientColor(1.0,1.0,1.0);

  this->SelectedPlaneProperty = vtkProperty::New();
  this->SelectRepresentation();
  this->SelectedPlaneProperty->SetAmbient(1.0);
  this->SelectedPlaneProperty->SetAmbientColor(0.0,1.0,0.0);
}

void vtkPlaneWidget::PlaceWidget(double bds[6])
{
  int i;
  double bounds[6], center[3];

  this->AdjustBounds(bds, bounds, center);

  if (this->GetInput() || this->Prop3D)
  {
    if ( this->NormalToYAxis )
    {
      this->PlaneSource->SetOrigin(bounds[0],center[1],bounds[4]);
      this->PlaneSource->SetPoint1(bounds[1],center[1],bounds[4]);
      this->PlaneSource->SetPoint2(bounds[0],center[1],bounds[5]);
    }
    else if ( this->NormalToZAxis )
    {
      this->PlaneSource->SetOrigin(bounds[0],bounds[2],center[2]);
      this->PlaneSource->SetPoint1(bounds[1],bounds[2],center[2]);
      this->PlaneSource->SetPoint2(bounds[0],bounds[3],center[2]);
    }
    else //default or x-normal
    {
      this->PlaneSource->SetOrigin(center[0],bounds[2],bounds[4]);
      this->PlaneSource->SetPoint1(center[0],bounds[3],bounds[4]);
      this->PlaneSource->SetPoint2(center[0],bounds[2],bounds[5]);
    }
  }

  this->PlaneSource->Update();

  // Position the handles at the end of the planes
  this->PositionHandles();

  for (i=0; i<6; i++)
  {
    this->InitialBounds[i] = bounds[i];
  }


  if (this->GetInput() || this->Prop3D)
  {
    this->InitialLength = sqrt((bounds[1]-bounds[0])*(bounds[1]-bounds[0]) +
                               (bounds[3]-bounds[2])*(bounds[3]-bounds[2]) +
                               (bounds[5]-bounds[4])*(bounds[5]-bounds[4]));
  }
  else
  {
    // this means we have to make use of the PolyDataSource, so
    // we just calculate the magnitude of the longest diagonal on
    // the plane and use that as InitialLength
    double origin[3], point1[3], point2[3];
    this->PlaneSource->GetOrigin(origin);
    this->PlaneSource->GetPoint1(point1);
    this->PlaneSource->GetPoint2(point2);
    double sqr1 = 0, sqr2 = 0;
    for (i = 0; i < 3; i++)
    {
      sqr1 += (point1[i] - origin[i]) * (point1[i] - origin[i]);
      sqr2 += (point2[i] - origin[i]) * (point2[i] - origin[i]);
    }

    this->InitialLength = sqrt(sqr1 + sqr2);
  }

  // Set the radius on the sphere handles
  this->SizeHandles();
}

void vtkPlaneWidget::SizeHandles()
{
  double radius = this->vtk3DWidget::SizeHandles(this->HandleSizeFactor);

  if (this->ValidPick && !this->LastPickValid)
  {
    // Adjust factor to preserve old radius.
    double oldradius = this->HandleGeometry[0]->GetRadius();
    if (oldradius != 0 && radius != 0)
    {
      this->HandleSizeFactor = oldradius / radius;
      radius = oldradius;
    }
  }

  this->LastPickValid = this->ValidPick;

  for(int i=0; i<4; i++)
  {
    this->HandleGeometry[i]->SetRadius(radius);
  }

  // Set the height and radius of the cone
  this->ConeSource->SetHeight(2.0*radius);
  this->ConeSource->SetRadius(radius);
  this->ConeSource2->SetHeight(2.0*radius);
  this->ConeSource2->SetRadius(radius);

}


void vtkPlaneWidget::SelectRepresentation()
{
  if ( ! this->CurrentRenderer )
  {
    return;
  }

  if ( this->Representation == VTK_PLANE_OFF )
  {
    this->CurrentRenderer->RemoveActor(this->PlaneActor);
  }
  else if ( this->Representation == VTK_PLANE_OUTLINE )
  {
    this->CurrentRenderer->RemoveActor(this->PlaneActor);
    this->CurrentRenderer->AddActor(this->PlaneActor);
    this->PlaneMapper->SetInputData( this->PlaneOutline );
    this->PlaneActor->GetProperty()->SetRepresentationToWireframe();
  }
  else if ( this->Representation == VTK_PLANE_SURFACE )
  {
    this->CurrentRenderer->RemoveActor(this->PlaneActor);
    this->CurrentRenderer->AddActor(this->PlaneActor);
    this->PlaneMapper->SetInputConnection( this->PlaneSource->GetOutputPort() );
    this->PlaneActor->GetProperty()->SetRepresentationToSurface();
  }
  else //( this->Representation == VTK_PLANE_WIREFRAME )
  {
    this->CurrentRenderer->RemoveActor(this->PlaneActor);
    this->CurrentRenderer->AddActor(this->PlaneActor);
    this->PlaneMapper->SetInputConnection( this->PlaneSource->GetOutputPort() );
    this->PlaneActor->GetProperty()->SetRepresentationToWireframe();
  }
}

// Description:
// Set/Get the resolution (number of subdivisions) of the plane.
void vtkPlaneWidget::SetResolution(int r)
{
  this->PlaneSource->SetXResolution(r);
  this->PlaneSource->SetYResolution(r);
}

int vtkPlaneWidget::GetResolution()
{
  return this->PlaneSource->GetXResolution();
}

// Description:
// Set/Get the origin of the plane.
void vtkPlaneWidget::SetOrigin(double x, double y, double z)
{
  this->PlaneSource->SetOrigin(x,y,z);
  this->PositionHandles();
}

void vtkPlaneWidget::SetOrigin(double x[3])
{
  this->SetOrigin(x[0], x[1], x[2]);
}

double* vtkPlaneWidget::GetOrigin()
{
  return this->PlaneSource->GetOrigin();
}

void vtkPlaneWidget::GetOrigin(double xyz[3])
{
  this->PlaneSource->GetOrigin(xyz);
}

// Description:
// Set/Get the position of the point defining the first axis of the plane.
void vtkPlaneWidget::SetPoint1(double x, double y, double z)
{
  this->PlaneSource->SetPoint1(x,y,z);
  this->PositionHandles();
}

void vtkPlaneWidget::SetPoint1(double x[3])
{
  this->SetPoint1(x[0], x[1], x[2]);
}

double* vtkPlaneWidget::GetPoint1()
{
  return this->PlaneSource->GetPoint1();
}

void vtkPlaneWidget::GetPoint1(double xyz[3])
{
  this->PlaneSource->GetPoint1(xyz);
}

// Description:
// Set/Get the position of the point defining the second axis of the plane.
void vtkPlaneWidget::SetPoint2(double x, double y, double z)
{
  this->PlaneSource->SetPoint2(x,y,z);
  this->PositionHandles();
}

void vtkPlaneWidget::SetPoint2(double x[3])
{
  this->SetPoint2(x[0], x[1], x[2]);
}

double* vtkPlaneWidget::GetPoint2()
{
  return this->PlaneSource->GetPoint2();
}

void vtkPlaneWidget::GetPoint2(double xyz[3])
{
  this->PlaneSource->GetPoint2(xyz);
}

// Description:
// Set the center of the plane.
void vtkPlaneWidget::SetCenter(double x, double y, double z)
{
  this->PlaneSource->SetCenter(x, y, z);
  this->PositionHandles();
}

// Description:
// Set the center of the plane.
void vtkPlaneWidget::SetCenter(double c[3])
{
  this->SetCenter(c[0], c[1], c[2]);
}

// Description:
// Get the center of the plane.
double* vtkPlaneWidget::GetCenter()
{
  return this->PlaneSource->GetCenter();
}

void vtkPlaneWidget::GetCenter(double xyz[3])
{
  this->PlaneSource->GetCenter(xyz);
}

// Description:
// Set the normal to the plane.
void vtkPlaneWidget::SetNormal(double x, double y, double z)
{
  this->PlaneSource->SetNormal(x, y, z);
  this->PositionHandles();
}

// Description:
// Set the normal to the plane.
void vtkPlaneWidget::SetNormal(double n[3])
{
  this->SetNormal(n[0], n[1], n[2]);
}

// Description:
// Get the normal to the plane.
double* vtkPlaneWidget::GetNormal()
{
  return this->PlaneSource->GetNormal();
}

void vtkPlaneWidget::GetNormal(double xyz[3])
{
  this->PlaneSource->GetNormal(xyz);
}

void vtkPlaneWidget::GetPolyData(vtkPolyData *pd)
{
  pd->ShallowCopy(this->PlaneSource->GetOutput());
}

vtkPolyDataAlgorithm *vtkPlaneWidget::GetPolyDataAlgorithm()
{
  return this->PlaneSource;
}

void vtkPlaneWidget::GetPlane(vtkPlane *plane)
{
  if ( plane == NULL )
  {
    return;
  }

  plane->SetNormal(this->GetNormal());
  plane->SetOrigin(this->GetCenter());
}

void vtkPlaneWidget::UpdatePlacement(void)
{
  this->PlaneSource->Update();
  this->PositionHandles();
}