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Arbitrary3DCursor

vtk-examples/Cxx/Visualization/Arbitrary3DCursor


Question

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Code

Arbitrary3DCursor.cxx

#include <vtkActor.h>
#include <vtkCallbackCommand.h>
#include <vtkCommand.h>
#include <vtkConeSource.h>
#include <vtkGlyph3D.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPointWidget.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProbeFilter.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkTextActor.h>
#include <vtkTextProperty.h>
#include <vtkXMLPolyDataReader.h>

#include <iostream>
#include <sstream>
#include <string>

// This does the actual work: updates the probe.
// Callback for the interaction.
class vtkmyPWCallback : public vtkCallbackCommand
{
public:
  vtkmyPWCallback() = default;

  static vtkmyPWCallback* New()
  {
    return new vtkmyPWCallback;
  }
  virtual void Execute(vtkObject* caller, unsigned long, void*)
  {
    vtkPointWidget* pointWidget = reinterpret_cast<vtkPointWidget*>(caller);
    pointWidget->GetPolyData(this->PolyData);
    double position[3];
    pointWidget->GetPosition(position);
    std::ostringstream text;
    text << "cursor: " << std::fixed << std::setprecision(4) << position[0]
         << ", " << position[1] << ", " << position[2];
    this->PositionActor->SetInput(text.str().c_str());
    this->CursorActor->VisibilityOn();
  }

  vtkPolyData* PolyData = nullptr;
  vtkActor* CursorActor = nullptr;
  vtkTextActor* PositionActor = nullptr;
};

int main(int argc, char* argv[])
{
  vtkSmartPointer<vtkPolyData> inputPolyData;

  if (argc > 1)
  {
    vtkNew<vtkXMLPolyDataReader> reader;
    reader->SetFileName(argv[1]);
    reader->Update();
    inputPolyData = reader->GetOutput();
  }
  else
  {
    vtkNew<vtkSphereSource> sphereSource;
    sphereSource->SetPhiResolution(15);
    sphereSource->SetThetaResolution(15);
    sphereSource->Update();
    inputPolyData = sphereSource->GetOutput();
  }

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkPolyData> point;

  vtkNew<vtkProbeFilter> probe;
  probe->SetInputData(point);
  probe->SetSourceData(inputPolyData);

  // Create glyph.
  vtkNew<vtkConeSource> cone;
  cone->SetResolution(16);

  vtkNew<vtkGlyph3D> glyph;
  glyph->SetInputConnection(probe->GetOutputPort());
  glyph->SetSourceConnection(cone->GetOutputPort());
  glyph->SetVectorModeToUseVector();
  glyph->SetScaleModeToDataScalingOff();
  glyph->SetScaleFactor(inputPolyData->GetLength() * 0.1);

  vtkNew<vtkPolyDataMapper> glyphMapper;
  glyphMapper->SetInputConnection(glyph->GetOutputPort());

  vtkNew<vtkActor> glyphActor;
  glyphActor->SetMapper(glyphMapper);
  glyphActor->VisibilityOn();

  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputData(inputPolyData);

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->GetProperty()->SetRepresentationToWireframe();
  actor->GetProperty()->SetColor(colors->GetColor3d("gold").GetData());

  vtkNew<vtkTextActor> textActor;
  textActor->GetTextProperty()->SetFontSize(12);
  textActor->SetPosition(10, 20);
  textActor->SetInput("cursor:");
  textActor->GetTextProperty()->SetColor(colors->GetColor3d("White").GetData());

  // Create the RenderWindow, Render1er and both Actors.
  vtkNew<vtkRenderer> ren1;
  vtkNew<vtkRenderWindow> renWin;
  renWin->AddRenderer(ren1);

  vtkNew<vtkRenderWindowInteractor> iren;
  iren->SetRenderWindow(renWin);

  // The SetInteractor method is how 3D widgets are associated with the render
  // window interactor. Internally, SetInteractor sets up a bunch of callbacks
  // using the Command/Observer mechanism (AddObserver()).
  vtkNew<vtkmyPWCallback> myCallback;
  myCallback->PolyData = point;
  myCallback->CursorActor = glyphActor;
  myCallback->PositionActor = textActor;

  // The point widget is used probe the dataset.
  vtkNew<vtkPointWidget> pointWidget;
  pointWidget->SetInteractor(iren);
  pointWidget->SetInputData(inputPolyData);
  pointWidget->AllOff();
  pointWidget->PlaceWidget();
  pointWidget->AddObserver(vtkCommand::InteractionEvent, myCallback);

  ren1->AddActor(glyphActor);
  ren1->AddActor(actor);
  ren1->AddActor2D(textActor);

  // Add the actors to the renderer, set the background and size.
  ren1->GradientBackgroundOn();
  ren1->SetBackground(colors->GetColor3d("SlateGray").GetData());
  ren1->SetBackground2(colors->GetColor3d("Wheat").GetData());

  renWin->SetSize(300, 300);
  renWin->SetWindowName("Arbitrary3DCursor");
  renWin->Render();
  pointWidget->On();

  // Render the image
  iren->Initialize();
  renWin->Render();

  iren->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(Arbitrary3DCursor)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  CommonDataModel
  FiltersCore
  FiltersSources
  IOXML
  InteractionStyle
  InteractionWidgets
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "Arbitrary3DCursor: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(Arbitrary3DCursor MACOSX_BUNDLE Arbitrary3DCursor.cxx )
  target_link_libraries(Arbitrary3DCursor PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS Arbitrary3DCursor
  MODULES ${VTK_LIBRARIES}
)

Download and Build Arbitrary3DCursor

Click here to download Arbitrary3DCursor and its CMakeLists.txt file. Once the tarball Arbitrary3DCursor.tar has been downloaded and extracted,

cd Arbitrary3DCursor/build

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./Arbitrary3DCursor

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.