Skip to content

PolygonalSurfacePointPlacer

vtk-examples/Cxx/PolyData/PolygonalSurfacePointPlacer


Description

This example demonstrates how to draw curves on a surface.

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

PolygonalSurfacePointPlacer.cxx

#include <vtkActor.h>
#include <vtkCallbackCommand.h>
#include <vtkContourWidget.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkOrientedGlyphContourRepresentation.h>
#include <vtkPolyDataCollection.h>
#include <vtkPolyDataMapper.h>
#include <vtkPolygonalSurfacePointPlacer.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>

#include <iostream>
#include <string>

namespace {

class MyCallback : public vtkCallbackCommand
{
public:
  static MyCallback* New()
  {
    return new MyCallback;
  }
  MyCallback()
  {
  }

  virtual void Execute(vtkObject* caller, unsigned long, void*)
  {
    vtkContourWidget* contourWidget =
        reinterpret_cast<vtkContourWidget*>(caller);
    vtkContourRepresentation* rep = static_cast<vtkContourRepresentation*>(
        contourWidget->GetRepresentation());
    std::cout << "There are " << rep->GetNumberOfNodes() << " nodes."
              << std::endl;
  }

  void SetSphereSource(vtkSmartPointer<vtkSphereSource> sphere)
  {
    this->SphereSource = sphere;
  }

private:
  vtkSmartPointer<vtkSphereSource> SphereSource;
};

} // namespace

int main(int, char*[])
{
  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkSphereSource> sphereSource;
  sphereSource->SetRadius(5);
  sphereSource->Update();

  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputConnection(sphereSource->GetOutputPort());

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

  // Create the RenderWindow, Renderer.
  vtkNew<vtkRenderer> renderer;
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("PolygonalSurfacePointPlacer");

  vtkNew<vtkRenderWindowInteractor> interactor;
  interactor->SetRenderWindow(renderWindow);

  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("CadetBlue").GetData());

  vtkNew<vtkContourWidget> contourWidget;
  contourWidget->SetInteractor(interactor);

  vtkNew<MyCallback> callback;
  callback->SetSphereSource(sphereSource);
  contourWidget->AddObserver(vtkCommand::InteractionEvent, callback);

  vtkOrientedGlyphContourRepresentation* rep =
      dynamic_cast<vtkOrientedGlyphContourRepresentation*>(
          contourWidget->GetRepresentation());

  vtkNew<vtkPolygonalSurfacePointPlacer> pointPlacer;
  pointPlacer->AddProp(actor);
  pointPlacer->GetPolys()->AddItem(sphereSource->GetOutput());

  rep->GetLinesProperty()->SetColor(colors->GetColor3d("Crimson").GetData());
  rep->GetLinesProperty()->SetLineWidth(3.0);
  rep->SetPointPlacer(pointPlacer);

  contourWidget->EnabledOn();
  renderer->ResetCamera();
  renderWindow->Render();
  interactor->Initialize();

  interactor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(PolygonalSurfacePointPlacer)

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

if (NOT VTK_FOUND)
  message(FATAL_ERROR "PolygonalSurfacePointPlacer: 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(PolygonalSurfacePointPlacer MACOSX_BUNDLE PolygonalSurfacePointPlacer.cxx )
  target_link_libraries(PolygonalSurfacePointPlacer PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS PolygonalSurfacePointPlacer
  MODULES ${VTK_LIBRARIES}
)

Download and Build PolygonalSurfacePointPlacer

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

cd PolygonalSurfacePointPlacer/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:

./PolygonalSurfacePointPlacer

WINDOWS USERS

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