VTK/Examples/Cxx/Points/PointOccupancy

NOTE: The classes used in this example require vtk 7.1 or later.

PointOccupancy.cxx

#include <vtkSmartPointer.h>
#include <vtkPointSource.h>
#include <vtkPLYReader.h>
#include <vtkSTLReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkOBJReader.h>

#include <vtkPointOccupancyFilter.h>
#include <vtkThreshold.h>
#include <vtkDataSetMapper.h>
#include <vtkImageData.h>

#include <vtkNamedColors.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkCamera.h>

#include <vtksys/SystemTools.hxx>

static vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName);

int main (int argc, char *argv[])
{
  vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argc > 1 ? argv[1] : "");;
  int dimension = 128;
  vtkSmartPointer<vtkPointOccupancyFilter> occupancy = 
    vtkSmartPointer<vtkPointOccupancyFilter>::New();
  occupancy->SetInputData(polyData);
  occupancy->SetSampleDimensions(dimension, dimension, dimension);
  occupancy->SetOccupiedValue(255);
  occupancy->Update();

  vtkSmartPointer<vtkThreshold> threshold =
    vtkSmartPointer<vtkThreshold>::New();
  threshold->SetInputConnection(occupancy->GetOutputPort());
  threshold->ThresholdByUpper(255);
  threshold->AllScalarsOff();

  vtkSmartPointer<vtkDataSetMapper> mapper =
    vtkSmartPointer<vtkDataSetMapper>::New();
  mapper->SetInputConnection(threshold->GetOutputPort());
  mapper->ScalarVisibilityOff();

  vtkSmartPointer<vtkActor> actor =
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);

  // Colors
  vtkSmartPointer<vtkNamedColors> nc =
    vtkSmartPointer<vtkNamedColors>::New();
  double flesh[3];
  nc->GetColorRGB("moccasin", flesh);
  actor->GetProperty()->SetColor(flesh);

  // Create graphics stuff
  //
  vtkSmartPointer<vtkRenderer> ren1 =
    vtkSmartPointer<vtkRenderer>::New();
  ren1->SetBackground(.3, .4, .6);

  vtkSmartPointer<vtkRenderWindow> renWin =
    vtkSmartPointer<vtkRenderWindow>::New();
  renWin->AddRenderer(ren1);
  renWin->SetSize(512,512);

  vtkSmartPointer<vtkRenderWindowInteractor> iren =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  iren->SetRenderWindow(renWin);
  
  // Add the actors to the renderer, set the background and size
  //
  ren1->AddActor(actor);

  // Generate an interesting view
  //
  ren1->ResetCamera();
  ren1->GetActiveCamera()->Azimuth(120);
  ren1->GetActiveCamera()->Elevation(30);
  ren1->GetActiveCamera()->Dolly(1.25);
  ren1->ResetCameraClippingRange();

  iren->Initialize();
  iren->Start();

  return EXIT_SUCCESS;
}

static vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName)
{
  vtkSmartPointer<vtkPolyData> polyData;
  std::string extension = vtksys::SystemTools::GetFilenameExtension(std::string(fileName));
  if (extension == ".ply")
  {
    vtkSmartPointer<vtkPLYReader> reader =
      vtkSmartPointer<vtkPLYReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".vtp")
  {
    vtkSmartPointer<vtkXMLPolyDataReader> reader =
      vtkSmartPointer<vtkXMLPolyDataReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".obj")
  {
    vtkSmartPointer<vtkOBJReader> reader =
      vtkSmartPointer<vtkOBJReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".stl")
  {
    vtkSmartPointer<vtkSTLReader> reader =
      vtkSmartPointer<vtkSTLReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else
  {
    vtkSmartPointer<vtkPointSource> points =
      vtkSmartPointer<vtkPointSource>::New();
    points->SetNumberOfPoints(1000);
    points->SetRadius(10.0);
    points->SetCenter(vtkMath::Random(-100, 100),
                      vtkMath::Random(-100, 100),
                      vtkMath::Random(-100, 100));
    points->SetDistributionToShell();
    points->Update();
    polyData = points->GetOutput();
  }
  return polyData;
}

Please try the new VTKExamples website.

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(PointOccupancy)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(PointOccupancy MACOSX_BUNDLE PointOccupancy.cxx)

if(VTK_LIBRARIES)
  target_link_libraries(PointOccupancy ${VTK_LIBRARIES})
else()
  target_link_libraries(PointOccupancy vtkHybrid vtkWidgets)
endif()

Download and Build PointOccupancy

Click here to download PointOccupancy. and its CMakeLists.txt file.

Once the tarball PointOccupancy.tar has been downloaded and extracted,

cd PointOccupancy/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:

./PointOccupancy

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