MassProperties

VTKExamples/Cxx/Utilities/MassProperties

Description

This example uses vtkMassProperties to compute the volume of a closed mesh. vtkmassProperties requires triangle with consistent ordering.

Code

MassProperties.cxx

#include <vtkSmartPointer.h>
#include <vtkMassProperties.h>
#include <vtkTriangleFilter.h>
#include <vtkFillHolesFilter.h>
#include <vtkCleanPolyData.h>
#include <vtkPolyDataNormals.h>

#include <vtkBYUReader.h>
#include <vtkOBJReader.h>
#include <vtkPLYReader.h>
#include <vtkPolyDataReader.h>
#include <vtkSTLReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkSphereSource.h>
#include <vtksys/SystemTools.hxx>

namespace
{
vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName);
}

int main (int argc, char *argv[])
{
  vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argc > 1 ? argv[1] : "");;

  vtkSmartPointer<vtkCleanPolyData> cleanPolyDataFilter =
    vtkSmartPointer<vtkCleanPolyData>::New();
  cleanPolyDataFilter->SetInputData(polyData);

  vtkSmartPointer<vtkFillHolesFilter> fillHolesFilter =
    vtkSmartPointer<vtkFillHolesFilter>::New();
  fillHolesFilter->SetInputConnection(cleanPolyDataFilter->GetOutputPort());
  fillHolesFilter->SetHoleSize(1000.0);

  vtkSmartPointer<vtkTriangleFilter> triangleFilter =
    vtkSmartPointer<vtkTriangleFilter>::New();
  triangleFilter->SetInputConnection(fillHolesFilter->GetOutputPort());

  // Make the triangle windong order consistent
  vtkSmartPointer<vtkPolyDataNormals> normals =
    vtkSmartPointer<vtkPolyDataNormals>::New();
  normals->SetInputConnection(triangleFilter->GetOutputPort());
  normals->ConsistencyOn();
  normals->SplittingOff();

  vtkSmartPointer<vtkMassProperties> massProperties =
    vtkSmartPointer<vtkMassProperties>::New();
  massProperties->SetInputConnection(normals->GetOutputPort());
  massProperties->Update();
  massProperties->Print(std::cout);

  return EXIT_SUCCESS;
}

namespace
{
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 if (extension == ".vtk")
  {
    vtkSmartPointer<vtkPolyDataReader> reader =
      vtkSmartPointer<vtkPolyDataReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".g")
  {
    vtkSmartPointer<vtkBYUReader> reader =
      vtkSmartPointer<vtkBYUReader>::New();
    reader->SetGeometryFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else
  {
    vtkSmartPointer<vtkSphereSource> source =
      vtkSmartPointer<vtkSphereSource>::New();
    source->SetPhiResolution(51);
    source->SetThetaResolution(51);
    source->Update();
    polyData = source->GetOutput();
  }
  return polyData;
}
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(MassProperties)

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

add_executable(MassProperties MACOSX_BUNDLE MassProperties.cxx )

target_link_libraries(MassProperties ${VTK_LIBRARIES})

Download and Build MassProperties

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

cd MassProperties/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:

./MassProperties

WINDOWS USERS

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