ReadAllPolyDataTypes

VTKExamples/Cxx/IO/ReadAllPolyDataTypes


Description

This example selects the vtkPolyData reader by inspecting the extension of the file. The example processes every file passed as an argument. This assumes all of the files are modeled in the same coordinate system.

Info

The procedure ReadPolyData is a reusable procedure. Copy and paste it into other examples that can benefit from reading any vtkPolyData.

Code

ReadAllPolyDataTypes.cxx

#include <vtkSmartPointer.h>

#include <vtkBYUReader.h>
#include <vtkOBJReader.h>
#include <vtkPLYReader.h>
#include <vtkPolyDataReader.h>
#include <vtkSTLReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkSphereSource.h>

#include <vtkActor.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkCamera.h>

#include <vtkNamedColors.h>
#include <vtkTimerLog.h>
#include <vtksys/SystemTools.hxx>

#include <string>
#include <algorithm>
#include <random>
#include <array>

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

int main (int argc, char *argv[])
{
  // Vis Pipeline
  auto colors = vtkSmartPointer<vtkNamedColors>::New();

  auto renderer = vtkSmartPointer<vtkRenderer>::New();

  auto renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->SetSize(640, 480);
  renderWindow->AddRenderer(renderer);

  auto interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
  interactor->SetRenderWindow(renderWindow);

  renderer->SetBackground(colors->GetColor3d("Wheat").GetData());
  renderer->UseHiddenLineRemovalOn();

  std::mt19937 mt(4355412); //Standard mersenne_twister_engine
  std::uniform_real_distribution<double> distribution(.6, 1.0);

  // PolyData file pipeline
  for (int i = 1; i < argc; ++i)
  {
    std::cout << "Loading: " << argv[i] << std::endl;
    auto polyData = ReadPolyData(argv[i]);

    // Visualize
    auto mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputData(polyData);

    std::array<double, 3> randomColor;
    randomColor[0] = distribution(mt);
    randomColor[1] = distribution(mt);
    randomColor[2] = distribution(mt);
    auto backProp = vtkSmartPointer<vtkProperty>::New();
    backProp->SetDiffuseColor(colors->GetColor3d("Banana").GetData());
    backProp->SetSpecular(.6);
    backProp->SetSpecularPower(30);

    auto actor = vtkSmartPointer<vtkActor>::New();
    actor->SetMapper(mapper);
    actor->SetBackfaceProperty(backProp);
    actor->GetProperty()->SetDiffuseColor(randomColor.data());
    actor->GetProperty()->SetSpecular(.3);
    actor->GetProperty()->SetSpecularPower(30);
    renderer->AddActor(actor);
  }

  renderWindow->Render();
  interactor->Start();

  return EXIT_SUCCESS;
}

namespace
{
vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName)
{
  vtkSmartPointer<vtkPolyData> polyData;
  std::string extension =
    vtksys::SystemTools::GetFilenameLastExtension(std::string(fileName));

  // Drop the case of the extension
  std::transform(extension.begin(), extension.end(),
                 extension.begin(), ::tolower);

  if (extension == ".ply")
  {
    auto reader = vtkSmartPointer<vtkPLYReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".vtp")
  {
    auto reader = vtkSmartPointer<vtkXMLPolyDataReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".obj")
  {
    auto reader = vtkSmartPointer<vtkOBJReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".stl")
  {
    auto reader = vtkSmartPointer<vtkSTLReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".vtk")
  {
    auto reader = vtkSmartPointer<vtkPolyDataReader>::New();
    reader->SetFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else if (extension == ".g")
  {
    auto reader = vtkSmartPointer<vtkBYUReader>::New();
    reader->SetGeometryFileName (fileName);
    reader->Update();
    polyData = reader->GetOutput();
  }
  else
  {
    auto source = vtkSmartPointer<vtkSphereSource>::New();
    source->Update();
    polyData = source->GetOutput();
  }
  return polyData;
}
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ReadAllPolyDataTypes)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkCommonSystem
  vtkFiltersSources
  vtkIOGeometry
  vtkIOLegacy
  vtkIOPLY
  vtkIOXML
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping ReadAllPolyDataTypes: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(ReadAllPolyDataTypes MACOSX_BUNDLE ReadAllPolyDataTypes.cxx )
  target_link_libraries(ReadAllPolyDataTypes PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(ReadAllPolyDataTypes MACOSX_BUNDLE ReadAllPolyDataTypes.cxx )
  target_link_libraries(ReadAllPolyDataTypes PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS ReadAllPolyDataTypes
    MODULES ${VTK_LIBRARIES}
    )
endif () 

Download and Build ReadAllPolyDataTypes

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

cd ReadAllPolyDataTypes/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:

./ReadAllPolyDataTypes

WINDOWS USERS

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