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OBJImporter

vtk-examples/Cxx/IO/OBJImporter


Question

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Code

OBJImporter.cxx

#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkOBJImporter.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkTexture.h>

int main(int argc, char* argv[])
{
  if (argc < 4)
  {
    std::cout
        << "Usage: " << argv[0]
        << " objfile mtlfile texturepath e.g. doorman.obj doorman.mtl doorman"
        << std::endl;
    return EXIT_FAILURE;
  }
  vtkNew<vtkOBJImporter> importer;
  importer->SetFileName(argv[1]);
  importer->SetFileNameMTL(argv[2]);
  importer->SetTexturePath(argv[3]);

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkRenderer> renderer;
  vtkNew<vtkRenderWindow> renWin;
  vtkNew<vtkRenderWindowInteractor> iren;

  renderer->SetBackground2(colors->GetColor3d("Silver").GetData());
  renderer->SetBackground(colors->GetColor3d("Gold").GetData());
  renderer->GradientBackgroundOn();
  renWin->AddRenderer(renderer);
  renderer->UseHiddenLineRemovalOn();
  renWin->AddRenderer(renderer);
  renWin->SetSize(640, 480);
  renWin->SetWindowName("OBJImporter");

  iren->SetRenderWindow(renWin);
  importer->SetRenderWindow(renWin);
  importer->Update();

  auto actors = renderer->GetActors();
  actors->InitTraversal();
  std::cout << "There are " << actors->GetNumberOfItems() << " actors"
            << std::endl;

  for (vtkIdType a = 0; a < actors->GetNumberOfItems(); ++a)
  {
    std::cout << importer->GetOutputDescription(a) << std::endl;

    vtkActor* actor = actors->GetNextActor();

    // OBJImporter turns texture interpolation off
    if (actor->GetTexture())
    {
      std::cout << "Has texture\n";
      actor->GetTexture()->InterpolateOn();
    }

    vtkPolyData* pd =
        dynamic_cast<vtkPolyData*>(actor->GetMapper()->GetInput());

    vtkPolyDataMapper* mapper =
        dynamic_cast<vtkPolyDataMapper*>(actor->GetMapper());
    mapper->SetInputData(pd);
  }
  renWin->Render();
  iren->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(OBJImporter)

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

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

Download and Build OBJImporter

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

cd OBJImporter/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:

./OBJImporter

WINDOWS USERS

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