Skip to content

ReadOBJ

vtk-examples/Cxx/IO/ReadOBJ


Description

This example demonstrates how to read a Wavefront OBJ file. The result is displayed.

Other languages

See (Java), (CSharp)

Question

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

Code

ReadOBJ.cxx

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

#include <string>

int main(int argc, char* argv[])
{
  // Parse command line arguments
  if (argc != 2)
  {
    std::cout << "Usage: " << argv[0] << "Filename(.obj) e.g trumpet.obj"
              << std::endl;
    return EXIT_FAILURE;
  }

  std::string filename = argv[1];
  vtkNew<vtkOBJReader> reader;
  reader->SetFileName(filename.c_str());
  reader->Update();

  // Visualize
  vtkNew<vtkNamedColors> colors;
  vtkColor3d backgroundColor = colors->GetColor3d("SpringGreen");
  vtkColor3d actorColor = colors->GetColor3d("HoneyDew");

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

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->GetProperty()->SetDiffuseColor(actorColor.GetData());

  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->SetBackground(backgroundColor.GetData());
  renderer->ResetCamera();
  renderer->GetActiveCamera()->Azimuth(30);
  renderer->GetActiveCamera()->Elevation(30);
  renderer->GetActiveCamera()->Dolly(1.5);
  renderer->ResetCameraClippingRange();

  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("ReadOBJ");

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

  renderWindow->SetSize(640, 480);
  renderWindow->Render();

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ReadOBJ)

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

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

Download and Build ReadOBJ

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

cd ReadOBJ/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:

./ReadOBJ

WINDOWS USERS

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