ProjectedTexture

Description¶

vtkProjectedTexture is tricky to set up. Picking the right parameters will take some iterations. The example uses vtkFrustumSource to help understand the parameters.

Cite

This example was inspired by Thomas Kilgus, German Cancer Research Center (DKFZ), Div. Medical and Biological Informatics, Junior group: Computer-assisted Interventions (E131), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany

Question

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

Code¶

ProjectedTexture.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkFrustumSource.h>
#include <vtkImageData.h>
#include <vtkImageReader2.h>
#include <vtkImageReader2Factory.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPlanes.h>
#include <vtkPointData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProjectedTexture.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkTexture.h>

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

#include <vtksys/SystemTools.hxx>

#include <iostream>
#include <string>

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

int main(int argc, char* argv[])
{
  if (argc < 3)
  {
    std::cout << "Usage: " << argv[0]
              << " polydata texture e.g. fran_cut.vtk fran_cut.png"
              << std::endl;
    return EXIT_FAILURE;
  }
  vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argv[1]);

  vtkNew<vtkImageReader2Factory> readerFactory;
  vtkSmartPointer<vtkImageReader2> textureFile;
  textureFile.TakeReference(readerFactory->CreateImageReader2(argv[2]));
  textureFile->SetFileName(argv[2]);
  textureFile->Update();

  vtkNew<vtkNamedColors> colors;

  double center[3];
  polyData->GetCenter(center);
  std::cout << "Center: " << center[0] << ", " << center[1] << ", " << center[2]
            << std::endl;
  vtkNew<vtkCamera> camera;
  camera->SetPosition(center[0], center[1] + .0375, center[2] + .5);
  camera->SetFocalPoint(center[0], center[1] + .0375, center[2]);
  camera->Azimuth(-45);
  camera->Roll(-90);
  camera->SetClippingRange(.5, .6);
  double planesArray[24];

  camera->GetFrustumPlanes(1.0, planesArray);

  // Settings for vtkProjectedTexture

  double aspect[3];
  aspect[1] = 1.0;
  aspect[2] = 1.0;
  aspect[0] = 1.0;
  //(1.0/ (vtkMath::RadiansFromDegrees(std::tan(camera->GetViewAngle()))))
  /// 2.0;
  std::cout << "Aspect: " << aspect[0] << ", " << aspect[1] << ", " << aspect[2]
            << std::endl;

  vtkNew<vtkProjectedTexture> projectedTexture;

  projectedTexture->SetAspectRatio(aspect);
  projectedTexture->SetPosition(camera->GetPosition());
  projectedTexture->SetFocalPoint(camera->GetFocalPoint());
  projectedTexture->SetUp(camera->GetViewUp()[0], camera->GetViewUp()[1],
                          camera->GetViewUp()[2]);

  projectedTexture->SetInputData(
      polyData); // This can be the same as the one to project on.
  projectedTexture->Update();

  // Map Texture on Surface
  polyData->GetPointData()->SetTCoords(
      projectedTexture->GetOutput()->GetPointData()->GetTCoords());

  vtkNew<vtkTexture> texture;
  texture->SetInputData(textureFile->GetOutput());

  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputData(polyData);

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->SetTexture(texture);

  vtkNew<vtkPlanes> planes;
  planes->SetFrustumPlanes(planesArray);

  vtkNew<vtkFrustumSource> frustumSource;
  frustumSource->ShowLinesOff();
  frustumSource->SetPlanes(planes);
  frustumSource->Update();

  vtkNew<vtkPolyDataMapper> frustumMapper;
  frustumMapper->SetInputConnection(frustumSource->GetOutputPort());

  vtkNew<vtkActor> frustumActor;
  frustumActor->SetMapper(frustumMapper);
  frustumActor->GetProperty()->EdgeVisibilityOn();
  frustumActor->GetProperty()->SetColor(colors->GetColor3d("Banana").GetData());
  frustumActor->GetProperty()->SetOpacity(.5);
  frustumActor->GetProperty()->SetRepresentationToWireframe();

  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->AddActor(frustumActor);
  renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());
  renderer->SetActiveCamera(camera);
  camera->Azimuth(180);
  camera->Roll(-90);
  renderer->ResetCameraClippingRange();

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

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

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

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

CMakeLists.txt¶

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ProjectedTexture)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  CommonDataModel
  FiltersModeling
  FiltersSources
  IOGeometry
  IOImage
  IOLegacy
  IOPLY
  IOXML
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

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

Download and Build ProjectedTexture¶

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

cd ProjectedTexture/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:

./ProjectedTexture

WINDOWS USERS

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