Tetrahedron

VTKEx/Cxx/GeometricObjects/Tetrahedron

Description

Tetrahedron. The tetrahedron is a primary three-dimensional cell. The tetrahedron is defined by a list of four nonplanar points. The tetrahedron has six edges and four triangular faces.

Other languages

See (Python), (CSharp)

Question

If you have a simple question about this example contact us at VTKExProject If your question is more complex and may require extended discussion, please use the VTK Discourse Forum

Code

Tetrahedron.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkCellArray.h>
#include <vtkCellType.h>
#include <vtkDataSetMapper.h>
#include <vtkNamedColors.h>
#include <vtkPoints.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkTetra.h>
#include <vtkUnstructuredGrid.h>

int main(int, char*[])
{
  vtkSmartPointer<vtkNamedColors> colors =
    vtkSmartPointer<vtkNamedColors>::New();

  vtkSmartPointer< vtkPoints > points =
    vtkSmartPointer< vtkPoints > :: New();
  points->InsertNextPoint(0, 0, 0);
  points->InsertNextPoint(1, 0, 0);
  points->InsertNextPoint(1, 1, 0);
  points->InsertNextPoint(0, 1, 1);
  points->InsertNextPoint(5, 5, 5);
  points->InsertNextPoint(6, 5, 5);
  points->InsertNextPoint(6, 6, 5);
  points->InsertNextPoint(5, 6, 6);

  // Method 1
  vtkSmartPointer<vtkUnstructuredGrid> unstructuredGrid1 =
    vtkSmartPointer<vtkUnstructuredGrid>::New();
  unstructuredGrid1->SetPoints(points);

  vtkIdType ptIds[] = {0, 1, 2, 3};
  unstructuredGrid1->InsertNextCell( VTK_TETRA, 4, ptIds );

  // Method 2
  vtkSmartPointer<vtkUnstructuredGrid> unstructuredGrid2 =
    vtkSmartPointer<vtkUnstructuredGrid>::New();
  unstructuredGrid2->SetPoints(points);

  vtkSmartPointer<vtkTetra> tetra =
    vtkSmartPointer<vtkTetra>::New();

  tetra->GetPointIds()->SetId(0, 4);
  tetra->GetPointIds()->SetId(1, 5);
  tetra->GetPointIds()->SetId(2, 6);
  tetra->GetPointIds()->SetId(3, 7);

  vtkSmartPointer<vtkCellArray> cellArray =
    vtkSmartPointer<vtkCellArray>::New();
  cellArray->InsertNextCell(tetra);
  unstructuredGrid2->SetCells(VTK_TETRA, cellArray);

  // Create a mapper and actor
  vtkSmartPointer<vtkDataSetMapper> mapper1 = 
    vtkSmartPointer<vtkDataSetMapper>::New();
  mapper1->SetInputData(unstructuredGrid1);

  vtkSmartPointer<vtkActor> actor1 = 
    vtkSmartPointer<vtkActor>::New();
  actor1->SetMapper(mapper1);
  actor1->GetProperty()->SetColor(colors->GetColor3d("Cyan").GetData());

  // Create a mapper and actor
  vtkSmartPointer<vtkDataSetMapper> mapper2 = 
    vtkSmartPointer<vtkDataSetMapper>::New();
  mapper2->SetInputData(unstructuredGrid2);

  vtkSmartPointer<vtkActor> actor2 = 
    vtkSmartPointer<vtkActor>::New();
  actor2->SetMapper(mapper2);
  actor2->GetProperty()->SetColor(colors->GetColor3d("Yellow").GetData());

  // Create a renderer, render window, and interactor
  vtkSmartPointer<vtkRenderer> renderer = 
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow = 
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->SetWindowName("Tetrahedron");
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = 
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  // Add the actor to the scene
  renderer->AddActor(actor1);
  renderer->AddActor(actor2);
  renderer->SetBackground(colors->GetColor3d("DarkGreen").GetData());
  renderer->ResetCamera();
  renderer->GetActiveCamera()->Azimuth(-10);
  renderer->GetActiveCamera()->Elevation(-20);

  // Render and interact
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(Tetrahedron)

find_package(VTK COMPONENTS 
  vtkvtkCommonColor
  vtkvtkCommonCore
  vtkvtkCommonDataModel
  vtkvtkInteractionStyle
  vtkvtkRenderingContextOpenGL2
  vtkvtkRenderingCore
  vtkvtkRenderingFreeType
  vtkvtkRenderingGL2PSOpenGL2
  vtkvtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping Tetrahedron: ${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(Tetrahedron MACOSX_BUNDLE Tetrahedron.cxx )
  target_link_libraries(Tetrahedron PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(Tetrahedron MACOSX_BUNDLE Tetrahedron.cxx )
  target_link_libraries(Tetrahedron PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS Tetrahedron
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build Tetrahedron

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

cd Tetrahedron/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:

./Tetrahedron

WINDOWS USERS

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