CylinderExample

VTKExamples/Cxx/GeometricObjects/CylinderExample


Description

This example creates a minimal visualization program, demonstrating VTK's basic rendering and pipeline creation.

Note

This original C++ source code for this example is here.

Other Languages

See (Python), (Java)

Code

CylinderExample.cxx

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

#include <array>

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

  // Set the background color.
  std::array<unsigned char, 4> bkg{{26, 51, 102, 255}};
  colors->SetColor("BkgColor", bkg.data());

  // This creates a polygonal cylinder model with eight circumferential facets
  // (i.e, in practice an octagonal prism).
  vtkSmartPointer<vtkCylinderSource> cylinder =
      vtkSmartPointer<vtkCylinderSource>::New();
  cylinder->SetResolution(8);

  // The mapper is responsible for pushing the geometry into the graphics
  // library. It may also do color mapping, if scalars or other attributes are
  // defined.
  vtkSmartPointer<vtkPolyDataMapper> cylinderMapper =
      vtkSmartPointer<vtkPolyDataMapper>::New();
  cylinderMapper->SetInputConnection(cylinder->GetOutputPort());

  // The actor is a grouping mechanism: besides the geometry (mapper), it
  // also has a property, transformation matrix, and/or texture map.
  // Here we set its color and rotate it around the X and Y axes.
  vtkSmartPointer<vtkActor> cylinderActor = vtkSmartPointer<vtkActor>::New();
  cylinderActor->SetMapper(cylinderMapper);
  cylinderActor->GetProperty()->SetColor(
      colors->GetColor4d("Tomato").GetData());
  cylinderActor->RotateX(30.0);
  cylinderActor->RotateY(-45.0);

  // The renderer generates the image
  // which is then displayed on the render window.
  // It can be thought of as a scene to which the actor is added
  vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
  renderer->AddActor(cylinderActor);
  renderer->SetBackground(colors->GetColor3d("BkgColor").GetData());
  // Zoom in a little by accessing the camera and invoking its "Zoom" method.
  renderer->ResetCamera();
  renderer->GetActiveCamera()->Zoom(1.5);

  // The render window is the actual GUI window
  // that appears on the computer screen
  vtkSmartPointer<vtkRenderWindow> renderWindow =
      vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->SetSize(300, 300);
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("Cylinder");

  // The render window interactor captures mouse events
  // and will perform appropriate camera or actor manipulation
  // depending on the nature of the events.
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
      vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  // This starts the event loop and as a side effect causes an initial render.
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(CylinderExample)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkFiltersSources
  vtkInteractionStyle
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping CylinderExample: ${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(CylinderExample MACOSX_BUNDLE CylinderExample.cxx )
  target_link_libraries(CylinderExample PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(CylinderExample MACOSX_BUNDLE CylinderExample.cxx )
  target_link_libraries(CylinderExample PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS CylinderExample
    MODULES ${VTK_LIBRARIES}
    )
endif () 

Download and Build CylinderExample

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

cd CylinderExample/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:

./CylinderExample

WINDOWS USERS

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