VTK/Examples/Cxx/PolyData/WarpScalar

WarpScalar.cxx

#include <vtkActor.h>
#include <vtkDoubleArray.h>
#include <vtkPointData.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkWarpScalar.h>

int main(int, char *[])
{
  // Create a sphere
  vtkSmartPointer<vtkSphereSource> sphereSource = 
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->Update();
  
  // Create Scalars
  vtkSmartPointer<vtkDoubleArray> scalars =
    vtkSmartPointer<vtkDoubleArray>::New();
  int numberOfPoints = sphereSource->GetOutput()->GetNumberOfPoints();
  scalars->SetNumberOfTuples(numberOfPoints);

  for(vtkIdType i = 0; i < numberOfPoints; ++i)
    {
    scalars->SetTuple1(i, drand48()/7.);
    }

  sphereSource->GetOutput()->GetPointData()->SetScalars(scalars);

  vtkSmartPointer<vtkWarpScalar> warpScalar = 
    vtkSmartPointer<vtkWarpScalar>::New();
  warpScalar->SetInputConnection(sphereSource->GetOutputPort());
  warpScalar->SetScaleFactor(1); // use the scalars themselves

  // Required for SetNormal to have an effect
  warpScalar->UseNormalOn();
  warpScalar->SetNormal(0, 0, 1);

  warpScalar->Update();
  
  // Create a mapper and actor
  vtkSmartPointer<vtkPolyDataMapper> mapper = 
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(warpScalar->GetOutputPort());
 
  vtkSmartPointer<vtkActor> actor = 
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);
 
  // Visualize
  vtkSmartPointer<vtkRenderer> renderer = 
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow = 
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = 
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);
 
  renderer->AddActor(actor);
  renderer->SetBackground(1,1,1); // Background color white
 
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

Please try the new VTKExamples website.

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(WarpScalar)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(WarpScalar MACOSX_BUNDLE WarpScalar.cxx)

if(VTK_LIBRARIES)
  target_link_libraries(WarpScalar ${VTK_LIBRARIES})
else()
  target_link_libraries(WarpScalar vtkHybrid vtkWidgets)
endif()

Download and Build WarpScalar

Click here to download WarpScalar. and its CMakeLists.txt file.

Once the tarball WarpScalar.tar has been downloaded and extracted,

cd WarpScalar/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:

./WarpScalar

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