PolyDataGetPoint

vtk-examples/Cxx/PolyData/PolyDataGetPoint

Description¶

This example demonstrates how to obtain the coordinates of a point in a vtkPolyData object.

Suggested by Sara Rolfe

Other languages

See (CSharp)

Question

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Code¶

PolyDataGetPoint.cxx

#include <vtkNew.h>
#include <vtkPolyData.h>
#include <vtkSphereSource.h>

int main(int, char*[])
{
  // Create a sphere
  vtkNew<vtkSphereSource> sphereSource;
  sphereSource->Update();

  vtkPolyData* polydata = sphereSource->GetOutput();

  // Write all of the coordinates of the points in the vtkPolyData to the
  // console.
  for (vtkIdType i = 0; i < polydata->GetNumberOfPoints(); i++)
  {
    double p[3];
    polydata->GetPoint(i, p);
    // This is identical to:
    // polydata->GetPoints()->GetPoint(i,p);
    std::cout << "Point " << i << " : (" << p[0] << " " << p[1] << " " << p[2]
              << ")" << std::endl;
  }

  return EXIT_SUCCESS;
}

CMakeLists.txt¶

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(PolyDataGetPoint)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersSources
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping PolyDataGetPoint: ${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(PolyDataGetPoint MACOSX_BUNDLE PolyDataGetPoint.cxx )
  target_link_libraries(PolyDataGetPoint PRIVATE ${VTK_LIBRARIES})
else()
  # 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(PolyDataGetPoint MACOSX_BUNDLE PolyDataGetPoint.cxx )
  target_link_libraries(PolyDataGetPoint PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS PolyDataGetPoint
    MODULES ${VTK_LIBRARIES}
    )
endif()

Download and Build PolyDataGetPoint¶

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

cd PolyDataGetPoint/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:

./PolyDataGetPoint

WINDOWS USERS

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