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SimplePointsReader

vtk-examples/Cxx/IO/SimplePointsReader


Description

A file of XYZ coordinates is a very easy format that can be used for simple storage from many applications. This example demonstrates how to read this type of file into a polydata object. An example file of three points would look like this:

 0.0 0.0 0.0
 1.0 0.0 0.0
 0.0 1.0 0.0

As a demo, save the above three lines to a file called simple.xyz and call the executable resulting from the code below with

 ./SimplePointsReader simple.xyz

from the build directory.

Seealso

For the reverse operation, writing a points file, see the SimplePointsWriter example.

Other languages

See (Java), (CSharp)

Question

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

Code

SimplePointsReader.cxx

#include <vtkActor.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSimplePointsReader.h>

int main(int argc, char* argv[])
{
  vtkNew<vtkNamedColors> colors;

  // Verify input arguments
  if (argc != 2)
  {
    std::cout << "Usage: " << argv[0] << " Filename(.xyz) e.g coords.txt"
              << std::endl;
    return EXIT_FAILURE;
  }

  // Read the file
  vtkNew<vtkSimplePointsReader> reader;
  reader->SetFileName(argv[1]);
  reader->Update();

  // Visualize
  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputConnection(reader->GetOutputPort());

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->GetProperty()->SetPointSize(6);
  actor->GetProperty()->SetColor(colors->GetColor3d("Gold").GetData());

  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("DarkGreen").GetData());

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

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

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

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(SimplePointsReader)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkIOLegacy
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  QUIET
)

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

Download and Build SimplePointsReader

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

cd SimplePointsReader/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:

./SimplePointsReader

WINDOWS USERS

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