ITK/Examples/Meshes/ReadWrite

itk::Mesh objects may be written and read to and from a variety of file formats. In this example, a spherical mesh is created, written to file, and read back in in a format specified by the user.

Contributed by: Davis Vigneault

ReadWrite.cxx

<source lang="cpp"> // Include the relevant header files

1. include "itkMesh.h"
2. include "itkRegularSphereMeshSource.h"
3. include "itkMeshFileWriter.h"
4. include "itkMeshFileReader.h"

// Create convenience typedefs const unsigned int Dimension = 3; typedef float TCoordinate;

typedef itk::Mesh< TCoordinate, Dimension > TMesh; typedef itk::RegularSphereMeshSource< TMesh > TSphere; typedef itk::MeshFileReader< TMesh > TReader; typedef itk::MeshFileWriter< TMesh > TWriter;

int main(int argc, char * argv[] ) {

 // The user can choose to provide a commandline argument
 // between 0 and 8, in order to specify the file type.
 // If no argument is provided, zero will be used.
 // If an invalid integer is provided, zero will be used.
 // If the integer is less than zero, zero will be used.
 // If the integer is greater than seven, seven will be used.
 int i = 0;
 if (argc == 2) i = atoi(argv[1]);
 i = std::max(std::min(i,8),0);

 // Create a string using the appropriate file extension.
 std::string fileName = "sphere";

 switch (i) {
   case 0: fileName += ".vtk"; break;
   case 1: fileName += ".byu"; break;
   case 2: fileName += ".fcv"; break;
   case 3: fileName += ".fsa"; break;
   case 4: fileName += ".fsb"; break;
   case 5: fileName += ".gii"; break;
   case 6: fileName += ".obj"; break;
   case 7: fileName += ".off"; break;
 }

 // Print out the file name.
 std::cout << "File Name: " << fileName << std::endl;

 // Create the sphere source, writer, and reader.
 TSphere::Pointer sphere = TSphere::New();
 TWriter::Pointer writer = TWriter::New();
 TReader::Pointer reader = TReader::New();

 // Set the writer's input and file name, then update.
 writer->SetInput( sphere->GetOutput() );
 writer->SetFileName( fileName );
 writer->Update();

 // Set the reader's file name, then update.
 reader->SetFileName( fileName );
 reader->Update();

 return EXIT_SUCCESS;

}

</source>

CMakeLists.txt

<syntaxhighlight lang="cmake"> cmake_minimum_required(VERSION 3.9.5)

project(ReadWrite)

find_package(ITK REQUIRED) include(${ITK_USE_FILE}) if (ITKVtkGlue_LOADED)

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

endif()

add_executable(ReadWrite MACOSX_BUNDLE ReadWrite.cxx)

if( "${ITK_VERSION_MAJOR}" LESS 4 )

 target_link_libraries(ReadWrite ITKReview ${ITK_LIBRARIES})

else( "${ITK_VERSION_MAJOR}" LESS 4 )

 target_link_libraries(ReadWrite ${ITK_LIBRARIES})

endif( "${ITK_VERSION_MAJOR}" LESS 4 )

</syntaxhighlight>

Download and Build ReadWrite

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

cd ReadWrite/build

• If ITK is installed:

cmake ..

• If ITK is not installed but compiled on your system, you will need to specify the path to your ITK build:

cmake -DITK_DIR:PATH=/home/me/itk_build ..

Build the project:

make

and run it:

./ReadWrite

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

Building All of the Examples

Many of the examples in the ITK Wiki Examples Collection require VTK. You can build all of the the examples by following these instructions. If you are a new VTK user, you may want to try the Superbuild which will build a proper ITK and VTK.

ItkVtkGlue

ITK >= 4

For examples that use QuickView (which depends on VTK), you must have built ITK with Module_ITKVtkGlue=ON.

ITK < 4

Some of the ITK Examples require VTK to display the images. If you download the entire ITK Wiki Examples Collection, the ItkVtkGlue directory will be included and configured. If you wish to just build a few examples, then you will need to download ItkVtkGlue and build it. When you run cmake it will ask you to specify the location of the ItkVtkGlue binary directory.