ReadUnstructuredGrid
vtk-examples/Cxx/IO/ReadUnstructuredGrid
Description¶
This example demonstrates how to read an unstructured grid (VTU) file. The front facing faces are colored Misty Rose, while the back facing faces are colored Tomato.
An example file to use is src/Testing/Data/tetra.vtu
.
Question
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Code¶
ReadUnstructuredGrid.cxx
#include <vtkActor.h>
#include <vtkDataSetMapper.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkXMLUnstructuredGridReader.h>
int main(int argc, char* argv[])
{
// parse command line arguments
if (argc < 2)
{
std::cerr << "Usage: " << argv[0] << " Filename(.vtu) e.g. tetra.vtu"
<< std::endl;
return EXIT_FAILURE;
}
std::string filename = argv[1];
// read all the data from the file
vtkNew<vtkXMLUnstructuredGridReader> reader;
reader->SetFileName(filename.c_str());
reader->Update();
vtkNew<vtkNamedColors> colors;
// Create a mapper and actor
vtkNew<vtkDataSetMapper> mapper;
mapper->SetInputConnection(reader->GetOutputPort());
mapper->ScalarVisibilityOff();
vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
actor->GetProperty()->EdgeVisibilityOn();
actor->GetProperty()->SetLineWidth(2.0);
actor->GetProperty()->SetColor(colors->GetColor3d("MistyRose").GetData());
vtkNew<vtkProperty> backFace;
backFace->SetColor(colors->GetColor3d("Tomato").GetData());
actor->SetBackfaceProperty(backFace);
// Create a renderer, render window, and interactor
vtkNew<vtkRenderer> renderer;
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
renderWindowInteractor->SetRenderWindow(renderWindow);
// Add the actor to the scene
renderer->AddActor(actor);
renderer->SetBackground(colors->GetColor3d("Wheat").GetData());
// Render and interact
renderWindow->SetSize(640, 480);
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(ReadUnstructuredGrid)
find_package(VTK COMPONENTS
vtkCommonColor
vtkCommonCore
vtkIOXML
vtkInteractionStyle
vtkRenderingContextOpenGL2
vtkRenderingCore
vtkRenderingFreeType
vtkRenderingGL2PSOpenGL2
vtkRenderingOpenGL2
QUIET
)
if (NOT VTK_FOUND)
message("Skipping ReadUnstructuredGrid: ${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(ReadUnstructuredGrid MACOSX_BUNDLE ReadUnstructuredGrid.cxx )
target_link_libraries(ReadUnstructuredGrid PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(ReadUnstructuredGrid MACOSX_BUNDLE ReadUnstructuredGrid.cxx )
target_link_libraries(ReadUnstructuredGrid PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS ReadUnstructuredGrid
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build ReadUnstructuredGrid¶
Click here to download ReadUnstructuredGrid and its CMakeLists.txt file. Once the tarball ReadUnstructuredGrid.tar has been downloaded and extracted,
cd ReadUnstructuredGrid/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:
./ReadUnstructuredGrid
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.