TensorGlyph
VTKExamples/Cxx/Visualization/TensorGlyph
Description¶
This example demonstrates how to apply a rotation+scaling matrix to each point in a data set. We use a cube as the glyph so that simple rotations are easy to interpret. Specifically, we glyph one point with no rotation/scaling, and a second point with a rotation of 45 degrees around the x axis.
Code¶
TensorGlyph.cxx
#include <vtkVersion.h> #include <vtkActor.h> #include <vtkCellArray.h> #include <vtkDoubleArray.h> #include <vtkMath.h> #include <vtkPointData.h> #include <vtkPoints.h> #include <vtkPointSource.h> #include <vtkPolyDataMapper.h> #include <vtkPolyData.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkSmartPointer.h> #include <vtkCubeSource.h> #include <vtkTensorGlyph.h> #include <vtkVertexGlyphFilter.h> int main(int, char *[]) { // Setup points vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); points->InsertNextPoint(0.0, 0.0, 0.0); points->InsertNextPoint(5.0, 0.0, 0.0); vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New(); polyData->SetPoints(points); vtkSmartPointer<vtkDoubleArray> tensors = vtkSmartPointer<vtkDoubleArray>::New(); tensors->SetNumberOfTuples(2); tensors->SetNumberOfComponents(9); tensors->InsertTuple9(0,1,0,0,0,1,0,0,0,1); tensors->InsertTuple9(1,1,0,0,0,.7,.7,0,-.7,.7); // column major polyData->GetPointData()->SetTensors(tensors); vtkSmartPointer<vtkCubeSource> cubeSource = vtkSmartPointer<vtkCubeSource>::New(); cubeSource->Update(); vtkSmartPointer<vtkTensorGlyph> tensorGlyph = vtkSmartPointer<vtkTensorGlyph>::New(); #if VTK_MAJOR_VERSION <= 5 tensorGlyph->SetInput(polyData); #else tensorGlyph->SetInputData(polyData); #endif tensorGlyph->SetSourceConnection(cubeSource->GetOutputPort()); tensorGlyph->ColorGlyphsOff(); tensorGlyph->ThreeGlyphsOff(); tensorGlyph->ExtractEigenvaluesOff(); tensorGlyph->Update(); vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New(); #if VTK_MAJOR_VERSION <= 5 mapper->SetInput(tensorGlyph->GetOutput()); #else mapper->SetInputData(tensorGlyph->GetOutput()); #endif vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New(); actor->SetMapper(mapper); vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); renderer->AddActor(actor); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer( renderer ); vtkSmartPointer<vtkRenderWindowInteractor> interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); interactor->SetRenderWindow( renderWindow ); renderWindow->Render(); interactor->Start(); return 0; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(TensorGlyph) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(TensorGlyph MACOSX_BUNDLE TensorGlyph.cxx) target_link_libraries(TensorGlyph ${VTK_LIBRARIES})
Download and Build TensorGlyph¶
Danger
The generation of tar files has not been ported to the new VTKExamples. Some tarballs may be missing or out-of-date.
Click here to download TensorGlyph and its CMakeLists.txt file. Once the tarball TensorGlyph.tar has been downloaded and extracted,
cd TensorGlyph/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:
./TensorGlyph
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.