CheckerboardWidget
VTKExamples/Cxx/Widgets/CheckerboardWidget
Description¶
Compare two images with a checkerboard. The widget permits interactive control of the number of checkers in the x/y directions. Checkerboards are often used to compare the results of image registration. For an alternative image comparison widget try the RectilinearWipeWidget.
Question
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Code¶
CheckerboardWidget.cxx
#include <vtkSmartPointer.h> #include <vtkCheckerboardWidget.h> #include <vtkCheckerboardRepresentation.h> #include <vtkJPEGReader.h> #include <vtkImageCheckerboard.h> #include <vtkImageActor.h> #include <vtkImageMapper3D.h> #include <vtkImageData.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkProperty2D.h> #include <vtkCommand.h> #include <vtkInteractorStyleImage.h> #include <vtkNamedColors.h> int main( int argc, char *argv[] ) { if ( argc < 3 ) { std::cerr << "Usage: " << argv[0] << " Input1Filename Input2Filename" << std::endl; return EXIT_FAILURE; } //Read the images vtkSmartPointer<vtkJPEGReader> reader1 = vtkSmartPointer<vtkJPEGReader>::New(); reader1->SetFileName ( argv[1] ); vtkSmartPointer<vtkJPEGReader> reader2 = vtkSmartPointer<vtkJPEGReader>::New(); reader2->SetFileName ( argv[2] ); // Create a checker pipeline vtkSmartPointer<vtkImageCheckerboard> checker = vtkSmartPointer<vtkImageCheckerboard>::New(); checker->SetInputConnection(0,reader1->GetOutputPort()); checker->SetInputConnection(1,reader2->GetOutputPort()); checker->SetNumberOfDivisions(3,3,1); // Create the RenderWindow, Renderer and both Actors // vtkSmartPointer<vtkNamedColors> colors = vtkSmartPointer<vtkNamedColors>::New(); vtkSmartPointer<vtkRenderer> ren1 = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renWin = vtkSmartPointer<vtkRenderWindow>::New(); renWin->AddRenderer(ren1); vtkSmartPointer<vtkRenderWindowInteractor> iren = vtkSmartPointer<vtkRenderWindowInteractor>::New(); iren->SetRenderWindow(renWin); vtkSmartPointer<vtkImageActor> checkerActor = vtkSmartPointer<vtkImageActor>::New(); checkerActor->GetMapper()->SetInputConnection(checker->GetOutputPort()); // VTK widgets consist of two parts: the widget part that handles // event processing; and the widget representation that defines how // the widget appears in the scene // (i.e., matters pertaining to geometry). vtkSmartPointer<vtkCheckerboardWidget> checkerWidget = vtkSmartPointer<vtkCheckerboardWidget>::New(); checkerWidget->SetInteractor(iren); vtkCheckerboardRepresentation *checkerWidgetRep= static_cast<vtkCheckerboardRepresentation *> (checkerWidget->GetRepresentation()); checkerWidgetRep->SetImageActor(checkerActor); checkerWidgetRep->SetCheckerboard(checker); // Add the actors to the renderer, set the background and size // ren1->AddActor(checkerActor); ren1->SetBackground(colors->GetColor3d("Wheat").GetData()); renWin->SetSize(300, 300); // render the image // iren->Initialize(); renWin->Render(); checkerWidget->On(); iren->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR) project(CheckerboardWidget) find_package(VTK COMPONENTS vtkCommonColor vtkCommonCore vtkCommonDataModel vtkIOImage vtkImagingGeneral vtkInteractionStyle vtkInteractionWidgets vtkRenderingCore vtkRenderingFreeType vtkRenderingOpenGL2 QUIET) if (NOT VTK_FOUND) message("Skipping CheckerboardWidget: ${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(CheckerboardWidget MACOSX_BUNDLE CheckerboardWidget.cxx ) target_link_libraries(CheckerboardWidget PRIVATE ${VTK_LIBRARIES}) else () # include all components add_executable(CheckerboardWidget MACOSX_BUNDLE CheckerboardWidget.cxx ) target_link_libraries(CheckerboardWidget PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS CheckerboardWidget MODULES ${VTK_LIBRARIES} ) endif ()
Download and Build CheckerboardWidget¶
Click here to download CheckerboardWidget and its CMakeLists.txt file. Once the tarball CheckerboardWidget.tar has been downloaded and extracted,
cd CheckerboardWidget/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:
./CheckerboardWidget
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.