SelectWindowRegion
VTKEx/Cxx/Visualization/SelectWindowRegion
Question
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Code¶
SelectWindowRegion.cxx
#include <vtkSmartPointer.h>
#include <vtkCallbackCommand.h>
#include <vtkCommand.h>
#include <vtkImageActor.h>
#include <vtkImageMapper3D.h>
#include <vtkInteractorStyleRubberBand2D.h>
#include <vtkJPEGReader.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
static void SelectionChangedCallbackFunction (
vtkObject* caller,
long unsigned int eventId,
void* clientData,
void* callData );
int main(int argc, char* argv[])
{
// Parse input arguments
if ( argc != 2 )
{
std::cout << "Required parameters: Filename" << std::endl;
return EXIT_FAILURE;
}
std::string inputFilename = argv[1];
// Read the image
vtkSmartPointer<vtkJPEGReader> jPEGReader =
vtkSmartPointer<vtkJPEGReader>::New();
jPEGReader->SetFileName ( inputFilename.c_str() );
jPEGReader->Update();
// Create an actor
vtkSmartPointer<vtkImageActor> actor =
vtkSmartPointer<vtkImageActor>::New();
actor->GetMapper()->SetInputConnection ( jPEGReader->GetOutputPort() );
// Setup the SelectionChangedEvent callback
vtkSmartPointer<vtkCallbackCommand> selectionChangedCallback =
vtkSmartPointer<vtkCallbackCommand>::New();
selectionChangedCallback->SetCallback ( SelectionChangedCallbackFunction );
// Setup renderer
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
renderer->AddActor ( actor );
renderer->ResetCamera();
// Setup render window
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer ( renderer );
// Setup 2D interaction style
vtkSmartPointer<vtkInteractorStyleRubberBand2D> style =
vtkSmartPointer<vtkInteractorStyleRubberBand2D>::New();
style->AddObserver ( vtkCommand::SelectionChangedEvent, selectionChangedCallback );
// Setup render window interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetInteractorStyle ( style );
// Render and start interaction
renderWindowInteractor->SetRenderWindow ( renderWindow );
renderWindow->Render();
renderWindowInteractor->Initialize();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
void SelectionChangedCallbackFunction (
vtkObject* vtkNotUsed(caller),
long unsigned int vtkNotUsed(eventId),
void* vtkNotUsed(clientData),
void* callData )
{
std::cout << "Selection changed callback" << std::endl;
unsigned int* rect = reinterpret_cast<unsigned int*> ( callData );
unsigned int pos1X = rect[0];
unsigned int pos1Y = rect[1];
unsigned int pos2X = rect[2];
unsigned int pos2Y = rect[3];
std::cout << "Start x: " << pos1X
<< " Start y: " << pos1Y
<< " End x: " << pos2X
<< " End y: " << pos2Y << std::endl;
}
/*
//You could override this, but then you have to reimplement the functionality.
//Instead, you should use an observer
void vtkInteractorStyleRubberBand2D::OnLeftButtonUp()
{
std::cout << "LeftButtonUp!" << std::endl;
std::cout << "Start: " << this->StartPosition[0] << " " << this->StartPosition[1] << std::endl;
std::cout << "End: " << this->EndPosition[0] << " " << this->EndPosition[1] << std::endl;
//this->Superclass.OnLeftButtonUp(); //doesn't work
InvokeEvent(vtkCommand::EndPickEvent);
InvokeEvent(vtkCommand::SelectionChangedEvent);
}
*/
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(SelectWindowRegion)
find_package(VTK COMPONENTS
vtkvtkCommonCore
vtkvtkIOImage
vtkvtkInteractionStyle
vtkvtkRenderingContextOpenGL2
vtkvtkRenderingCore
vtkvtkRenderingFreeType
vtkvtkRenderingGL2PSOpenGL2
vtkvtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
message("Skipping SelectWindowRegion: ${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(SelectWindowRegion MACOSX_BUNDLE SelectWindowRegion.cxx )
target_link_libraries(SelectWindowRegion PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(SelectWindowRegion MACOSX_BUNDLE SelectWindowRegion.cxx )
target_link_libraries(SelectWindowRegion PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS SelectWindowRegion
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build SelectWindowRegion¶
Click here to download SelectWindowRegion and its CMakeLists.txt file. Once the tarball SelectWindowRegion.tar has been downloaded and extracted,
cd SelectWindowRegion/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:
./SelectWindowRegion
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.