ImageTracerWidgetInsideContour
vtk-examples/Cxx/Widgets/ImageTracerWidgetInsideContour
Question
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Code¶
ImageTracerWidgetInsideContour.cxx
#include <vtkCallbackCommand.h>
#include <vtkImageAccumulate.h>
#include <vtkImageActor.h>
#include <vtkImageCanvasSource2D.h>
#include <vtkImageData.h>
#include <vtkImageMapper3D.h>
#include <vtkImageStencilToImage.h>
#include <vtkImageTracerWidget.h>
#include <vtkInteractorStyleImage.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyData.h>
#include <vtkPolyDataToImageStencil.h>
#include <vtkPolygon.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <array>
#include <iostream>
#include <string>
namespace {
void CallbackFunction(vtkObject* caller, long unsigned int eventId,
void* clientData, void* callData);
void CreateImage1(vtkImageData*);
} // namespace
int main(int, char*[])
{
vtkNew<vtkNamedColors> colors;
vtkNew<vtkImageData> image;
CreateImage1(image);
vtkNew<vtkImageActor> actor;
actor->GetMapper()->SetInputData(image);
vtkNew<vtkRenderer> renderer;
renderer->AddActor(actor);
renderer->SetBackground(colors->GetColor3d("DarkSlateGray").GetData());
renderer->ResetCamera();
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
renderWindow->SetWindowName("ImageTracerWidgetInsideContour");
vtkNew<vtkRenderWindowInteractor> interactor;
interactor->SetRenderWindow(renderWindow);
vtkNew<vtkInteractorStyleImage> style;
interactor->SetInteractorStyle(style);
vtkNew<vtkImageTracerWidget> tracer;
tracer->GetLineProperty()->SetLineWidth(5);
tracer->SetInteractor(interactor);
tracer->SetViewProp(actor);
tracer->AutoCloseOn();
renderWindow->Render();
// The observer must be added BEFORE the On() call.
vtkNew<vtkCallbackCommand> callback;
callback->SetCallback(CallbackFunction);
callback->SetClientData(image);
tracer->AddObserver(vtkCommand::EndInteractionEvent, callback);
tracer->On();
interactor->Start();
return EXIT_SUCCESS;
}
namespace {
void CallbackFunction(vtkObject* caller, long unsigned int vtkNotUsed(eventId),
void* clientData, void* vtkNotUsed(callData))
{
vtkImageTracerWidget* tracerWidget =
static_cast<vtkImageTracerWidget*>(caller);
vtkNew<vtkPolyData> path;
if (!tracerWidget->IsClosed())
{
std::cout << "Path not closed!" << std::endl;
return;
}
tracerWidget->GetPath(path);
std::cout << "There are " << path->GetNumberOfPoints()
<< " points in the path." << std::endl;
vtkImageData* image = static_cast<vtkImageData*>(clientData);
vtkNew<vtkPolyDataToImageStencil> polyDataToImageStencil;
polyDataToImageStencil->SetTolerance(0);
polyDataToImageStencil->SetInputData(path);
polyDataToImageStencil->SetOutputOrigin(image->GetOrigin());
polyDataToImageStencil->SetOutputSpacing(image->GetSpacing());
polyDataToImageStencil->SetOutputWholeExtent(image->GetExtent());
polyDataToImageStencil->Update();
vtkNew<vtkImageStencilToImage> imageStencilToImage;
imageStencilToImage->SetInputConnection(
polyDataToImageStencil->GetOutputPort());
imageStencilToImage->SetInsideValue(255);
imageStencilToImage->Update();
vtkNew<vtkImageAccumulate> imageAccumulate;
imageAccumulate->SetStencilData(polyDataToImageStencil->GetOutput());
imageAccumulate->SetInputData(image);
imageAccumulate->Update();
std::cout << "Voxel count: " << imageAccumulate->GetVoxelCount() << std::endl;
// vtkNew<vtkPNGWriter> writer;
// writer->SetFileName("selection.png");
// writer->SetInputConnection(imageStencilToImage->GetOutputPort());
// writer->Write();
}
void CreateImage1(vtkImageData* image)
{
vtkNew<vtkNamedColors> colors;
std::array<double, 3> drawColor1{0, 0, 0};
std::array<double, 3> drawColor2{0, 0, 0};
auto color1 = colors->GetColor3ub("DarkGray").GetData();
for (auto i = 0; i < 3; ++i)
{
drawColor1[i] = color1[i];
}
vtkNew<vtkImageCanvasSource2D> imageSource;
imageSource->SetScalarTypeToUnsignedChar();
imageSource->SetNumberOfScalarComponents(1);
imageSource->SetExtent(0, 20, 0, 50, 0, 0);
imageSource->SetDrawColor(drawColor1.data());
imageSource->FillBox(0, 20, 0, 50);
imageSource->Update();
image->ShallowCopy(imageSource->GetOutput());
}
} // end anonymous namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(ImageTracerWidgetInsideContour)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "ImageTracerWidgetInsideContour: Unable to find the VTK build folder.")
endif()
# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(ImageTracerWidgetInsideContour MACOSX_BUNDLE ImageTracerWidgetInsideContour.cxx )
target_link_libraries(ImageTracerWidgetInsideContour PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS ImageTracerWidgetInsideContour
MODULES ${VTK_LIBRARIES}
)
Download and Build ImageTracerWidgetInsideContour¶
Click here to download ImageTracerWidgetInsideContour and its CMakeLists.txt file. Once the tarball ImageTracerWidgetInsideContour.tar has been downloaded and extracted,
cd ImageTracerWidgetInsideContour/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:
./ImageTracerWidgetInsideContour
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.