Hello everyone,
I’m working with vtk 8.2 on Windows 10 with VS 2017.
I try to create a closed Spline around the contour of a binary image in purpose to change the value of each pixels inside the closed spline.
To do this, I use vtkMarchingSquares to extract the contour of the binary image.
After that, I try to put the points from the output polydata of the vtkMarchingSquares but the spline is not set at the expected position.
I’m not sure what I did wrong. Maybe there is too much points on the contour?
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkSplineWidget2.h>
#include <vtkSplineWidget.h>
#include <vtkCardinalSpline.h>
#include <vtkKochanekSpline.h>
#include <vtkParametricSpline.h>
#include <vtkImageData.h>
#include <vtkPointData.h>
#include <vtkDataSetMapper.h>
#include <vtkProperty.h>
#include <vtkImageActor.h>
#include <vtkContourFilter.h>
#include <vtkPolyData.h>
#include <vtkCellData.h>
#include <vtkDataArray.h>
#include <vtkCellArray.h>
#include <vtkPolyDataMapper.h>
#include <vtkMarchingSquares.h>
#include <vtkImageStack.h>
#include <vtkSplineRepresentation.h>
int main(int, char *[])
{
vtkNew<vtkImageData> image;
image->SetDimensions(512, 512, 2);
image->SetOrigin(0, 0, 0);
image->SetSpacing(0.97, 0.97, 1);
image->AllocateScalars(VTK_SHORT, 1);
for (int k = 0; k < 2; ++k)
{
for (int j = 0; j < 512; ++j)
{
for (int i = 0; i < 512; ++i)
{
short * pixel = static_cast<short *>(image->GetScalarPointer(i, j, k));
if (i > 100 && i < 300 && j > 100 && j < 300)
{
pixel[0] = 255;
}
else
{
pixel[0] = 0;
}
}
}
}
vtkNew<vtkMarchingSquares> contourFilter;
contourFilter->SetInputData(image);
contourFilter->GenerateValues(1, 255, 255);
contourFilter->Update();
vtkSmartPointer<vtkPolyData> contourPolyData = contourFilter->GetOutput();
// vtkNew<vtkDataSetMapper> imageMapper;
// imageMapper->SetInputData(image);
vtkNew<vtkImageActor> imageActor;
imageActor->SetInputData(image);
vtkNew<vtkPolyDataMapper> contourMapper;
contourMapper->SetInputData(contourPolyData);
vtkNew<vtkActor> contourActor;
contourActor->SetMapper(contourMapper);
contourActor->GetProperty()->SetLineWidth(2);
contourActor->GetProperty()->SetColor(1, 0, 0);
// A renderer and render window
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
// An interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
vtkNew<vtkParametricSpline> parametricSpline;
parametricSpline->SetPoints(contourPolyData->GetPoints());
vtkNew<vtkSplineRepresentation> splineRepresentation;
splineRepresentation->SetParametricSpline(parametricSpline);
vtkNew<vtkKochanekSpline> xSpline;
vtkNew<vtkKochanekSpline> ySpline;
vtkNew<vtkKochanekSpline> zSpline;
splineRepresentation->GetParametricSpline()->SetXSpline(xSpline);
splineRepresentation->GetParametricSpline()->SetYSpline(ySpline);
splineRepresentation->GetParametricSpline()->SetZSpline(zSpline);
splineRepresentation->GetParametricSpline()->SetPoints(contourPolyData->GetPoints());
splineRepresentation->ClosedOn();
vtkSmartPointer<vtkSplineWidget2> splineWidget =
vtkSmartPointer<vtkSplineWidget2>::New();
splineWidget->SetRepresentation(splineRepresentation);
splineWidget->SetInteractor(renderWindowInteractor);
renderWindowInteractor->Initialize();
renderWindow->Render();
splineWidget->On();
renderer->AddActor(imageActor);
renderer->ResetCamera();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
