VTK

Store Polydata Some Special polydata can’t be stored by vtkSTLWriter. The following polydata contains points and a line in its structure, it can’t be saved by vtkSTLWriter, but vtkXMLPolyDataWriter works. vtkObject::GlobalWarningDisplayOn(); int numPts = 10; vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); int offset = numPts / 4; for (int i = 0; Read more…

What does the vtkImageData look like? It has a multi-layered point set. In the following example, I show all points in a vtkImageData object in the left reader and its polydata in the right render. #define vtkSPtr vtkSmartPointer #define vtkSPtrNew(Var, Type) vtkSPtr<Type> Var = vtkSPtr<Type>::New(); unsigned char inval = 255; Read more…

I write the reason why concatenate transform and its inversed transform for offTrans in scale operation based on the article Rotate, Translate And Scale For Camera vtkSPtrNew( scaleTrans, vtkTransform ); scaleTrans->Scale( factor, factor, 1 ); scaleTrans->Update(); vtkSPtrNew( offTrans, vtkTransform ); offTrans->Concatenate( worldTrans ); offTrans->Concatenate( scaleTrans ); offTrans->Concatenate( worldInversedTrans ); offTrans->Update(); Read more…

We know that there are three ways to adjust 3D model, rotate, translate and scale. If these transforms act on camera, we will see the model stand still. The status of camera in vtk can be defined by focal point, position and viewUp, so we can change these parameters to Read more…

We create a cone and a sphere individually, then combine the cone and the sphere, show it in the middle renderer. #define vtkSPtr vtkSmartPointer #define vtkSPtrNew(Var, Type) vtkSPtr<Type> Var = vtkSPtr<Type>::New(); unsigned char inval = 255; unsigned char outval = 0; double spacingVal = 0.5; vtkSPtr<vtkImageData> ConvertPolydataToImage(vtkPolyData *polydata) { double Read more…

convert polydata to image data #include <vtkVersion.h> #include <vtkImageData.h> #include <vtkImageMapper3D.h> #include <vtkImageStencil.h> #include <vtkImageStencilData.h> #include <vtkImageToImageStencil.h> #include <vtkJPEGReader.h> #include <vtkPointData.h> #include <vtkSmartPointer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkInteractorStyleImage.h> #include <vtkRenderer.h> #include <vtkImageActor.h> #include <vtkPolyDataToImageStencil.h> #include <vtkPolyData.h> #include <vtkSTLReader.h> #include <vtkImageProperty.h> #include <vtkSphereSource.h> #define vSP vtkSmartPointer #define vSPNew(Var, Type) vSP<Type> Read more…

The article shows a way to enlarge a plane and keep its original position, scale it and translate it back. #include <iostream> #include <vtkSmartPointer.h> #include <vtkProperty.h> #include <vtkPolyData.h> #include <vtkTriangleFilter.h> #include <vtkRegularPolygonSource.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> #include <vtkInteractorStyleTrackballCamera.h> #include <vtkCamera.h> #include <vtkNamedColors.h> #include <vtkImageActor.h> Read more…

The following code comes from vtkFollower, we used it to make the original axes always face the camera. #include <iostream> #include <vtkSmartPointer.h> #include <vtkProperty.h> #include <vtkPolyData.h> #include <vtkTriangleFilter.h> #include <vtkRegularPolygonSource.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> #include <vtkInteractorStyleTrackballCamera.h> #include <vtkCamera.h> #include <vtkNamedColors.h> #include <vtkImageActor.h> #include <vtkImageViewer2.h> Read more…

The algorithm vtkOBBTree::ComputeOBB can help us to calculate the three axes defining the orientation of the OBB(oriented bounding box). It is very useful for us to get the model’s spatial features. #include <iostream> #include <vtkSmartPointer.h> #include <vtkSphereSource.h> #include <vtkActor.h> #include <vtkConeSource.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkPolyDataMapper.h> #include <vtkProperty.h> #include Read more…