They are many different cells in VTK, they can be divided into two kinds, linear cells, and non-linear cells. The following images are from VTKUsersGuide. Linear Cells Non-Linear Cells Although vtkUnstructuredGrid and vtkPolyData are similar, there are substantial differences. vtkPolyData can only represent cells of topological dimension 2 or less Read more…
Here is relevant introduction about vtkImageData from VTKUsersGuide. A vtkImageData dataset is defined by data dimensions, interpoint spacing, and the origin (i.e., lower-left corner) of the dataset. If the dimension of the dataset is two, then we call the vtkImageData dataset an image, and it is composed of vtkPixel cell Read more…
Last night I read some pages in VTKUsersGuide to learn VTK factory mechanism. I got the basic steps of defining my own factory and use it. Implement virtual function which is declared in vtkObjectFactory. virtual const char* GetVTKSourceVersion(); virtual const char* GetDescription(); Create Object Use the protected function RegisterOverride which Read more…
Development environment: VTK-8.1.1 To observe all details during rotating the cone, I put a axes actor and another same size cone on the same initial position. So it looks that there is only one cone but that’s not the truth. The two cones are located in the center [0, 0, Read more…
I want to put a spline widget on a plane and move the control points to show scalar on different position dynamically. It will be convenient for user to check the change of scalar on the model. It’s easy to use vtkStructuredGrid and vtkGeometryFilter to create a plane with color Read more…
A few macros we need in our project are in the following code snippet. They can make our project cleaner. #define vtkPtr( var, className ) vtkSmartPointer<className> var = \ vtkSmartPointer<className>::New() #define CPP_SET_MACRO(name,type) \ void Set##name(type _arg) \ { \ if (this->name != _arg) \ { \ this->name = _arg; \ Read more…
VTK provides some convenient algorithms to help us display the whole digital elevation model (DEM). My university major is Geometry Information Science, it’s so exciting for me to write an article about DEM since I became a professional software develop programmer. In the following section, I will show how to Read more…
vtkImageActor vtkImageActor is used to display picture in 3D render window. By changing the interactor to a vtkInteractorStyleImage you can limit rotations so that user can operate the 3D render window as a 2D image viewer. python code: import vtk fileName = “/Users/weiyang/Desktop/Untitled.png” reader = vtk.vtkPNGReader() reader.SetFileName( fileName ) reader.Update() Read more…
vtkBoxWidget2 shows a bounding box outline, the face of the box can be picked and moved to scale the object inside the bounding box. After rotating, translating, and scaling, we can ensure the inside item change shape and position with the box widget. It sounds so good that user can Read more…