Use Transform We have both points on the image, the distance weight on the x-axis between the two points is 1. What is the distance weight on the vector (p1−p2) between the two points? It’s easy to calculate the result because we know Pythagorean theorem and the special direction is Read more…
I don’t know the difference between center and origin in vtkPlane when I use it in my project for the first time. I thought the center of the plane is its origin until today, it’s the reason why I could not get a correct rectangle when I tried to set Read more…
The library OpenCTM can be used to compress 3D data files. The new compressed file has only about 1/10 size compared with the original file. We can use vertex property to store the model’s color which is often PointData’s scalar in VTK. The following code snippet shows how to use Read more…
The vtkCamera object has a front clipping plane and back clipping plane. Users can only see the middle part between the clipping planes. So we can change the clipping plane's position, clipping range, to get a different 3D scene. The relevant variable in VTK is double vtkCamera: ClippingRange[2];. When we Read more…
The algorithm class vtkPolyDataNormals can be used to calculate normals of points and cells in polydata. The following example shows how to use it. Cube Create a cube in which every cell is a single square. All information can be found in polydata, we use vtkPolyDataNormals to handle it and Read more…
Sometimes the 3D model and 2D object will be overlapped as the above scene. I want to move the text to the top for avoiding overlap situation. My solution has these steps: 1. Calculate the bounding box of the sphere and convert it to a rectangle which wraps the image Read more…
We can put model in VTK display coordinate system. The following example is based on a previous article: Show Special Character In VTK . I add a line which start from (0,0) to left bottom corner of red string, the line is represented as 2D model. int *size = renderer->GetSize(); Read more…
We can use vtkTextActor to show string which contains special character. I use encoding value to represent math symbol and store it in QString object in the following example. #include <vtkActor.h> #include <vtkPolyData.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkSmartPointer.h> #include <vtkTextActor.h> #include <vtkSphereSource.h> #include <vtkPlaneSource.h> #include <vtkPolyDataMapper.h> #include Read more…
After upgrade vtk from 7.1.0 to 8.2.0, the old project shows a warning window about VTKWidget. The newest vtk-qt program suggest me not to use old QVTKWidget anymore, so I rewrite my qt UI file I have qt UI file as the following code snippet, a few widgets are put Read more…