Here are two methods used to sample points on a model (surface mesh or 3D polydata). Filter connected points Use BFS (Breadth First Search) algorithm to get connected points in polyData. Iterate through all the points in jumps to achieve the purpose of sampling. Sampling points by spatial distance Calculate Read more…
Oringial scene: The right polyData has shallowCopyed the left one. If A had ShallowCopyed B in VTK project, A and B were both vtkPolyData objects, let’s change A’s point or change its pointData scalar, B’s point and scalar will also be changed. If we use `rightPolydata->GetPointData()->SetScalars( scalars1 );` to change Read more…
I added two renderers in renderWindow, and set a blue background for the top renderer. But the color is not visible, here is source code. We can find the description for the usage of the interface SetPreserveColorBuffer. Add the following code for renderer2. We can see the blue background of the Read more…
If you have used vtkImageActor or vtkImageMapper + vtkActor2D to display an image in VTK renderer window, you can change the value of ColorLevel of vtkImageMapper to adjust the exposure to get a better effect. As the ColorLevel value increases, the exposure decreases while the ColorWindow value remains constant.
Here is a simple example about make vtkImageActor always face current active camera and keep it under a vtkFollower object. It’s impossible to send image data to vtkFollower directly, so we have to add the feature that adjust orientation of image actor automatically when rendering. To keep the lower status, Read more…
We can find that vtkImageActor object will display image with controling its position with the bottom left corner of the image by the default way. Test project: Result: How to make the image’s center as actor’s position? Just as rewrite 3D model to make center as (0,0,0), related post: https://www.weiy.city/2022/01/rewrite-file-to-move-3d-model-to-origin-point/ Read more…
The post shows a way to remesh a model to make uneven triangles on the mesh to be more uniform. The 3D model file locker.stl can be downloaded at the page:https://www.weiy.city/downloads/3d-model-simple-lock/ . Compare the original mesh and the new data in paraview:
I found an interesting issue about vtkSDL2OpenGLRenderWindow::SetSize when changed canvas for VTK WASM 3D window.The related post on the website is Change Canvas For VTK WASM Project. The interface SetSize can work if it was used before m_RenderWindowInteractor->SetRenderWindow( newWin );.It means the 3D window will become smaller or bigger than the outer shell. The red object Read more…