In the mesh structure of 3D models, there is a kind of situation that can make many 3D algorithms useless or even break down. Because the default input model for many 3D algorithms is a manifold structure. But sometimes we get a data that is not manifold. The left side Read more…
The post shows how to use blender to create a lock model simply. youtube bilibili The STL file in the video can be downloaded by the link: https://www.jianguoyun.com/p/DaPwDyAQjNHfCRijhp4E
Here is a way to remesh 3D model, for every edge we can add a few points on it and create new small cells. The old big triangle will be removed from the model.
Generate a new polyData which has not invalid point. We have to colloct the points that are used by cells and update the point ids in the cell lists. I used binary search algorithm to speed up the process.
We have to find all edges and judge whether the point is in the circumscribed sphere of another three points, the target edge is used by two cells, it has only one neighbor cell in the other words. Finally, flip the cells as the above image.
But the result of the cutting is not particularly idealistic.
So we have to increase density necessarily.
The left one is the low density model, the right attachment model has higher density in the following image.
The post shows how to display the normals of cells on the 3D model by ParaView.
The general steps are in the demo video.
1. Clip model for better watching
2. Add normals filter
3. Show wireframe for better watching
Here is a video to show how to change the density of model by MeshMixer, then compare the new model and old model in ParaView. The general steps are in the following part.
The article shows a few tips in VTK development. There are simple tasks for most developers but the functions can be used in many situations. Convert the length value in the display coordinate system to the new value in the world coordinate system. double DisplayLenToWorldLen(const double &length) { Point p0( Read more…