I want to find the central point, not mass center, between a few points like the following image. The points are on the same plane. Find the longest axis and the orthogonal axis for the points set firstly. Compute the positive farthest point and negative farthest point for every axis. Read more…
Here are a few points like the following picture. The source code: #include <iostream> #include <vector> #include <iostream> #include <vtkPolyData.h> #include <vtkProperty.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkPlane.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkPoints.h> #include <vtkInteractorStyleTrackballCamera.h> #include “./point.hpp” #include <vtkPlane.h> #include <vtkPlaneSource.h> #include <vtkTransform.h> #define vtkSPtr vtkSmartPointer #define Read more…
The post is similar to Find Closest Plane Between Points In 3D By Levmar Algorithm. The vtkPlane in vtk9.0.2 or the newer version provides a way to calculate the fitting plane for a few points. static bool ComputeBestFittingPlane(vtkPoints* pts, double* origin, double* normal);. The origin will be the centroid of Read more…
As with 2D transforms, any 3D transformation matrix can be decomposed using SVD into a rotation, scale, and another rotation. Any symmetric 3D matrix has an eigenvalue decomposition into rotation, scale, and inverse-rotation. Finally, a 3D rotation can be decomposed into a product of 3D shear matrices. Rotate about z-axis: Read more…
The post is based on https://www.weiy.city/2021/11/vtk-rotate-vector-to-special-direction/. We will rotate the three axes of the world coordinate system to particular directions. #include <iostream> #include <vtkSmartPointer.h> #include <vtkTransform.h> #include <vtkActor.h> #include <vtkConeSource.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkPolyDataMapper.h> #include <vtkRenderWindowInteractor.h> #include <vtkAxesActor.h> #include “../point.hpp” using namespace std; double AngleBeteewnTwoVector( Point vec0, Point Read more…
Here is a convex object and an origin point outside it. is an arbitrary point in the boundary. Find the farthest point on the boundary along the vector . Name the farthest point . We get a new vector to find the farthest point on the boundary along the direction Read more…
I export scene from ParaView to get a mesh like the following image. Let’s take edge lists from different parts and form two independent meshes. #include <iostream> #include <vtkSmartPointer.h> #include <vtkSphereSource.h> #include <vtkActor.h> #include <vtkConeSource.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkPolyDataMapper.h> #include <vtkRenderWindowInteractor.h> #include <vtkCellData.h> #include <vtkNamedColors.h> #include <vtkColorTransferFunction.h> #include Read more…
If two numbers are equal and the relative positions are not changed after sorting, we think the sorting algorithm is stable. Stable sort algorithm: bubble sort, insert sort and merge sort. Unstable sort algorithm: quick sort, heap sort. Introduce an unstable sort algorithm quick sort. Its core thought is divide Read more…
typeid.name The function typeid.name can give us the information about variable. Header file: typeinfo #include <typeinfo> int main() { vector<bool> vec{ false, true }; auto ans = vec[0]; cout << typeid(ans).name() << endl; bool tmp = false; cout << typeid(tmp).name() << endl; int value = 12; cout << typeid(value).name() << Read more…