VTK – Page 9 – weiy.city

3D – Rotate Axis System To The Special Orientation

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…

By StephenWei, 3 years ago

Math

VTK – Rotate Vector To Special Direction

I take notes about how to rotate vector to a special direction. #include “./tool.h” #define vtkSPtr vtkSmartPointer #define vtkSPtrNew(Var, Type) vtkSPtr<Type> Var = vtkSPtr<Type>::New(); int main(int, char *[]) { PointStruct vec0( 1, 1, 0 ); PointStruct vec1( -1, 1, 0 ); PointStruct vecZ( 0, 0, 1 ); double radian = Read more…

By StephenWei, 3 years ago

VTK

Learn VTK By Python Script On Mac

The post introduces how to create an environment for learning VTK by Python. The basic conditions on my computer: VTK-8.1.1 macOS Mojave 10.14 Python 2.7.10 Write a bash script and run it. cmake ./ -G “Unix Makefiles” \ -DVTK_USE_QVTK:BOOL=ON \ -DCMAKE_INSTALL_PREFIX=/usr/local \ -DVTK_USE_GUISUPPORT:BOOL=ON \ -DVTK_QT_VERSION=5 \ -DModule_vtkGUISupportQt:BOOL=ON \ -DModule_vtkGUISupportQtOpenGL:BOOL=ON \ Read more…

By StephenWei, 3 years ago

VTK

Create 2D Grid On Screen By VTK

The post shows a way to create 2D grid on screen by VTK. Show it by vtkActor2D because we regard it as a 2D object. Its default coordinate system is viewport which is rendering. So we will have to know the window’s size. Let’s make the process easier. Change the Read more…

By StephenWei, 3 years2021-09-28 ago

Math

Check Whether Point Is Inside The Polygon / Circle

I created a 2D convex hull and wanted to check whether a point is inside it. If the point is inside the polygon, the neighbor cross product vectors have the same directions. If the point is outside, one vector is toward the outside, the other one is toward the inside. Read more…

By StephenWei, 3 years2021-09-26 ago

VTK

Find 2D Convex Hull And 3D Convex Hull By VTK

The post shows how to find 2D convex hull and 3D convex hull from points cloud by VTK. Here are some points on screen, finally I add a specail point that z value is not 0 for test 3D convex hull. #include <iostream> #include <vtkSmartPointer.h> #include <vtkSphereSource.h> #include <vtkActor.h> #include Read more…

By StephenWei, 3 years2021-09-26 ago

Algorithm

VTK – Separating Meshe By Connectivity

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…

By StephenWei, 3 years ago

VTK

VTK – Set Position For vtkTextActor

The article discuss an issue about set position for vtkTextActor object. The class vtkTextActor provides interface SetPosition, its parameter controls object’s left-bottom coordinate. /** * Get the PositionCoordinate instance of vtkCoordinate. * This is used for for complicated or relative positioning. * The position variable controls the lower left corner Read more…

By StephenWei, 3 years ago

VTK

VTK Boolean operation – The Notes About Logic Subtraction For Mesh

We often subtract mesh by other object to get the result we want. The scene looks like the following image. #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 <vtkClipPolyData.h> #include <vtkImplicitBoolean.h> #include <vtkPlanes.h> #include <vtkDataArray.h> #include <vtkDoubleArray.h> #include <vtkProperty.h> Read more…

By StephenWei, 3 years2021-09-19 ago