1.原理分析
对你的三维图形，使用一个平面切下去，然后保留一半。
确定一个平面：使用法向量和一个三维坐标点可以确定一个平面
原始图像
切一刀
切两刀，又一半
切三刀，又一半
源代码
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkClipClosedSurface.h>
#include <vtkDataSetMapper.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPlane.h>
#include <vtkPlaneCollection.h>
#include <vtkPolyData.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkXMLPolyDataReader.h>int main(int argc, char* argv[])
{vtkNew<vtkNamedColors> colors;// PolyData to processvtkSmartPointer<vtkPolyData> polyData;if (argc > 1){vtkNew<vtkXMLPolyDataReader> reader;reader->SetFileName(argv[1]);reader->Update();polyData = reader->GetOutput();}else{// Create a spherevtkNew<vtkSphereSource> sphereSource;sphereSource->SetThetaResolution(20);sphereSource->SetPhiResolution(11);sphereSource->Update();polyData = sphereSource->GetOutput();}auto center = polyData->GetCenter();vtkNew<vtkPlane> plane1;plane1->SetOrigin(center[0], center[1], center[2]);plane1->SetNormal(0.0, -1.0, 0.0);vtkNew<vtkPlane> plane2;plane2->SetOrigin(center[0], center[1], center[2]);plane2->SetNormal(0.0, 0.0, 1.0);vtkNew<vtkPlane> plane3;plane3->SetOrigin(center[0], center[1], center[2]);plane3->SetNormal(-1.0, 0.0, 0.0);vtkNew<vtkPlaneCollection> planes;planes->AddItem(plane1);planes->AddItem(plane2);planes->AddItem(plane3);vtkNew<vtkClipClosedSurface> clipper;clipper->SetInputData(polyData);clipper->SetClippingPlanes(planes);clipper->SetActivePlaneId(2);clipper->SetScalarModeToColors();clipper->SetClipColor(colors->GetColor3d("Banana").GetData());clipper->SetBaseColor(colors->GetColor3d("Tomato").GetData());clipper->SetActivePlaneColor(colors->GetColor3d("SandyBrown").GetData());vtkNew<vtkDataSetMapper> clipMapper;clipMapper->SetInputConnection(clipper->GetOutputPort());vtkNew<vtkActor> clipActor;clipActor->SetMapper(clipMapper);clipActor->GetProperty()->SetColor(1.0000, 0.3882, 0.2784);clipActor->GetProperty()->SetInterpolationToFlat();// Create graphics stuff//vtkNew<vtkRenderer> ren1;ren1->SetBackground(colors->GetColor3d("SteelBlue").GetData());vtkNew<vtkRenderWindow> renWin;renWin->AddRenderer(ren1);renWin->SetSize(512, 512);renWin->SetWindowName("ClipClosedSurface");vtkNew<vtkRenderWindowInteractor> iren;iren->SetRenderWindow(renWin);// Add the actors to the renderer, set the background and size//ren1->AddActor(clipActor);// Generate an interesting view//ren1->ResetCamera();ren1->GetActiveCamera()->Azimuth(120);ren1->GetActiveCamera()->Elevation(30);ren1->GetActiveCamera()->Dolly(1.0);ren1->ResetCameraClippingRange();renWin->Render();iren->Initialize();iren->Start();return EXIT_SUCCESS;
}
