VTK 实例50：计算三角网络模型的测地距离

#include "vtkAutoInit.h" 
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkSphereSource.h>
#include <vtkProperty.h>
#include <vtkPolyData.h>
#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkDijkstraGraphGeodesicPath.h>

int main(int , char *[])
{ 
    vtkSmartPointer<vtkSphereSource> sphereSource = 
        vtkSmartPointer<vtkSphereSource>::New();
    sphereSource->Update();

    vtkSmartPointer<vtkDijkstraGraphGeodesicPath> dijkstra = 
        vtkSmartPointer<vtkDijkstraGraphGeodesicPath>::New();
    dijkstra->SetInputData(sphereSource->GetOutput());
    dijkstra->SetStartVertex(0);
    dijkstra->SetEndVertex(10);
    dijkstra->Update();

    vtkSmartPointer<vtkPolyDataMapper> pathMapper = 
        vtkSmartPointer<vtkPolyDataMapper>::New();
    pathMapper->SetInputData(dijkstra->GetOutput());

    vtkSmartPointer<vtkActor> pathActor = 
        vtkSmartPointer<vtkActor>::New();
    pathActor->SetMapper(pathMapper);
    pathActor->GetProperty()->SetColor(1,0,0); 
    pathActor->GetProperty()->SetLineWidth(4);

    vtkSmartPointer<vtkPolyDataMapper> mapper = 
        vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputData(sphereSource->GetOutput());

    vtkSmartPointer<vtkActor> actor = 
        vtkSmartPointer<vtkActor>::New();
    actor->SetMapper(mapper);

    vtkSmartPointer<vtkRenderer> renderer = 
        vtkSmartPointer<vtkRenderer>::New();
    renderer->AddActor(actor);
    renderer->AddActor(pathActor);
    renderer->SetBackground(1.0, 1.0, 1.0); 

    vtkSmartPointer<vtkRenderWindow> renderWindow = 
        vtkSmartPointer<vtkRenderWindow>::New();
    renderWindow->AddRenderer(renderer);
    renderWindow->SetSize( 640, 480 );
    renderWindow->Render();
    renderWindow->SetWindowName("PolyDataGeodesic");

    vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = 
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
    renderWindowInteractor->SetRenderWindow(renderWindow);

    renderWindow->Render();
    renderWindowInteractor->Start();

    return EXIT_SUCCESS;
}