VTK读取stl文件用D算法计算指定两点之间的最短路径经过的点

转载：https://blog.csdn.net/wolfcsharp/article/details/84886128
基本流程：
(1)读入stl文件
(2)设置起点，终点
(3)计算最短路径
(4)打印一条最短路径经过的所有点的索引
(5)在原三维结构中画出最短路径并显示

#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);

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

int main()
{
	//读取stl文件
	std::string inputFilename = "line.stl";

	vtkSmartPointer<vtkSTLReader> reader = vtkSmartPointer<vtkSTLReader>::New();
	reader->SetFileName(inputFilename.c_str());
	reader->Update();
	
	//设置起点终点，D算法求解最短路径
	vtkSmartPointer<vtkDijkstraGraphGeodesicPath> dijstra = vtkSmartPointer<vtkDijkstraGraphGeodesicPath>::New();
	dijstra->SetInputData(reader->GetOutput());
	dijstra->SetStartVertex(0);
	dijstra->SetEndVertex(16);
	dijstra->Update();

	//打印最短路径的索引号
	//D算法求解后，dijstra->GetIdList()可以得到完整的最短路径的索引，提取这些点的索引号必须再用一个for对IdList->GetId(i)进行提取
	vtkSmartPointer<vtkIdList> IdList = vtkSmartPointer<vtkIdList>::New();
	IdList = dijstra->GetIdList();
	for (int i = 0; i < IdList->GetNumberOfIds(); i++)
	{
		cout << IdList->GetId(i) << endl;
	}
	
	//在原三维结构中画出最短路径并显示
	vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
	mapper->SetInputData(reader->GetOutput());
	vtkSmartPointer<vtkPolyDataMapper> pathMapper = vtkSmartPointer<vtkPolyDataMapper>::New();
	pathMapper->SetInputData(dijstra->GetOutput());

	vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
	actor->SetMapper(mapper);
	vtkSmartPointer<vtkActor> pathActor = vtkSmartPointer<vtkActor>::New();
	pathActor->SetMapper(pathMapper);
	pathActor->GetProperty()->SetColor(1, 0, 0);
	pathActor->GetProperty()->SetLineWidth(5);

	vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
	renderer->AddActor(actor);
	renderer->AddActor(pathActor);
	renderer->SetBackground(0, 0, 0);

	vtkSmartPointer<vtkRenderWindow> rw = vtkSmartPointer<vtkRenderWindow>::New();
	rw->AddRenderer(renderer);
	rw->SetSize(640, 480);
	rw->SetWindowName("Calculating Geodesic Path");

	vtkSmartPointer<vtkRenderWindowInteractor> rwi = vtkSmartPointer<vtkRenderWindowInteractor>::New();
	rwi->SetRenderWindow(rw);
	rwi->Initialize();
	rwi->Start();

	return 0;
}