鼠标点击位置获取几何体对象_vtkAreaPicker_vtkInteractorStyleRubberBandPick

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开发环境：

1. Windows 11 家庭中文版
2. Microsoft Visual Studio Community 2019
3. VTK-9.3.0.rc0
4. vtk-example
5. 参考代码

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demo解决问题：框选或者点选某一区域，并获取区域prop3D对象（红线内为有效区域，polydata组成的3d几何对象）

1. vtkInteractorStyleRubberBandPick

  /*与TrackBallCamera类似，但是它可以选择橡皮筋选择矩形下面的道具。该交互器样式允许用户通过按下'r'并使用左鼠标按钮在渲染窗口中绘制矩形。当释放鼠标按钮时，附加的拾取器将在选择矩形中心的像素上操作。如果拾取器恰好是vtkAreaPicker，则它将在整个选择矩形上操作。当按下'p'键时，上述拾取操作在1x1矩形上发生。在其他方面，它的行为与其父类相同。另请参见vtkAreaPicker*/// r使能或禁用区域框选，框选区域中pick有效区域// For vtkInteractorStyleRubberBandPick - use 'r' and left-mouse to draw a// selection box used to pick.// // p按下时，pick当前鼠标位置所在的区域// For vtkInteractorStyleTrackballCamera - use 'p' to pick at the current// mouse position.vtkNew<vtkInteractorStyleRubberBandPick> style;

2. vtkAreaPicker

	vtkNew<vtkAreaPicker> areaPicker;vtkNew<vtkCallbackCommand> pickCallback;pickCallback->SetCallback(PickCallbackFunction);areaPicker->AddObserver(vtkCommand::EndPickEvent, pickCallback);

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prj name: AreaPicking

#include <vtkActor.h>
#include <vtkAreaPicker.h>
#include <vtkCallbackCommand.h>
#include <vtkCellArray.h>
#include <vtkInteractorStyleRubberBandPick.h>
#include <vtkInteractorStyleTrackball.h>
// #include <vtkInteractorStyleTrackballCamera.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPoints.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProp3DCollection.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>namespace {
void PickCallbackFunction(vtkObject* caller, long unsigned int eventId,void* clientData, void* callData);
}int main(int, char*[])
{// Create a set of points.vtkNew<vtkPoints> points;vtkNew<vtkCellArray> vertices;vtkIdType pid[1];pid[0] = points->InsertNextPoint(1.0, 0.0, 0.0);vertices->InsertNextCell(1, pid);pid[0] = points->InsertNextPoint(0.0, 0.0, 0.0);vertices->InsertNextCell(1, pid);pid[0] = points->InsertNextPoint(0.0, 1.0, 0.0);vertices->InsertNextCell(1, pid);// Create a polydatavtkNew<vtkPolyData> polydata;polydata->SetPoints(points);polydata->SetVerts(vertices);// VisualizevtkNew<vtkPolyDataMapper> mapper;mapper->SetInputData(polydata);vtkNew<vtkNamedColors> colors;vtkNew<vtkActor> actor;actor->SetMapper(mapper);actor->GetProperty()->SetPointSize(8);                                //设置顶点的显示大小actor->GetProperty()->SetColor(colors->GetColor3d("Gold").GetData()); //设置顶点的显示颜色vtkNew<vtkRenderer> renderer;vtkNew<vtkRenderWindow> renderWindow;renderWindow->AddRenderer(renderer);renderWindow->SetWindowName("AreaPicking");vtkNew<vtkAreaPicker> areaPicker;vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;renderWindowInteractor->SetRenderWindow(renderWindow);renderWindowInteractor->SetPicker(areaPicker);renderer->AddActor(actor);renderer->SetBackground(colors->GetColor3d("DarkSlateGray").GetData());renderWindow->Render();// r使能或禁用区域框选，框选区域中pick有效区域// For vtkInteractorStyleRubberBandPick - use 'r' and left-mouse to draw a// selection box used to pick.vtkNew<vtkInteractorStyleRubberBandPick> style;// p按下时，pick当前鼠标位置所在的区域// For vtkInteractorStyleTrackballCamera - use 'p' to pick at the current// mouse position.//  vtkNew<vtkInteractorStyleTrackballCamera> style;//    paraviewstyle->SetCurrentRenderer(renderer);renderWindowInteractor->SetInteractorStyle(style);vtkNew<vtkCallbackCommand> pickCallback;pickCallback->SetCallback(PickCallbackFunction);areaPicker->AddObserver(vtkCommand::EndPickEvent, pickCallback);renderWindowInteractor->Start();return EXIT_SUCCESS;
}namespace {
void PickCallbackFunction(vtkObject* caller,long unsigned int vtkNotUsed(eventId),void* vtkNotUsed(clientData),void* vtkNotUsed(callData))
{std::cout << "Pick." << std::endl;vtkAreaPicker* areaPicker = static_cast<vtkAreaPicker*>(caller);vtkProp3DCollection* props = areaPicker->GetProp3Ds();props->InitTraversal();//遍历当权pick到那些区域（Prop3Ds）for (vtkIdType i = 0; i < props->GetNumberOfItems(); i++){vtkProp3D* prop = props->GetNextProp3D();std::cout << "Picked prop: " << prop << std::endl;}
}
} // namespace