VTK: 选取区域裁剪（vtkAreaPicker + vtkInteractorStyleRubberBandPick ）

简介：

1、vtkAreaPicker：获取裁剪平面

2、vtkClipClosedSurface：完成裁剪

完成代码：

#include <vtkActor.h>
#include <vtkAreaPicker.h>
#include <vtkDataSetMapper.h>
#include <vtkDataSetSurfaceFilter.h>
#include <vtkExtractPolyDataGeometry.h>
#include <vtkIdFilter.h>
#include <vtkIdTypeArray.h>
#include <vtkInteractorStyleRubberBandPick.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkObjectFactory.h>
#include <vtkPlanes.h>
#include <vtkPointData.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkRendererCollection.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkUnstructuredGrid.h>
#include <vtkVersion.h>
#include <vtkVertexGlyphFilter.h>
#include <vtkPolyDataReader.h>
#include <vtkSTLReader.h>
#include "vtkClipClosedSurface.h"
#include "vtkPlaneCollection.h"
#include "vtkAxesActor.h"
#define VTKISRBP_ORIENT 0
#define VTKISRBP_SELECT 1


namespace {
	// Define interaction style
	class HighlightInteractorStyle : public vtkInteractorStyleRubberBandPick
	{
	public:
		static HighlightInteractorStyle* New();
		vtkTypeMacro(HighlightInteractorStyle, vtkInteractorStyleRubberBandPick);

		HighlightInteractorStyle() : vtkInteractorStyleRubberBandPick()
		{
			this->SelectedMapper = vtkSmartPointer<vtkDataSetMapper>::New();
			this->SelectedActor = vtkSmartPointer<vtkActor>::New();
			this->SelectedActor->SetMapper(SelectedMapper);
		}

		virtual void OnLeftButtonUp() override
		{
			// Forward events
			vtkInteractorStyleRubberBandPick::OnLeftButtonUp();

			if (this->CurrentMode == VTKISRBP_SELECT)
			{
				vtkNew<vtkNamedColors> colors;

				vtkPlanes* frustum = static_cast<vtkAreaPicker*>(this->GetInteractor()->GetPicker())->GetFrustum();

				vtkNew<vtkPlaneCollection> planeCollection;
				int pCount = frustum->GetNumberOfPlanes() - 2;
				for (int i = 0; i < pCount; i++)
				{
					double normal[3];
					frustum->GetPlane(i)->GetNormal(normal);
					double origin[3];
					frustum->GetPlane(i)->GetOrigin(origin);

					vtkNew<vtkPlane> plane;
					plane->SetOrigin(origin[0], origin[1], origin[2]);
					plane->SetNormal(-normal[0], -normal[1], -normal[2]);
					planeCollection->AddItem(plane);
				}
				
				vtkNew<vtkClipClosedSurface> clipper;
				clipper->SetInputData(this->PolyData);
				clipper->SetClippingPlanes(planeCollection);
				clipper->Update();

				if (m_SrcActor != nullptr)
					m_SrcActor->VisibilityOff();

				this->SelectedMapper->SetInputData(clipper->GetOutput());

				this->SelectedActor->GetProperty()->SetColor(1.0000, 0.3882, 0.2784);
				this->GetInteractor()->GetRenderWindow()->GetRenderers()->GetFirstRenderer()->AddActor(SelectedActor);
				this->GetInteractor()->GetRenderWindow()->Render();
				this->HighlightProp(NULL);
			}
		}

		void SetPolyData(vtkSmartPointer<vtkPolyData> polyData)
		{
			this->PolyData = polyData;
		}
		vtkActor* m_SrcActor = nullptr;
	private:
		vtkSmartPointer<vtkPolyData> PolyData;
		vtkSmartPointer<vtkActor> SelectedActor;
		vtkSmartPointer<vtkDataSetMapper> SelectedMapper;
	};
	vtkStandardNewMacro(HighlightInteractorStyle);

} // namespace

int main(int argc, char* argv[])
{

	vtkNew<vtkSphereSource> source;
	source->SetPhiResolution(49);
	source->SetThetaResolution(200);
	source->Update();
	auto polyData = source->GetOutput();


	// Create a mapper and actor
	vtkNew<vtkPolyDataMapper> mapper;
	mapper->SetInputData(polyData);
	mapper->ScalarVisibilityOff();

	vtkNew<vtkActor> actor;
	actor->SetMapper(mapper);
	actor->GetProperty()->SetPointSize(5);

	vtkNew<vtkAxesActor> axes;
	// Visualize
	vtkNew<vtkRenderer> renderer;
	renderer->UseHiddenLineRemovalOn();

	vtkNew<vtkRenderWindow> renderWindow;
	renderWindow->AddRenderer(renderer);
	renderWindow->SetSize(640, 480);
	renderWindow->SetWindowName("HighlightSelection");

	vtkNew<vtkAreaPicker> areaPicker;
	vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
	renderWindowInteractor->SetPicker(areaPicker);
	renderWindowInteractor->SetRenderWindow(renderWindow);

	renderer->AddActor(actor);
	renderer->AddActor(axes);

	renderWindow->Render();

	vtkNew<HighlightInteractorStyle> style;
	style->m_SrcActor = actor;
	style->SetPolyData(polyData);
	style->SetCurrentRenderer(renderer);
	renderWindowInteractor->SetInteractorStyle(style);

	renderWindowInteractor->Start();

	return EXIT_SUCCESS;
}