VTK Non Manifold Face 삭제 코드

Non Manifold는 아래 글을 통해 설명했습니다.

2024.01.10 - [3D Algorithm] - Manifold와 Nonmanifold 차이(Mesh Processing)

Manifold와 Nonmanifold 차이(Mesh Processing)

 

VTK를 이용해서 Non Manifold face들을 삭제하는 코드는 아래와 같습니다.
face들을 삭제한 후에는 hole이 생기기 때문에 hole filling 등을 이용하여 hole을 채워줘야 합니다.

void deleteNonManifold(vtkPolyData *polydata)
{		
	vtkSmartPointer<vtkFeatureEdges> nmEdges = vtkSmartPointer<vtkFeatureEdges>::New();
	nmEdges->BoundaryEdgesOff();
	nmEdges->FeatureEdgesOff();
	nmEdges->NonManifoldEdgesOn();
	nmEdges->ManifoldEdgesOff();
	nmEdges->SetInputData(polydata);
	nmEdges->Update();

	vtkSmartPointer<vtkPolyData> nmePolyData = nmEdges->GetOutput();	
	vector<bool> flags(polydata->GetNumberOfPoints(), false);
	for (vtkIdType ptId = 0; ptId < nmePolyData->GetNumberOfPoints(); ++ptId)
	{
		double nmePnt[3];
		nmePolyData->GetPoint(ptId, nmePnt);
		vtkIdType vertId = polydata->FindPoint(nmePnt);
		if (vertId != -1)		
			flags[vertId] = true;		
	}	
	vtkSmartPointer<vtkIdList> cellIdList = vtkSmartPointer<vtkIdList>::New();
	for (vtkIdType ptId = 0; ptId < polydata->GetNumberOfPoints(); ++ptId)
	{		
		if (!flags[ptId])	continue;		
		polydata->GetPointCells(ptId, cellIdList);
		for (vtkIdType i = 0; i < cellIdList->GetNumberOfIds(); ++i)		
			polydata->DeleteCell(cellIdList->GetId(i));		
	}
	polydata->RemoveDeletedCells();
}