VTK/Examples/Cxx/Broken/PolyData/DeleteCells
From KitwarePublic
Delete a cell from vtkPolyData
This example demonstrates how to delete a cell from a vtkPolyData. This is a three-step process: first, build upward-links from points to cells; second, mark cells for deletion; third, delete the marked cells. The first step is necessary to create a data structure suitable for efficient delete operations. Creating this data structure is computationally expensive, so it is only carried out before operations that need it, e.g. those that require changes to the topology.
DeleteCells.cxx
#include <vtkActor.h> #include <vtkCellArray.h> #include <vtkLine.h> #include <vtkPoints.h> #include <vtkPolyData.h> #include <vtkPolyDataMapper.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkSmartPointer.h> int main(int, char *[]) { vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); points->InsertNextPoint(0,0,0); points->InsertNextPoint(1,0,0); points->InsertNextPoint(1,1,0); points->InsertNextPoint(0,1,0); vtkSmartPointer<vtkLine> line0 = vtkSmartPointer<vtkLine>::New(); line0->GetPointIds()->SetId(0, 0); line0->GetPointIds()->SetId(1, 1); vtkSmartPointer<vtkLine> line1 = vtkSmartPointer<vtkLine>::New(); line1->GetPointIds()->SetId(0, 1); line1->GetPointIds()->SetId(1, 2); vtkSmartPointer<vtkLine> line2 = vtkSmartPointer<vtkLine>::New(); line2->GetPointIds()->SetId(0, 2); line2->GetPointIds()->SetId(1, 3); vtkSmartPointer<vtkCellArray> lines = vtkSmartPointer<vtkCellArray>::New(); lines->InsertNextCell(line0); lines->InsertNextCell(line1); lines->InsertNextCell(line2); vtkSmartPointer<vtkPolyData> polydata = vtkSmartPointer<vtkPolyData>::New(); polydata->SetPoints(points); polydata->SetLines(lines); // Tell the polydata to build 'upward' links from points to cells. polydata->BuildLinks(); // Mark a cell as deleted. polydata->DeleteCell(1); // Remove the marked cell. polydata->RemoveDeletedCells(); // Visualize vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New(); mapper->SetInputConnection(polydata->GetProducerPort()); vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New(); actor->SetMapper(mapper); vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer(renderer); vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); renderWindowInteractor->SetRenderWindow(renderWindow); renderer->AddActor(actor); renderWindow->Render(); renderWindowInteractor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt
PROJECT(FilledContours) CMAKE_MINIMUM_REQUIRED(VERSION 2.6) FIND_PACKAGE(VTK REQUIRED) INCLUDE(${VTK_USE_FILE}) ADD_EXECUTABLE(DeleteCells DeleteCells.cxx) TARGET_LINK_LIBRARIES(DeleteCells vtkHybrid)
