ExtractSelectionUsingCells选择和提取三维模型中的特定单元（Cell）

一：主要的知识点

1、说明

本文只是教程内容的一小段，因博客字数限制，故进行拆分。主教程链接：vtk教程——逐行解析官网所有Python示例-CSDN博客

2、知识点纪要

本段代码主要涉及的有①通过特定索引取得网格面模型

二：代码及注释

import vtkmodules.vtkRenderingOpenGL2 from vtkmodules.vtkCommonColor import vtkNamedColors from vtkmodules.vtkCommonCore import vtkIdTypeArray from vtkmodules.vtkCommonDataModel import vtkSelection, vtkSelectionNode, vtkUnstructuredGrid from vtkmodules.vtkFiltersExtraction import vtkExtractSelection from vtkmodules.vtkFiltersSources import vtkSphereSource from vtkmodules.vtkRenderingCore import ( vtkActor, vtkCamera, vtkDataSetMapper, vtkProperty, vtkRenderWindow, vtkRenderWindowInteractor, vtkRenderer ) def main(): colors = vtkNamedColors() sphereSource = vtkSphereSource() sphereSource.Update() ids = vtkIdTypeArray() ids.SetNumberOfComponents(1) for i in range(10, 20): ids.InsertNextValue(i) selectionNode = vtkSelectionNode() selectionNode.SetFieldType(vtkSelectionNode.CELL) selectionNode.SetSelectionList(ids) selectionNode.SetContentType(vtkSelectionNode.INDICES) selection = vtkSelection() selection.AddNode(selectionNode) extractSelection = vtkExtractSelection() extractSelection.SetInputConnection(0, sphereSource.GetOutputPort()) extractSelection.SetInputData(1, selection) extractSelection.Update() selected = vtkUnstructuredGrid() selected.ShallowCopy(extractSelection.GetOutput()) selectionNode.GetProperties().Set(vtkSelectionNode.INVERSE(), 1) #取反，1表示取反状态启用？ extractSelection.Update() notSelected = vtkUnstructuredGrid() notSelected.ShallowCopy(extractSelection.GetOutput()) backfaces = vtkProperty() backfaces.SetColor(colors.GetColor3d("Gold")) inputMapper = vtkDataSetMapper() inputMapper.SetInputConnection(sphereSource.GetOutputPort()) inputActor = vtkActor() inputActor.SetMapper(inputMapper) inputActor.GetProperty().SetColor(colors.GetColor3d("MistyRose")) inputActor.SetBackfaceProperty(backfaces) selectedMapper = vtkDataSetMapper() selectedMapper.SetInputData(selected) selectedActor = vtkActor() selectedActor.SetMapper(selectedMapper) selectedActor.SetBackfaceProperty(backfaces) selectedActor.GetProperty().SetColor(colors.GetColor3d('MistyRose')) notSelectedMapper = vtkDataSetMapper() notSelectedMapper.SetInputData(notSelected) notSelectedActor = vtkActor() notSelectedActor.SetMapper(notSelectedMapper) notSelectedActor.SetBackfaceProperty(backfaces) notSelectedActor.GetProperty().SetColor(colors.GetColor3d('MistyRose')) # There will be one render window renderWindow = vtkRenderWindow() renderWindow.SetSize(900, 300) renderWindow.SetWindowName('ExtractSelectionCells') # And one interactor interactor = vtkRenderWindowInteractor() interactor.SetRenderWindow(renderWindow) # Define viewport ranges # (xmin, ymin, xmax, ymax) leftViewport = [0.0, 0.0, 0.33, 1.0] centerViewport = [0.33, 0.0, 0.66, 1.0] rightViewport = [0.66, 0.0, 1.0, 1.0] # Create a camera for all renderers camera = vtkCamera() # Setup the renderers leftRenderer = vtkRenderer() renderWindow.AddRenderer(leftRenderer) leftRenderer.SetViewport(leftViewport) leftRenderer.SetBackground(colors.GetColor3d('BurlyWood')) leftRenderer.SetActiveCamera(camera) centerRenderer = vtkRenderer() renderWindow.AddRenderer(centerRenderer) centerRenderer.SetViewport(centerViewport) centerRenderer.SetBackground(colors.GetColor3d('orchid_dark')) centerRenderer.SetActiveCamera(camera) rightRenderer = vtkRenderer() renderWindow.AddRenderer(rightRenderer) rightRenderer.SetViewport(rightViewport) rightRenderer.SetBackground(colors.GetColor3d('CornflowerBlue')) rightRenderer.SetActiveCamera(camera) leftRenderer.AddActor(inputActor) centerRenderer.AddActor(selectedActor) rightRenderer.AddActor(notSelectedActor) leftRenderer.ResetCamera() renderWindow.Render() interactor.Start() if __name__ == '__main__': main()