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①vtkStreamTracer流体可视化的类
二：代码及注释
import vtkmodules.vtkInteractionStyle import vtkmodules.vtkRenderingOpenGL2 from vtkmodules.vtkCommonColor import vtkNamedColors from vtkmodules.vtkCommonCore import vtkLookupTable from vtkmodules.vtkFiltersCore import vtkContourFilter, vtkThresholdPoints, vtkTubeFilter from vtkmodules.vtkIOLegacy import vtkStructuredPointsReader from vtkmodules.vtkFiltersSources import vtkPointSource from vtkmodules.vtkFiltersFlowPaths import vtkStreamTracer from vtkmodules.vtkFiltersModeling import vtkOutlineFilter from vtkmodules.vtkRenderingCore import ( vtkActor, vtkCamera, vtkPolyDataMapper, vtkRenderWindow, vtkRenderWindowInteractor, vtkRenderer ) def main(): colors = vtkNamedColors() fileName = "Data/carotid.vtk" ren1 = vtkRenderer() renWin = vtkRenderWindow() renWin.AddRenderer(ren1) iren = vtkRenderWindowInteractor() iren.SetRenderWindow(renWin) reader = vtkStructuredPointsReader() reader.SetFileName(fileName) psource = vtkPointSource() psource.SetNumberOfPoints(25) psource.SetCenter(133.1, 116.3, 5.0) psource.SetRadius(2.0) threshold = vtkThresholdPoints() threshold.SetInputConnection(reader.GetOutputPort()) threshold.ThresholdByUpper(275) """ vtkStreamTracer 流体可视化中非常重要的一个类 是用来在一个向量场（Vector Field）中追踪流线的类，功能是给定一个速度场（如流体速度、风场、磁场、电场）和一些起点（seeds）， 沿着速度方向（或反方向）积分，生成流线（streamlines）或路径线（pathlines） 输入数据： 一个 向量场（通常是 vtkStructuredPoints, vtkImageData, vtkRectilinearGrid, 或 vtkUnstructuredGrid） 种子点： 起始点的几何数据（如 vtkPointSource, vtkLineSource 等） 输出数据： 一组流线（vtkPolyData），每条流线是一条由点组成的折线 """ streamers = vtkStreamTracer() # 设置流线追踪的数据源 streamers.SetInputConnection(reader.GetOutputPort()) # 设置流线追踪的起始点 streamers.SetSourceConnection(psource.GetOutputPort()) # 限制流线长度。防止流线过长，消耗过多计算资源 streamers.SetMaximumPropagation(100.0) # 控制计算精度和速度。流线是通过数值积分计算的，步长越小，计算结果越精确 streamers.SetInitialIntegrationStep(0.2) # 定义停止时间。如果流体粒子所在位置的速度矢量大小低于这个阈值0.01，流线追踪将自动停止 streamers.SetTerminalSpeed(.01) streamers.Update() scalarRange = [0] * 2 scalarRange[0] = streamers.GetOutput().GetPointData().GetScalars().GetRange()[0] scalarRange[1] = streamers.GetOutput().GetPointData().GetScalars().GetRange()[1] print("range: ", scalarRange[0], ", ", scalarRange[1]) """ 主要作用是将3D 空间中的线条（例如流线追踪器输出的细线）转换成具有一定粗细的管状几何体， 使其在视觉上更饱满和突出 """ tubes = vtkTubeFilter() tubes.SetInputConnection(streamers.GetOutputPort()) tubes.SetRadius(0.3) tubes.SetNumberOfSides(6) """ SetVaryRadius 用来控制这些管状结构的半径是保持恒定，还是根据数据场中的某个标量值来变化 0表示半径恒定，1表示随标量变化，2随矢量变化，3随标量绝对值变化 """ tubes.SetVaryRadius(0) lut = vtkLookupTable() lut.SetHueRange(.667, 0.0) lut.Build() streamerMapper = vtkPolyDataMapper() streamerMapper.SetInputConnection(tubes.GetOutputPort()) streamerMapper.SetScalarRange(scalarRange[0], scalarRange[1]) streamerMapper.SetLookupTable(lut) streamerActor = vtkActor() streamerActor.SetMapper(streamerMapper) iso = vtkContourFilter() iso.SetInputConnection(reader.GetOutputPort()) iso.SetValue(0, 175) isoMapper = vtkPolyDataMapper() isoMapper.SetInputConnection(iso.GetOutputPort()) isoMapper.ScalarVisibilityOff() isoActor = vtkActor() isoActor.SetMapper(isoMapper) isoActor.GetProperty().SetRepresentationToWireframe() isoActor.GetProperty().SetOpacity(0.25) outline = vtkOutlineFilter() outline.SetInputConnection(reader.GetOutputPort()) outlineMapper = vtkPolyDataMapper() outlineMapper.SetInputConnection(outline.GetOutputPort()) outlineActor = vtkActor() outlineActor.SetMapper(outlineMapper) outlineActor.GetProperty().SetColor(colors.GetColor3d("Black")) # Add the actors to the renderer, set the background and size. # ren1.AddActor(outlineActor) ren1.AddActor(streamerActor) ren1.AddActor(isoActor) ren1.SetBackground(colors.GetColor3d("Wheat")) renWin.SetSize(640, 480) renWin.SetWindowName('CarotidFlow') cam1 = vtkCamera() cam1.SetClippingRange(17.4043, 870.216) cam1.SetFocalPoint(136.71, 104.025, 23) cam1.SetPosition(204.747, 258.939, 63.7925) cam1.SetViewUp(-0.102647, -0.210897, 0.972104) cam1.Zoom(1.2) ren1.SetActiveCamera(cam1) # Render the image. # renWin.Render() iren.Start() if __name__ == '__main__': main()
