我有一个包含多个数据数组的卷,并使用vtkVolumeMapper(vtkFixedPointVolumeRayCastMapper)对其进行渲染。
我如何告诉映射器将特定数组用作标量?(SelectColorArray不是vtkVolumeMapper的函数)
我正在使用VTK 6
# Create the reader for the data
reader = vtk.vtkXMLImageDataReader()
reader.SetFileName(self.scan_analysis.content.vtk_path)
reader.GetOutput().GetPointData().SetActiveScalars('smooth')
# Create transfer mapping scalar value to opacity
opacityTransferFunction = vtk.vtkPiecewiseFunction()
opacityTransferFunction.AddPoint(5, 0.0)
opacityTransferFunction.AddPoint(80, 0.4)
opacityTransferFunction.AddPoint(81, 0.0)
opacityTransferFunction.AddPoint(100, 0.0)
# Create transfer mapping scalar value to color
lut = vtk.vtkColorTransferFunction()
lut.AddRGBPoint(0.0, 0.0, 0.0, 1.0)
lut.AddRGBPoint(50.0, 1.0, 1.0, 1.0)
lut.AddRGBPoint(100.0, 1.0, 0.0, 0.0)
# The property describes how the data will look
volumeProperty = vtk.vtkVolumeProperty()
volumeProperty.SetColor(lut)
volumeProperty.SetScalarOpacity(opacityTransferFunction)
volumeProperty.ShadeOn()
volumeProperty.SetInterpolationTypeToLinear()
# The mapper / ray cast function know how to render the data
#volumeMapper = vtk.vtkGPUVolumeRayCastMapper()
#volumeMapper = vtk.vtkSmartVolumeMapper()
volumeMapper = vtk.vtkFixedPointVolumeRayCastMapper()
volumeMapper.SetBlendModeToComposite()
volumeMapper.SetInputConnection(reader.GetOutputPort())
volumeMapper.SelectColorArray('smooth') ## -> exception
# The volume holds the mapper and the property and
# can be used to position/orient the volume
volume = vtk.vtkVolume()
volume.SetMapper(volumeMapper)
volume.SetProperty(volumeProperty)
此外,是否可以将体标量用于体积映射器?
感谢
更新:我结束了对每个标量使用不同的vtk文件。它可以工作,并且不会消耗更多的磁盘空间...但我知道这不是正确的解决方案(令人沮丧)
我使用SetScalarsName找到了以下解决方案:
from vtk import (vtkUnstructuredGridReader, vtkDataSetMapper, vtkActor,
vtkRenderer, vtkRenderWindow, vtkRenderWindowInteractor)
# Read the source file.
reader = vtkUnstructuredGridReader()
reader.SetFileName("FileName")
reader.SetScalarsName("ScalarNameYouWant") ### this command should do it
#reader.ReadAllScalarsOn()
reader.Update() # Needed because of GetScalarRange
output = reader.GetOutput()
output_port = reader.GetOutputPort()
scalar_range = output.GetScalarRange()
# Create the mapper that corresponds the objects of the vtk file
# into graphics elements
mapper = vtkDataSetMapper()
mapper.SetInputConnection(output_port)
mapper.SetScalarRange(scalar_range)
# Create the Actor
actor = vtkActor()
actor.SetMapper(mapper)
# Create the Renderer
renderer = vtkRenderer()
renderer.AddActor(actor)
renderer.SetBackground(1, 1, 1) # Set background to white
# Create the RendererWindow
renderer_window = vtkRenderWindow()
renderer_window.AddRenderer(renderer)
# Create the RendererWindowInteractor and display the vtk_file
interactor = vtkRenderWindowInteractor()
interactor.SetRenderWindow(renderer_window)
interactor.Initialize()
interactor.Start()
解决方案在这里找到:https://vtk.org/gitweb?p=VTK.git;a=blob;f=Examples/DataManipulation/Python/pointToCellData.py