[vtkusers] Copy image data into vtkImageData from a textfile

[kenichiro yoshimi]

Hi,

Thanks for trying.
Could you confirm if out.vti is visualized properly using ParaView's
volume rendering?

Regards
2018年8月2日(木) 6:12 Lizeth Castellanos <castellanoslizan at gmail.com>:
>
> Hi,
>
> I got VTK 7.1.1 in my computer, finally! So, I have tested the two solutions that you have suggested:
> 1) using vtkProbeFilter
> 2) using vtkResampleToImage
>
> 1) I  have adjusted the image dimensions according to my own data and I am using  vtkSmartVolumeMapper, instead of vtkVolumeRaycastMapper.
> No errors are generated in the terminal. However, I have been waiting for several minutes and nothing happens.
> Do you have any idea what is wrong?
>
>
> csvfile="directory path to my csv file/sample.csv"
>
> reader = vtk.vtkDelimitedTextReader()
> reader.SetFieldDelimiterCharacters(" ")
> reader.DetectNumericColumnsOn()
> reader.SetFileName(csvfile)
> reader.MergeConsecutiveDelimitersOn()
> reader.Update()
>
> tableToPoints = vtk.vtkTableToPolyData()
> tableToPoints.SetInputConnection(reader.GetOutputPort())
> tableToPoints.SetXColumn('Field 0')
> tableToPoints.SetYColumn('Field 1')
> tableToPoints.SetZColumn('Field 2')
>
> imageData = vtk.vtkImageData()
> imageData.SetDimensions(512, 512, 192)
> imageData.SetOrigin(0.0, 0.0, 0.0)
> imageData.SetSpacing(1.0, 1.0, 1.0)
>
> probeFilter = vtk.vtkProbeFilter()
> probeFilter.SetSourceConnection(tableToPoints.GetOutputPort())
> probeFilter.SetInputData(imageData)
> probeFilter.Update()
>
> writer = vtk.vtkXMLImageDataWriter()
> writer.SetInputData(probeFilter.GetOutput())
> writer.SetFileName('out.vti')
> writer.Write()
>
> probeFilter.GetOutput().GetPointData().SetActiveScalars('Field 3')
> range = probeFilter.GetOutput().GetPointData().GetScalars().GetRange()
>
> colors = vtk.vtkNamedColors()
>
> # Create the standard renderer, render window
> # and interactor.
> ren = vtk.vtkRenderer()
>
> renWin = vtk.vtkRenderWindow()
> renWin.AddRenderer(ren)
>
> iren = vtk.vtkRenderWindowInteractor()
> iren.SetRenderWindow(renWin)
>
> # Create transfer mapping scalar value to opacity.
> opacityTransferFunction = vtk.vtkPiecewiseFunction()
> opacityTransferFunction.AddPoint(range[0], 0.0)
> opacityTransferFunction.AddPoint(range[1], 1.0)
>
> # Create transfer mapping scalar value to color.
> colorTransferFunction = vtk.vtkColorTransferFunction()
> colorTransferFunction.AddRGBPoint(range[0], 0.0, 0.0, 1.0)
> colorTransferFunction.AddRGBPoint((range[0]+range[1])*0.5, 0.0, 1.0, 0.0)
> colorTransferFunction.AddRGBPoint(range[1], 1.0, 0.0, 0.0)
>
> # The property describes how the data will look.
> volumeProperty = vtk.vtkVolumeProperty()
> volumeProperty.SetColor(colorTransferFunction)
> volumeProperty.SetScalarOpacity(opacityTransferFunction)
> volumeProperty.SetScalarOpacityUnitDistance(1.73205080757)
> volumeProperty.SetInterpolationTypeToLinear()
>
> # The mapper / ray cast function know how to render the data.
> volumeMapper = vtk.vtkSmartVolumeMapper()
> volumeMapper.SetInputConnection(probeFilter.GetOutputPort())
> volumeMapper.SetBlendModeToComposite()
>
> # 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)
>
> ren.AddVolume(volume)
>
> ren.SetBackground(colors.GetColor3d("White"))
> ren.GetActiveCamera().ParallelProjectionOn()
> ren.ResetCameraClippingRange()
> ren.ResetCamera()
>
> renWin.SetSize(600, 600)
> renWin.Render()
> iren.Start()
>
>
> 2) I have tested the vtkResampleToImage class, (the solution that you suggest at the beginning of this thread). However, I get a solid a cube as output.
> Do you have any idea why that happens?
>
> csvfile="directory path to my csv file/sample.csv"
>
> reader = vtk.vtkDelimitedTextReader()
> reader.SetFieldDelimiterCharacters(" ")
> reader.DetectNumericColumnsOn()
> reader.SetFileName(csvfile)
> reader.MergeConsecutiveDelimitersOn()
> reader.Update()
>
> tableToPoints = vtk.vtkTableToPolyData()
> tableToPoints.SetInputConnection(reader.GetOutputPort())
> tableToPoints.SetXColumn("Field 0")
> tableToPoints.SetYColumn("Field 1")
> tableToPoints.SetZColumn("Field 2")
> tableToPoints.Update()
>
> resample = vtk.vtkResampleToImage()
> resample.SetInputConnection(tableToPoints.GetOutputPort())
> resample.SetSamplingDimensions(3, 3, 3)
> resample.