[vtkusers] confused with vtkProbeFilter

[Martin Genet]

Works like a charm…thanks! Martin

On 16/05/2016 19:55, Sujin Philip wrote:
> Hi Martin,
>
> Attached is the modified script that I ran. This is the output of the 
> script:
> pointdata 1 9
> (0.0,) (0.0,) (0.0,) (0.0,) (2.0,) (0.0,) (0.0,) (0.0,) (0.0,)
> celldata 1 9
> (0.0,) (0.0,) (0.0,) (0.0,) (2.0,) (0.0,) (0.0,) (0.0,) (0.0,)
> vtkValidPointMask 1 9
> (0.0,) (0.0,) (0.0,) (0.0,) (1.0,) (0.0,) (0.0,) (0.0,) (0.0,)
>
> The results look correct. Is this not the behaviour you are getting? 
> Let me know if you still have issues.
>
> Thanks
> Sujin
>
>
> On Fri, May 13, 2016 at 7:45 PM, Martin Genet 
> <martin.genet at polytechnique.edu 
> <mailto:martin.genet at polytechnique.edu>> wrote:
>
>     Thanks for your help, Sujin.
>
>     What do you mean exactly by "your code works for me"? I sat the
>     arrays names but am still getting the same behavior: the code runs
>     fine, but I can't find the interpolated data. Do you know where it
>     is? Thanks again.
>
>     Martin
>
>
>     On 13/05/2016 18:53, Sujin Philip wrote:
>>     Hi Martin,
>>
>>     You need to set names for the point and cell data arrays.
>>     farray.SetName("pointdata") and farray.SetName("celldata")
>>
>>     after doing that your code works for me.
>>
>>     -Sujin
>>
>>
>>     On Fri, May 13, 2016 at 12:16 PM, Martin Genet
>>     <martin.genet at polytechnique.edu
>>     <mailto:martin.genet at polytechnique.edu>> wrote:
>>
>>         Dear everyone:
>>
>>         Sorry for the triviality, but I'm getting confused with
>>         vtkProbeFilter: trying to probe an image with a mesh (not the
>>         opposite: I need the mesh data interpolated onto the image
>>         points), but can't get it to work.
>>
>>         Consider the following code:
>>
>>             import numpy
>>             import vtk
>>
>>             image = vtk.vtkImageData()
>>             image.SetDimensions([3, 3, 1])
>>             image.SetSpacing(1./numpy.array(image.GetDimensions()))
>>             image.SetOrigin(numpy.array(image.GetSpacing())/2)
>>
>>             points = vtk.vtkPoints()
>>             points.InsertNextPoint([1./4, 1./4, 2./4])
>>             points.InsertNextPoint([3./4, 1./4, 2./4])
>>             points.InsertNextPoint([3./4, 3./4, 2./4])
>>             points.InsertNextPoint([1./4, 3./4, 2./4])
>>
>>             cell = vtk.vtkQuad()
>>             cell.GetPointIds().SetId(0, 0)
>>             cell.GetPointIds().SetId(1, 1)
>>             cell.GetPointIds().SetId(2, 2)
>>             cell.GetPointIds().SetId(3, 3)
>>
>>             cell_array = vtk.vtkCellArray()
>>             cell_array.InsertNextCell(cell)
>>
>>             ugrid = vtk.vtkUnstructuredGrid()
>>             ugrid.SetPoints(points)
>>             ugrid.SetCells(vtk.VTK_QUAD, cell_array)
>>
>>             farray = vtk.vtkFloatArray()
>>             farray.SetNumberOfComponents(1)
>>             farray.SetNumberOfTuples(1)
>>             farray.SetTuple1(0, 2.)
>>             ugrid.GetCellData().AddArray(farray)
>>
>>             farray = vtk.vtkFloatArray()
>>             farray.SetNumberOfComponents(1)
>>             farray.SetNumberOfTuples(4)
>>             farray.SetTuple1(0, 2.)
>>             farray.SetTuple1(2, 2.)
>>             farray.SetTuple1(3, 2.)
>>             farray.SetTuple1(4, 2.)
>>             ugrid.GetPointData().AddArray(farray)
>>
>>             probe = vtk.vtkProbeFilter()
>>             if (vtk.vtkVersion.GetVTKMajorVersion() >= 6):
>>                 probe.SetInputData(image)
>>                 probe.SetSourceData(ugrid)
>>             else:
>>                 probe.SetInput(image)
>>                 probe.SetSource(ugrid)
>>             probe.Update()
>>             probed_image = probe.GetOutput()
>>
>>
>>         Problem is: probed_image contains only one array, called
>>         vtkValidPointMask, but no interpolated data.
>>
>>         If I do:
>>
>>             probed_scalars =
>>             probed_image.GetPointData().GetArray("vtkValidPointMask")
>>             for k_voxels in
>>             xrange(probed_scalars.GetNumberOfTuples()): print
>>             probed_scalars.GetTuple1(k_voxels)
>>
>>         I'm getting:
>>
>>             0.0
>>             0.0
>>             0.0
>>             0.0
>>             1.0
>>             0.0
>>             0.0
>>             0.0
>>             0.0
>>
>>         So I'm guessing the filter is able to figure out which image
>>         point lies within the mesh and which does not, but I can't
>>         find the interpolated data? Any help would be super
>>         appreciated. Thanks!
>>
>>         Martin
>>
>>         _______________________________________________
>>         Powered by www.kitware.com <http://www.kitware.com>
>>
>>         Visit other Kitware open-source projects at
>>         http://www.kitware.com/opensource/opensource.html
>>
>>         Please keep messages on-topic and check the VTK FAQ at:
>>         http://www.vtk.org/Wiki/VTK_FAQ
>>
>>         Search the list archives at:
>>         http://markmail.org/search/?q=vtkusers
>>
>>         Follow this link to subscribe/unsubscribe:
>>         http://public.kitware.com/mailman/listinfo/vtkusers
>>
>>
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20160516/f1d8d4de/attachment.html>