On Thu, 2009-07-02 at 16:41 -0400, Berk Geveci wrote: > OK, I think I understand now. This should work irrespective of ParaView > version: > > - Turn off "Interpolate Scalars" > - Change Interpolation to Flat >
Yep - this only works in CVS and was a reason for my confusion. I still wonder who noticed it as the ML archives go silent about it. > It is possible that there was some bug that prevented something from > working before. > > If you have cell centered data, ParaView should never interpolate > colors. Can you send me instructions to reproduce this? > Use the dataset I sent you. Apply pointDataToCellData. Cut to you liking. Observe the interpolation. D0minik > -berk > > > On Thu, Jul 2, 2009 at 9:41 AM, Dominik Szczerba<[email protected]> wrote: > > Berk, > > > > Example data: http://otoro.itis.ethz.ch/~dominik/tmp/head_eye.vti > > > > The data is point-centered. I was raising up a question if I should not > > store my label fields (from segmentation) as cell centered StructureGrid > > instead, because PV interpolates the colors regardless of the states of > > 'interpolate colors / Goraud/Flat'. But the PV-CVS is no longer > > interpolating integer point data (still insensitive to the mentioned > > states). So something changed (for good), I was asking what and why. > > > > As to the contour filter - contouring such (point based) label field > > results in an unstructured grid, so for arbitrary angles the voxel > > structure is anyway lost, thus interpolation makes sense. If however > > switched off it seems to correctly show (crippled) triangles. > > > > However, converting point data to cell data on my label field above > > results in interpolation again, that can not be switched off - probably > > because some interpolation is used during the transfer. So something is > > probably still not OK here. > > > > So a bottom line: is it finally OK to store label fields as ImageData > > (where only POINT_DATA is allowed) or do I take StructuredGrid instead > > and store the labels explicitly as CELL_DATA? > > > > regards, > > Dominik > > > > On Thu, 2009-07-02 at 09:09 -0400, Berk Geveci wrote: > >> This confuses me. The slice filter (vtkCutter) is not supposed to > >> interpolate any cell-centered data whether it is integer or double. To > >> my knowledge, there has been no bug that changed this. Can you send me > >> a small dataset that I can reproduce this with? > >> > >> -berk > >> > >> On Thu, Jul 2, 2009 at 8:12 AM, Dominik Szczerba<[email protected]> > >> wrote: > >> > I just checked that PV from CVS addresses exactly this issue, so I am > >> > apparently not alone in my considerations. PV 3.4 will load a label > >> > field and interpolate the colors when viewing slices (thus destroying > >> > the image). PV CVS ignores interpolation settings and displays my labels > >> > correctly (without interpolation). So I assume somebody realized the > >> > problem recently too and corrected it. So I conclude that ImageData is > >> > still the right choice for discrete label fields (and not > >> > StructuredGrid), but one has to rely on the latest version. Please > >> > correct me if I am wrong. > >> > > >> > -- Dominik > >> > > >> > On Wed, 2009-07-01 at 18:07 +0200, Dominik Szczerba wrote: > >> >> When storing my label field as imagedata I get unwanted interpolation if > >> >> I e.g. cut through the volume. Switching the interpolation off results > >> >> in funny bad looking triangles. What's the best/intended/practiced way > >> >> of storing (integer) label fields? Image data is point centered while > >> >> label fields are clearly cell centered. As I see the only alternative is > >> >> StructuredGrid, but functions like contouring or resampling require > >> >> point data anyway. So what's better: store my labels as image (point) > >> >> data and compromise display (unwanted interpolation) or go for > >> >> structured grid and compromise size of the file and needed conversions > >> >> to image data anyway? > >> >> > >> >> -- Dominik > >> >> > >> >> _______________________________________________ > >> >> Powered by 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 > >> >> > >> >> Follow this link to subscribe/unsubscribe: > >> >> http://www.vtk.org/mailman/listinfo/vtkusers > >> >> > >> > > >> > _______________________________________________ > >> > Powered by 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 ParaView Wiki at: > >> > http://paraview.org/Wiki/ParaView > >> > > >> > Follow this link to subscribe/unsubscribe: > >> > http://www.paraview.org/mailman/listinfo/paraview > >> > > >> > > > > > _______________________________________________ Powered by 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 ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview
