[Paraview] Problem with temporal filter and multi-block data

[Christian Wellmann]

Hi all,

I use paraview to view results of transient combined finite discrete
element analyses.
My *.pvd input files look like this:

<?xml version="1.0"?>
<VTKFile type="Collection" version="0.1" byte_order="LittleEndian">
<Collection>
<DataSet timestep="0,0000000000e+00" group="0" part="0"
file="se_relax_p_000000000.vtp"/>
<DataSet timestep="0,0000000000e+00" group="0" part="1"
file="se_relax_c_000000000.vtp"/>
<DataSet timestep="0,0000000000e+00" group="0" part="2"
file="se_relax_r_000000000.vtp"/>
<DataSet timestep="0,0000000000e+00" group="0" part="3"
file="se_relax_f_000000000.vtu"/>
<DataSet timestep="1,0000000000e-03" group="0" part="0"
file="se_relax_p_000002000.vtp"/>
<DataSet timestep="1,0000000000e-03" group="0" part="1"
file="se_relax_c_000002000.vtp"/>
.
.
.

The results are stored for each part (DE, contact, rigid-boundaries,
FE) and time step in a single *.vtp / *.vtu file.
I can load the *.pvd file into paraview apply non-temporal filters to
the single parts and animate without problems.
Now I wrote a temporal filter to show the trajectories of data points.
It requires a time series of datasets
with constant number of points and generates the trajectories of the
points as a single PolyData.
The filter works fine if my input does not consist of multiple parts:

<?xml version="1.0"?>
<VTKFile type="Collection" version="0.1" byte_order="LittleEndian">
<Collection>
<DataSet timestep="0,0000000000e+00" group="0" part="0"
file="se_relax_p_000000000.vtp"/>
<DataSet timestep="1,0000000000e-03" group="0" part="0"
file="se_relax_p_000002000.vtp"/>
<DataSet timestep="2,0000000000e-03" group="0" part="0"
file="se_relax_p_000004000.vtp"/>
.
.
.

But if I load my complete data with multiple parts and apply the
ExtractBlock filter first to show the
trajectories for one part only, ParaView complains:

ERROR: In /home/wellmann/program/ParaView-3.4.0/VTK/Filtering/vtkDemandDrivenPipeline.cxx,
line 822
vtkCompositeDataPipeline (0x1e6bbc0): Input for connection index 0 on
input port index 0 for algorithm vtkExtractBlock(0x11f4ddc0) is of
type vtkTemporalDataSet, but a vtkMultiBlockDataSet is required.

In writing the filter I tried to follow the "Time Dependent Processing
in a Parallel Pipeline Architecture" paper
and was geared to the vtkTemporalInterpolation filter. However I am
not confident about how this temporal
stuff works out: In my understanding my filter tells the upstream part
of the pipeline to loop over the requested
time steps and join the data into a TemporalDataSet that my
vtkTrajectories filter can work with. Indeed if I connect
any non temporal filter to the upstream pipeline part (instead of the
vtkTrajectories filter) I can animate over the time-steps
so the upstream pipeline is able to provide data sets for each time
step. Furthermore, as said above, the filter works
fine if there is no multiblock data as source of the pipeline.

Thanks for any hints, Christian
(the filter files are attached)

-- 
Christian Wellmann
Institute of Continuum Mechanics
Leibniz Universitaet Hannover
Appelstr. 11
30167 Hannover, Germany
phone: +49 511 762 2285
fax: +49 511 762 5496
email: wellmann at ikm.uni-hannover.de
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Trajectories.xml
Type: text/xml
Size: 1985 bytes
Desc: not available
URL: <http://www.paraview.org/pipermail/paraview/attachments/20090529/9a0d5a7b/attachment.bin>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: vtkTrajectories.cxx
Type: text/x-c++src
Size: 9716 bytes
Desc: not available
URL: <http://www.paraview.org/pipermail/paraview/attachments/20090529/9a0d5a7b/attachment.cxx>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: vtkTrajectories.h
Type: text/x-chdr
Size: 1811 bytes
Desc: not available
URL: <http://www.paraview.org/pipermail/paraview/attachments/20090529/9a0d5a7b/attachment.h>