<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML>
<HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<META NAME="Generator" CONTENT="MS Exchange Server version 6.5.7653.38">
<TITLE>Re: [vtkusers] vtkTemporalData</TITLE>
</HEAD>
<BODY>
<!-- Converted from text/plain format -->
<P><FONT SIZE=2>Hi Erik,<BR>
I asked the very same question a couple of months back. John Biddiscombe was<BR>
very helpful in getting me up and running. Check out this thread for more<BR>
info (more towards the end of the thread will have the info you're<BR>
interested in):<BR>
<A HREF="http://www.nabble.com/TemporalDataSet-examples-td18096276.html">http://www.nabble.com/TemporalDataSet-examples-td18096276.html</A><BR>
<BR>
Basically, it is recommended to write a reader for your original data that<BR>
handles the temporal information keys (I looked at vtkEnSightReader.cxx for<BR>
an example) in RequestData and RequestInformation or use the<BR>
vtkFileSeriesReader interface in paraview.<BR>
Gerrick<BR>
<BR>
<BR>
On 4/20/09 2:22 PM, "Erik Anderson" <eranders@sci.utah.edu> wrote:<BR>
<BR>
> Hi Everyone,<BR>
> I am trying to get some visualizations of pathlines/streaklines/etc<BR>
> out of VTK. I have some time-varying data that I have created a<BR>
> vtkTemporalDataSet out of. To do this, I use something like the<BR>
> following (in Python):<BR>
><BR>
> ds = vtk.vtkTemporalDataSet()<BR>
> ds.SetNumberOfTimeSteps(5)<BR>
> for i in range(num_time_steps):<BR>
> ds.SetTimeStep(i, data[i]) # data is a list of vtkStructuredPoints<BR>
><BR>
><BR>
> After the vtkTemporalDataSet is constructed, I would like to use the<BR>
> vtkTemporalDataSetAlgorithms using the new data as input. For instance,<BR>
> I would like to use the vtkTemporalStreamTracer in conjuction with<BR>
> vtkTemporalPathLineFilter to take advantage of the time-varying vector<BR>
> field. If I print out the vtkTemporalDataSet I generate, I get exactly<BR>
> the dataset I would expect - 5 children with the appropriate fields<BR>
> attached. However, when I use a vtkTemporalStreamTracer, with the data<BR>
> as an input and a plane used to seed the lines in the source connection,<BR>
> I get the following error:<BR>
><BR>
> vtkCompositeDataPipeline (0x6bb3890): Algorithm<BR>
> vtkTemporalStreamTracer(0x7066260) returned failure for request:<BR>
> vtkInformation (0x723ab10)<BR>
> Debug: Off<BR>
> Modified Time: 1281919<BR>
> Reference Count: 1<BR>
> Registered Events: (none)<BR>
> Request: REQUEST_UPDATE_EXTENT<BR>
> ALGORITHM_BEFORE_FORWARD: 1<BR>
> FORWARD_DIRECTION: 0<BR>
> FROM_OUTPUT_PORT: 0<BR>
><BR>
><BR>
><BR>
> ERROR: In /home/eranders/env/VTK/Parallel/vtkTemporalStreamTracer.cxx,<BR>
> line 803<BR>
> vtkTemporalStreamTracer (0x7066260): No time step info<BR>
><BR>
><BR>
> Am I forming the dataset incorrectly? I'm relatively confident that my<BR>
> pipeline is correct:<BR>
><BR>
> s = vtk.vtkTemporalStreamTracer()<BR>
> s.SetInput(ds)<BR>
> s.SetSourceConnection(seeds)<BR>
><BR>
> where seeds is a vtkPlane<BR>
><BR>
> Thanks in advance for any help!<BR>
> Erik Anderson<BR>
><BR>
> _______________________________________________<BR>
> Powered by www.kitware.com<BR>
><BR>
> Visit other Kitware open-source projects at<BR>
> <A HREF="http://www.kitware.com/opensource/opensource.html">http://www.kitware.com/opensource/opensource.html</A><BR>
><BR>
> Please keep messages on-topic and check the VTK FAQ at:<BR>
> <A HREF="http://www.vtk.org/Wiki/VTK_FAQ">http://www.vtk.org/Wiki/VTK_FAQ</A><BR>
><BR>
> Follow this link to subscribe/unsubscribe:<BR>
> <A HREF="http://www.vtk.org/mailman/listinfo/vtkusers">http://www.vtk.org/mailman/listinfo/vtkusers</A><BR>
<BR>
</FONT>
</P>
</BODY>
</HTML>