[vtkusers] Does vtk StreamLine/StreamTracer dislike vtkVoxel's?
pschmitt at gmail.com
Tue Jul 19 19:21:30 EDT 2005
I have an unstructured grid consisting of many adjacent vtkVoxels
(cubes) with 8 vertices with one scalar and one vector corresponding
to every vertex.
In both Paraview and a custom VTK app, I can visualize a vectorfield.
Here's a snapshot of a sampling of the vectors:
However, I am having problems getting streamlines working in both
paraview and a custom vtk app: vtkStreamTracer and vtkStreamLine
create no streamlines whatsoever.
I can compile my code without errors or warnings, but no streamlines
are displayed to the screen. On execution, I get the following
Warning: In /software/linux-sles8-ia32/vizdev/vtk-nvgl-mpi-4.4.2-gcc-r1/src/Graphics/vtkRibbonFilter.cxx,
vtkRibbonFilter (0x8112c28): No input data!
I have tried variations of all the vtkStreamTracer and vtkStreamLine
examples and tests (sometimes using vtkRibbonFilter and sometimes
vtkTubeFilter), but the same thing happens: no streamlines! The
program loads up very quickly (as in it doesn't seem to be doing much
computation as I would expect to create streamlines). Am I having
difficulties because I store my data as voxels of an unstructured
grid? (I don't think so since the vtkStream* classes take vtkDataSet
vtkUnstructuredGrid* ugrid = vtkUnstructuredGrid::New()
//load data into vtkUnstrucutredGrid...
vtkRungeKutta4* integ = vtkRungeKutta4::New();
vtkPointSource* seeds = vtkPointSource::New();
seeds->SetCenter(140.784, 57.6672, -2.98392); //note: this point
is in my dataset!
vtkStreamTracer* streamer = vtkStreamTracer::New();
vtkRibbonFilter* rf = vtkRibbonFilter::New();
vtkPolyDataMapper* mapStream = vtkPolyDataMapper::New();
vtkActor* streamActor = vtkActor::New();
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