[vtkusers] Fwd: vtkOpenGLProjectedTetrahedraMapper vs vtkUnstructuredGridVolumeRayCastMapper

[Artem Babayan]

Hello,

I have the following situation:

1) 3D scalar field defined on non-uniform Cartesian grid is read from
.vtk  file with vtkStructuredPointsReader
2) Read data then fed to to vtkDataSetTriangleFilter
3) Color and opacity map are set.
4) 3D filed is visualised using vtkUnstructuredGridVolumeRayCastMapper
or vtkOpenGLProjectedTetrahedraMapper or OpenGLHAVSVolumeMapper

As a result -- I've got 3 completely different pictures (attached 1st
for  vtkUnstructuredGridVolumeRayCastMapper, 2nd for
vtkOpenGLProjectedTetrahedraMapper and 3rd for vtkOpenGLHAVSVolumeMapper)
-- ignore the blocks as they are irrelevant here. Why is it so and
which one is correct? It looks like at least vtkOpenGLHAVSVolumeMapper
cannot 'see'
values below certain level.

If it is of any help -- the data range is from 1e-25 to 14.0 and the
non-uniform Cartesian grid is non-uniform in z-direction only.
The grid size are the following: dx==dy==25 , dz[] = {0, 4, 12, 30,
70, 150, 290, 670, 1020}

Best wishes
Artem
-------------- next part --------------
A non-text attachment was scrubbed...
Name: picVolumeRay.png
Type: image/png
Size: 45876 bytes
Desc: not available
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20100609/fefd41e5/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: picGLProjected.png
Type: image/png
Size: 115549 bytes
Desc: not available
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20100609/fefd41e5/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: picGLHAVS.png
Type: image/png
Size: 9265 bytes
Desc: not available
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20100609/fefd41e5/attachment-0002.png>