[Paraview] VTK warning during volume rendering of vtkStructuredGrid on Windows with Nvidia graphics card.

[Paul Mackenzie]

Hahn, Steven E. <hahnse <at> ornl.gov> writes:

> 
> I tried viewing the volume representation of a small vtkStructuredGrid
> file with ParaView v5.0.0-RC2 built with the OpenGL2 rendering backend and
> get this warning:
> 
> Warning: In 
> C:\Sources\ParaView-v5.0.0-RC1-source\VTK\Rendering\VolumeOpenGL2\vtkOpenGL
> ProjectedTetrahedraMapper.cxx, line 251
> vtkOpenGLProjectedTetrahedraMapper (00000000061B0AD0): Missing FBO
> support. The algorithm may produce visual artifacts.
> 
> Updating the video card (Nvidia Quadro K6000) driver to the latest version
> (354.56) had no effect. Volume rendering with a different vtkImageData
> file generated no warnings.
> 
> Best,
> Steven Hahn
> 
> 

I have the same problem. Though in my case it is a small unstructuredgrid
vtu file. The OS is Ubuntu 14.04. ParaView-5.0.0-Qt4-OpenGL2-MPI-Linux-64bit
prebuilt binaries. The Graphics card is Nvidia Quadro K620 with OpenGL
version 3.02 Nvidia 352.63. The Nvidia settings show the following etensions
amongst others GL_ARB_frame_buffer_object.

Also, it does show artifacts. In particular for a vector allocated to a
standard hexahedron cell, the colors are slightly different within the cell.
You can see triangular segments [possibly tetrahedron?]
Regard
Paul.