[vtkusers] Many VTK build tests fail when run from Jenkins/Bamboo or VNC display, even when DISPLAY is set to good opengl-enabled display

[Ben Boeckel]

On Sat, Dec 23, 2017 at 00:13:50 +1030, John wrote:
> Perhaps the reason these tests are failing is obvious to someone with a
> more knowledge of the testing process?

I don't know how mcuh I'd be able to help, but if you could submit an
experimental run to CDash and link to it, it'd make it easier to see
what's common between the failing tests.

FWIW, we do have a few machines using VNC for their testing, but they're
currently only testing ParaView. One is `megas` which tests Catalyst and
the other is `pvbinsdash` which is working on the ParaView superbuild.
Historically, `megas` also had VTK builds on it, but other than volume
rendering tests (due to Fedora's Mesa not supporting floating point
textures), some others were excluded mentioning "broken selection on
VNC", "broken transparency on VNC(?)", and "broken stencil buffer on
VNC(?)":

  - TestYoungsMaterialInterface
  - TestWindowToImageTransparency
  - rendererSource

--Ben