[vtkusers] Display Error under Ubuntu 16.04

[Andrea Borsic]

Dear All,

I have successfully compiled VTK 7.0.0  under Ubuntu 16.04.1 LTS on a 
computer with the following hw configuration:

Processor: Intel Core i7

GPU: NVIDIA GTX Titan Black

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VTK has been configured for:

OpenGL 2 back-end

Use Qt 5.7

Use OpenMP for SMP

Wrap Python 3 (ver 3.5.2 on the system)

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A simple python script which displays an unstructured grid and which 
works fine under Windows, opens (under Ubuntu) a rendering window and 
crashes with the message below:

X Error of failed request:  GLXBadDrawable
   Major opcode of failed request:  154 (GLX)
   Minor opcode of failed request:  11 (X_GLXSwapBuffers)
   Serial number of failed request:  111
   Current serial number in output stream:  111


Do you have any hint about this? Should I try the RC 7.1 or switch to 
the plain OpenGL back-end ?

Thanks in advance for any suggestion,

Best Regards,

Andrea