Re: [Discuss-gnuradio] plotter_base.py problem

[Marcus D. Leech]

On 07/17/2011 08:47 PM, Miguel A. Vallejo, EA4EOZ wrote:
> Hello!
>
> I'm trying to play a bit with gnuradio and a funcube dongle pro but 
> I'm having problems making gnuradio work. I'm using a fresh ubuntu 
> 11.04 install and gnuradio 3.4.0 built from sources.
>
> Everytime a fft display is used, I get the same error. For example, 
> using FunCube Dongle Pro example:
>
>
>
> address@hidden:~$ FCDongle/gr-fcd/apps/fcd_fft_wx.py
> Traceback (most recent call last):
>   File 
> "/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/plotter/plotter_base.py", 
> line 158, in _on_paint
>     GL.glClearColor(*BACKGROUND_COLOR_SPEC)
>   File "/usr/lib/pymodules/python2.7/OpenGL/error.py", line 208, in 
> glCheckError
>     baseOperation = baseOperation,
> OpenGL.error.GLError: GLError(
>     err = 1280,
>     baseOperation = glClearColor,
>     cArguments = (1, 0.976, 1, 1)
> )
>
>
> And testing this little GUI example from 
> http://www.funwithelectronics.com/?id=10
>
>
> address@hidden:~./simplegui.py
> Traceback (most recent call last):
>   File 
> "/usr/local/lib/python2.7/dist-packages/gnuradio/wxgui/plotter/plotter_base.py", 
> line 158, in _on_paint
>     GL.glClearColor(*BACKGROUND_COLOR_SPEC)
>   File "/usr/lib/pymodules/python2.7/OpenGL/error.py", line 208, in 
> glCheckError
>     baseOperation = baseOperation,
> OpenGL.error.GLError: GLError(
>     err = 1280,
>     baseOperation = glClearColor,
>     cArguments = (1, 0.976, 1, 1)
> )
Just on a hunch, try:

export LIBGL_ALWAYS_INDIRECT=1

Before you start any of the above applications.

OpenGL has, in my opinion, become a festering sore of incompatibilities 
and weird edge conditions.  It used to work reliably on just about
  anything, but not anymore.  Newer version of OpenGL require various 
extensions in your display hardware, and will fail in weird ways
  if your display hardware doesn't have what it expects.  The above 
environment variable is supposed to instruct OpenGL to use software-based
  rendering and ignore the hardware.  For the simple 2-D stuff we do in 
Gnu Radio, Software-Based rendering is just fine.



--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org