Thanks, Paul so much, really appreciate your fast reply!

I returned one step back and avoided the use of NoMachine (i.e, I hooked a screen to the Linux machine directly). I got a different error when I run Fsleyes:

[meena@ghine ~]$  WARNING          __init__.py  596: create          - GLContext callback function raised NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling
Traceback (most recent call last):
  File "fsleyes/gl/__init__.py", line 590, in create
  File "fsleyes/main.py", line 371, in realCallback
  File "fsleyes/gl/__init__.py", line 377, in bootstrap
  File "site-packages/OpenGL/GLUT/special.py", line 333, in glutInit
  File "site-packages/OpenGL/platform/baseplatform.py", line 407, in __call__
NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling

As the Fsleyes troubleshooting page suggested, I need to install glutInit. I followed the recommended link (http://freeglut.sourceforge.net/docs/install.php) and I followed the steps:
1- zcat freeglut-2.2.0.tar.bz2 | tar -vxf -
2- cd freeglut-2.X.X
3- LDFLAGS=-Wl,-R/usr/X11R6/lib ./configure
4- make all
5- make install

Steps (1-3) was done without errors. However, in step 4 (make all), it gave me this error:

make  all-recursive
make[1]: Entering directory `/home/meena/freeglut-2.8.0'
Making all in src
make[2]: Entering directory `/home/meena/freeglut-2.8.0/src'
/bin/sh ../libtool  --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I. -I..  -I../include     -g -O2 -Wall -pedantic -MT libglut_la-freeglut_callbacks.lo -MD -MP -MF .deps/libglut_la-freeglut_callbacks.Tpo -c -o libglut_la-freeglut_callbacks.lo `test -f 'freeglut_callbacks.c' || echo './'`freeglut_callbacks.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I.. -I../include -g -O2 -Wall -pedantic -MT libglut_la-freeglut_callbacks.lo -MD -MP -MF .deps/libglut_la-freeglut_callbacks.Tpo -c freeglut_callbacks.c  -fPIC -DPIC -o .libs/libglut_la-freeglut_callbacks.o
In file included from ../include/GL/freeglut.h:17,
                 from freeglut_callbacks.c:28:
../include/GL/freeglut_std.h:123:20: error: GL/glu.h: No such file or directory
In file included from freeglut_callbacks.c:29:
freeglut_internal.h:112:39: error: X11/extensions/XInput.h: No such file or directory
make[2]: *** [libglut_la-freeglut_callbacks.lo] Error 1
make[2]: Leaving directory `/home/meena/freeglut-2.8.0/src'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/meena/freeglut-2.8.0'
make: *** [all] Error 2

I did these steps as a superuser as recommended and I tried different versions of the glutInit and all gave the same error message.

Unfortunately, I did not find any help online. Any direction I can try?

Thanks again Paul;
--Meena

On Sat, Mar 24, 2018 at 6:29 AM, paul mccarthy <[log in to unmask]> wrote:
Hi Meena,

You could try running FSLeyes with the LIBGL_ALWAYS_SOFTWARE environment variable, e.g.:

LIBGL_ALWAYS_SOFTWARE=1 fsleyes 

If FSLeyes works in this way, and is fast enough, then you can use this as a solution.

Alternately, one person has reported success in getting around this problem by following the steps described here:


I have translated the Ubuntu 14.04 instructions to their CentOS 6.9 equivalents here:


Let me know how you get on.

Cheers,

Paul

On 23 March 2018 at 21:09, Meena M. Makary <[log in to unmask]> wrote:
Dear FSL experts;

I am trying to run FSLeyes from "NoMachine” on Centos 6.9 and it gives me the following error:

WARNING          __init__.py  596: create          - GLContext callback function raised RuntimeError: OpenGL 1.4 or newer is required (detected version: 1.2
Traceback (most recent call last):
  File "fsleyes/gl/__init__.py", line 590, in create
  File "fsleyes/main.py", line 371, in realCallback
  File "fsleyes/gl/__init__.py", line 315, in bootstrap
RuntimeError: OpenGL 1.4 or newer is required (detected version: 1.2

I tried “unset LIBGL_ALWAYS_INDIRECT “, as recommended on the troubleshooting page (https://users.fmrib.ox.ac.uk/~paulmc/fsleyes/userdoc/latest/troubleshooting.html), and still gives me the same error.

Any help would be much appreciated!

Thanks,

-- 
Meena M. Makary, Ph.D.
Assistant Professor | Cairo University 
Postdoctoral Fellow | Yale University School of Medicine
Postdoctoral Associate |  The John B. Pierce Laboratory





--

Meena M. Makary, Ph.D.
Assistant Professor | Cairo University 
Postdoctoral Fellow | Yale University School of Medicine
Postdoctoral Associate |  The John B. Pierce Laboratory
Executive Committee Member | OHBM Student and Postdoc SIG

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