Check the value of your lighting variable on the other computer.ok, checked
Usually, the value of the lighting-variable should be 2 nearly all the time;
but to be certain, I changed the code of the shaders to make them do always the same, regardless of the value of this variable.
When we tested it on the problematic computers, no differences was to be found...
Also, I tested it the other way round, now on my computer:
I set the shaders to only act like lighting was 1 all the time. No great differences, just slightly darker and no directional light.
So the lighting variable should act like it is supposed to act, thanks for the suggestion anyway.
I think there may be some calculation of some vector or something that is done differently on both computers.
To eliminate as many sources for errors as possible, I checked the version of OpenGL on the computers.
We both use the same version, 4.2.