QOpenGLShaderProgram::hasOpenGLShaderPrograms tests whether
QOpenGLFunctions::Shaders is provided for the given context. As the
initialization code assumed OpenGL 2 this always was true. But
unfortunately we still cannot assume that OpenGL 2 is universally
supported. E.g. indirect rendering (no matter how bad that idea is)
does not support OpenGL 2 on all hardware and the Shader related
extensions are not available.
This change makes sure that only when OpenGL 2 is available the
features provided by OpenGL 2 are enabled. If OpenGL 2 is not
available the extensions are tested. The checks are slightly
reordered to not do the extension tests at all if OpenGL 2 is
available.
Task-number: QTBUG-39730
Change-Id: Ic775163e0dcc519925b1287f3c4ca5e8ebf101d5
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
473ed1c1aa