My OpenGL skill is poor, can only do some simple polygon drawings and animations. I have to start learning OpenGL Core Profile or soon I will be left behind.
Thank ChrisR for the information.
That surprises me, GTK3 has been developed for quite long time but has such limitations. Any info about GTK4? I heard current stable version is 4.0.3. Do you think maybe we should ignore GTK3 but go directly to the version 4?