the #GtkWidget to be used as the rendering area.
a #GdkGLConfig.
the #GdkGLContext with which to share display lists and texture objects. NULL indicates that no sharing is to take place.
whether rendering is to be done with a direct connection to the graphics system.
GDK_GL_RGBA_TYPE.
Return: TRUE if it is successful, FALSE otherwise.
Set the OpenGL-capability to the @widget. This function prepares the widget for its use with OpenGL.