TYPEMAP
UIContext *   O_X11_MinimalOpenGLViewport_UIContext

OUTPUT
O_X11_MinimalOpenGLViewport_UIContext
    sv_setref_pv( $arg, "X11::MinimalOpenGLViewport::UIContext", (void*)$var );

INPUT
O_X11_MinimalOpenGLViewport_UIContext
    if (sv_isobject($arg) && (SvTYPE(SvRV($arg)) == SVt_PVMG)) {
        $var = ($type)SvIV((SV*)SvRV( $arg ));
    }
    else {
        croak ( \"${Package}::$func_name() -- $var is not a blessed reference\" );
    }
