gistfile1.txt

GtkOffscreenWindow* offscreenWindow;

GtkPixmap* snapshotWidget(GtkWidget* widget) {
	// Caching doesn't work, must create a new one every time (the widget parameter is gtk_widget_destroy'ed by the caller)
	// if (!offscreenWindow)
		offscreenWindow = gtk_offscreen_window_new();

	gtk_container_add(offscreenWindow, widget);
	gtk_widget_show(offscreenWindow);
	force_draw(widget);

        // This doesn't seem to make any difference
        // force_draw(offscreenWindow);

        GtkPixmap* result = gtk_offscreen_window_get_pixmap(offscreenWindow)

	// Doesn't work
	// gtk_widget_destroy(offscreenWindow);

	return result;
}

void force_draw(GtkWidget* widget) {
    gtk_widget_queue_draw(widget);

    GdkWindow* window = gtk_widget_get_window(widget);

    gdk_window_process_updates(window, true);
}