void histo_drawing_update_vertical_ruler(histoDrawing_t *drawing);//, TimeWindow *time_window);
void histo_drawing_request_expose(EventsRequest *events_request,
void histo_drawing_update_vertical_ruler(histoDrawing_t *drawing);//, TimeWindow *time_window);
void histo_drawing_request_expose(EventsRequest *events_request,