currentpicture := currentpicture shifted -(width / 2, height / 2);
currentpicture := currentpicture rotated 90;
currentpicture := currentpicture shifted (height / 2, width / 2);
currentpicture := currentpicture shifted -(width / 2, height / 2);
currentpicture := currentpicture rotated 90;
currentpicture := currentpicture shifted (height / 2, width / 2);