pdr0 = new Image; pdr0.src = 'images/pdr0.gif';
pdr1 = new Image; pdr1.src = 'images/pdr1.gif';
pdr2 = new Image; pdr2.src = 'images/pdr2.gif';
pdr3 = new Image; pdr3.src = 'images/pdr3.gif';