var rot_changeables_images = new Array();
var rot_current_item = null;

function changeItem( ) {
	
	if( rot_current_item == null ) {
		rot_current_item = new Array();
		for( var i=0; i<rot_changeables_images.length; i++ ) {
			rot_current_item.push( 0 );
		}
	}
	
	for( var i=0; i<rot_changeables_images.length; i++ ) {
		
		img = document.getElementById( 'rot_img_image_' + i );
		img.src = rot_changeables_images[i][rot_current_item[i]];
		if( ++rot_current_item[i] >= rot_changeables_images[i].length ) rot_current_item[i] = 0;
	}
}