/**
 *  functions to replace link images
 */

/**
 *  array that contains the images
 */
replace_images = new Array();
replace_image_count = 0;

/**
 *  loads a set of images
 *
 *  @param string image_name   name of the image
 *  @param string url_1        first image url
 *  @param string url_2        second image url
 *  @param string url_3        third image url (not required)
 */
function replace_load_image(image_name, url_1, url_2, url_3)
{
  replace_images[replace_image_count] = new Array(4);
  replace_images[replace_image_count][0] = image_name; 
  replace_images[replace_image_count][1] = new Image();
  replace_images[replace_image_count][1].src = url_1;
  replace_images[replace_image_count][2] = new Image();
  replace_images[replace_image_count][2].src = url_2;
  replace_images[replace_image_count][3] = new Image();
  replace_images[replace_image_count][3].src = url_3;
  replace_image_count++;
}

/**
 *  switches the image with the given name
 *
 *  @param string name   name of the image to light
 *  @param int    image  id of the image:
 *                       - 1 - image 1
 *                       - 2 - image 2
 *                       - 3 - image 3
 */
function replace_switch_image(name, image)
{
	var i, a;

	//  search the image to replace
	for (a=0; a<replace_image_count; a++)
	{
	  if (replace_images[a][0] == name)
		{
	    //  search the image in the document
      for(i=0; i<document.images.length; i++)
      {
	      if (document.images[i].name == name) document.images[i].src = replace_images[a][image].src;
      }		
		}
	}	
}