/* This script and many more are available free online at
The JavaScript Source!! http://javascript.internet.com
Created by: Jay M. Rumsey, OD | http://www.nova.edu/~rumsey */

var num=0;

imgArray = [
  ['visual_illusions/classic_optical_illusions_1.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_2.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_3.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_4.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_5.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_6.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_7.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_8.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_9.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_10.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_11.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_12.jpg','', ''],
  ['visual_illusions/classic_optical_illusions_1.jpg','', '']
 
]

function slideshow(slide_num) {
  document.getElementById('mypic').src=imgArray[slide_num][0];
  document.getElementById('mypic').alt=imgArray[slide_num][1];
  document.getElementById('burns').innerHTML=imgArray[slide_num][2];
}

function slideshowUp() {
  num++;
  num = num % imgArray.length;
  slideshow(num);
}

function slideshowBack() {
  num--;
  if (num < 0) {num=imgArray.length-1;}
  num = num % imgArray.length;
  slideshow(num);
}