How can I randomize images without repeat in a highslide gallery?

Question

So far I've done an amazing job at integrating randomization with my highslide gallery. But now I'm trying to make it so that they don't repeat. Any suggestions? I've looked at several other posts, but can't seem to apply it to my code correctly. I'm still learning; you'll have to forgive me.

Here's my head code (javascript):

var gallery = new Array();
gallery[0] = new Array("earlywork001.jpg","earlywork002.jpg","earlywork003.jpg");

function pickImageFrom(whichGallery)
{
var idx = Math.floor(Math.random() * gallery[whichGallery].length);
document.write('<a href="images/earlywork/' + gallery[whichGallery][idx] + '" class="highslide" onclick="return hs.expand(this, config1 )"><img src="images/earlywork/' + gallery[whichGallery][idx] + '" width="140" height="140"></a>');
}

Here's my body code (I only put 3 to make it simple, but I actually have 50 images):

<div class="highslide-gallery"><script language="javascript">pickImageFrom(0);</script>
    <span class="highslide-heading"><i>Copyright © 2012 KD Neeley</i></span></div>

<div class="highslide-gallery"><script language="javascript">pickImageFrom(0);</script>
    <span class="highslide-heading"><i>Copyright © 2012 KD Neeley</i></span></div>

<div class="highslide-gallery"><script language="javascript">pickImageFrom(0);</script>
    <span class="highslide-heading"><i>Copyright © 2012 KD Neeley</i></span></div>

Answer 1

You could add all images to a js array. Make a function that gets an img from the array. Use the function to decide which image to show.

var images = ["img1.jpg","img2.jpg"];
var shownImages = [];

function randomimg(images,shownImages){

   //select a random number from with in the range of the image array
   rand = Math.floor((Math.random()*images.length())+1);
   //store the displayed image in the shown array and remove it from images
   shownImages.unshift(images.splice(rand,rand+1));

   //if the image array is empty 
   //I guess we would like to show the images over again so resetit
   //The commented out part is only necessary if you want to show
   //images in a loop
   /*if(images.length == 0){
     images = shownImages;
     shownImages = [];
   }*/

   //return the image to show this time.
   return shownImages[0];
}

Answer 2

Add shuffle to array prototype

Array.prototype.shuffle=function(){
   var i = len = this.length;       
   while (i--) {
      var r = Math.round(Math.random(len));
      var t = this[i];
      this[i] = this[r];
      this[r] = t;
   }
   return this;
}

And then you can use the shuffle method with any array:

gallery.shuffle(); // this shuffles the array

demo: http://jsfiddle.net/W75Kw/1/

Update as requested: Using your posted code:

var gallery = new Array();
gallery[0] = new Array("earlywork001.jpg","earlywork002.jpg","earlywork003.jpg");
gallery[0].shuffle(); // randomize array

function pickImageFrom(whichGallery) {
  var img = gallery[whichGallery].pop(); // extracts element from array
  document.write('<a href="images/earlywork/' + img + '" class="highslide" onclick="return hs.expand(this, config1 )"><img src="images/earlywork/' + img + '" width="140" height="140"></a>');
}