(function(window, document, undefined){
  window.onload = init;
  function init(){
    var c = document.getElementById("mapCanvas");
    var ctx = c.getContext("2d");
    var id = ctx.createImageData(1,1);
    var d = id.data;
    d[0] = r;
    d[1] = g;
    d[2] = b;
    d[3] = a;
    for(x=0; x<50; x++){
      for(y=0; y<50; y++){
        ctx.putImageData(id, x, y);
      }
    }
})(window, document, undefined);

@@ -231,17 +231,19 @@
  d%5B0%5D = 
-r
+255
 ;%0A    d%5B
@@ -247,17 +247,19 @@
  d%5B1%5D = 
-g
+255
 ;%0A    d%5B
@@ -267,9 +267,11 @@
 %5D = 
-b
+255
 ;%0A  
@@ -279,17 +279,19 @@
  d%5B3%5D = 
-a
+255
 ;%0A    fo

Update script.js