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diff --git a/src/static/js/colorutils.js b/src/static/js/colorutils.js
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+/**
+ * This code is mostly from the old Etherpad. Please help us to comment this code. 
+ * This helps other people to understand this code better and helps them to improve it.
+ * TL;DR COMMENTS ON THIS FILE ARE HIGHLY APPRECIATED
+ */
+
+// DO NOT EDIT THIS FILE, edit infrastructure/ace/www/colorutils.js
+// THIS FILE IS ALSO SERVED AS CLIENT-SIDE JS
+/**
+ * Copyright 2009 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+var colorutils = {};
+
+// "#ffffff" or "#fff" or "ffffff" or "fff" to [1.0, 1.0, 1.0]
+colorutils.css2triple = function(cssColor)
+{
+  var sixHex = colorutils.css2sixhex(cssColor);
+
+  function hexToFloat(hh)
+  {
+    return Number("0x" + hh) / 255;
+  }
+  return [hexToFloat(sixHex.substr(0, 2)), hexToFloat(sixHex.substr(2, 2)), hexToFloat(sixHex.substr(4, 2))];
+}
+
+// "#ffffff" or "#fff" or "ffffff" or "fff" to "ffffff"
+colorutils.css2sixhex = function(cssColor)
+{
+  var h = /[0-9a-fA-F]+/.exec(cssColor)[0];
+  if (h.length != 6)
+  {
+    var a = h.charAt(0);
+    var b = h.charAt(1);
+    var c = h.charAt(2);
+    h = a + a + b + b + c + c;
+  }
+  return h;
+}
+
+// [1.0, 1.0, 1.0] -> "#ffffff"
+colorutils.triple2css = function(triple)
+{
+  function floatToHex(n)
+  {
+    var n2 = colorutils.clamp(Math.round(n * 255), 0, 255);
+    return ("0" + n2.toString(16)).slice(-2);
+  }
+  return "#" + floatToHex(triple[0]) + floatToHex(triple[1]) + floatToHex(triple[2]);
+}
+
+
+colorutils.clamp = function(v, bot, top)
+{
+  return v < bot ? bot : (v > top ? top : v);
+};
+colorutils.min3 = function(a, b, c)
+{
+  return (a < b) ? (a < c ? a : c) : (b < c ? b : c);
+};
+colorutils.max3 = function(a, b, c)
+{
+  return (a > b) ? (a > c ? a : c) : (b > c ? b : c);
+};
+colorutils.colorMin = function(c)
+{
+  return colorutils.min3(c[0], c[1], c[2]);
+};
+colorutils.colorMax = function(c)
+{
+  return colorutils.max3(c[0], c[1], c[2]);
+};
+colorutils.scale = function(v, bot, top)
+{
+  return colorutils.clamp(bot + v * (top - bot), 0, 1);
+};
+colorutils.unscale = function(v, bot, top)
+{
+  return colorutils.clamp((v - bot) / (top - bot), 0, 1);
+};
+
+colorutils.scaleColor = function(c, bot, top)
+{
+  return [colorutils.scale(c[0], bot, top), colorutils.scale(c[1], bot, top), colorutils.scale(c[2], bot, top)];
+}
+
+colorutils.unscaleColor = function(c, bot, top)
+{
+  return [colorutils.unscale(c[0], bot, top), colorutils.unscale(c[1], bot, top), colorutils.unscale(c[2], bot, top)];
+}
+
+colorutils.luminosity = function(c)
+{
+  // rule of thumb for RGB brightness; 1.0 is white
+  return c[0] * 0.30 + c[1] * 0.59 + c[2] * 0.11;
+}
+
+colorutils.saturate = function(c)
+{
+  var min = colorutils.colorMin(c);
+  var max = colorutils.colorMax(c);
+  if (max - min <= 0) return [1.0, 1.0, 1.0];
+  return colorutils.unscaleColor(c, min, max);
+}
+
+colorutils.blend = function(c1, c2, t)
+{
+  return [colorutils.scale(t, c1[0], c2[0]), colorutils.scale(t, c1[1], c2[1]), colorutils.scale(t, c1[2], c2[2])];
+}
+
+colorutils.invert = function(c)
+{
+  return [1 - c[0], 1 - c[1], 1- c[2]];
+}
+
+colorutils.complementary = function(c)
+{
+  var inv = colorutils.invert(c);
+  return [
+    (inv[0] >= c[0]) ? Math.min(inv[0] * 1.30, 1) : (c[0] * 0.30),
+    (inv[1] >= c[1]) ? Math.min(inv[1] * 1.59, 1) : (c[1] * 0.59),
+    (inv[2] >= c[2]) ? Math.min(inv[2] * 1.11, 1) : (c[2] * 0.11)
+  ];
+}
+
+exports.colorutils = colorutils;