Introduce non auto-scaling mode in spinning balls benchmark.

benchmarks/spinning-balls/v.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 43 matching lines @@
 var dyingPoints = void 0;
 var scene = void 0;
 var renderingStartTime = void 0;
 var scene = void 0;
 var pausePlot = void 0;
 var splayTree = void 0;
 var numberOfFrames = 0;
 var sumOfSquaredPauses = 0;
 var benchmarkStartTime = void 0;
 var benchmarkTimeLimit = void 0;
+var autoScale = void 0;
 var pauseDistribution = [];
 
 
 function Point(x, y, z, payload) {
   this.x = x;
   this.y = y;
   this.z = z;
 
   this.next = null;
   this.prev = null;
@@ skipping 112 matching lines @@
     } else {
       var point = splayTree.remove(greatest.key).value;
     }
     livePoints.remove(point);
     point.payload = null;
     dyingPoints.add(point);
   }
 }
 
 
-function PausePlot(width, height, size) {
+function PausePlot(width, height, size, scale) {
   var canvas = document.createElement("canvas");
   canvas.width = this.width = width;
   canvas.height = this.height = height;
   document.body.appendChild(canvas);
 
   this.ctx = canvas.getContext('2d');
 
-  this.maxPause = 0;
+  if (typeof scale !== "number") {
+    this.autoScale = true;
+    this.maxPause = 0;
+  } else {
+    this.autoScale = false;
+    this.maxPause = scale;
+  }
+
   this.size = size;
 
   // Initialize cyclic buffer for pauses.
   this.pauses = new Array(this.size);
   this.start = this.size;
   this.idx = 0;
 }
 
 
 PausePlot.prototype.addPause = function (p) {
@@ skipping 26 matching lines @@
     var offs = this.size - this.start;
     for (var i = 0; i < this.idx; i++) {
       f.call(this, i + offs, this.pauses[i]);
     }
   }
 };
 
 
 PausePlot.prototype.draw = function () {
   var first = null;
-  this.iteratePauses(function (i, v) {
-    if (first === null) {
-      first = v;
-    }
-    this.maxPause = Math.max(v, this.maxPause);
-  });
+
+  if (this.autoScale) {
+    this.iteratePauses(function (i, v) {
+      if (first === null) {
+        first = v;
+      }
+      this.maxPause = Math.max(v, this.maxPause);
+    });
+  }
 
   var dx = this.width / this.size;
   var dy = this.height / this.maxPause;
 
   this.ctx.save();
-  this.ctx.clearRect(0, 0, 480, 240);
+  this.ctx.clearRect(0, 0, this.width, this.height);
   this.ctx.beginPath();
   this.ctx.moveTo(1, dy * this.pauses[this.start]);
   var p = first;
   this.iteratePauses(function (i, v) {
     var delta = v - p;
     var x = 1 + dx * i;
     var y = dy * v;
     this.ctx.lineTo(x, y);
     if (delta > 2 * (p / 3)) {
       this.ctx.font = "bold 12px sans-serif";
@@ skipping 134 matching lines @@
 
   if (renderingEndTime < benchmarkStartTime + benchmarkTimeLimit) {
     // Schedule next frame.
     requestAnimationFrame(render);
   } else {
     renderStats();
   }
 }
 
 
-function renderForm() {
-  form = document.createElement("form");
-  form.setAttribute("action", "javascript:start()");
-  var label = document.createTextNode("Time limit in seconds ");
-  var input = document.createElement("input");
-  input.setAttribute("id", "timelimit");
-  input.setAttribute("value", "60");
-  var button = document.createElement("input");
+function Form() {
+  function create(tag) { return document.createElement(tag); }
+  function text(value) { return document.createTextNode(value); }
+  
+  this.form = create("form");
+  this.form.setAttribute("action", "javascript:start()");
+
+  var table = create("table");
+  table.setAttribute("style", "margin-left: auto; margin-right: auto;");
+
+  function col(a) {
+    var td = create("td");
+    td.appendChild(a);
+    return td;
+  }
+
+  function row(a, b) {
+    var tr = create("tr");
+    tr.appendChild(col(a));
+    tr.appendChild(col(b));
+    return tr; 
+  }
+
+  this.timelimit = create("input");
+  this.timelimit.setAttribute("value", "60");
+
+  table.appendChild(row(text("Time limit in seconds"), this.timelimit));
+
+  this.autoscale = create("input");
+  this.autoscale.setAttribute("type", "checkbox");
+  this.autoscale.setAttribute("checked", "true");
+  table.appendChild(row(text("Autoscale pauses plot"), this.autoscale));
+
+  var button = create("input");
   button.setAttribute("type", "submit");
   button.setAttribute("value", "Start");
-  form.appendChild(label);
-  form.appendChild(input);
-  form.appendChild(button);
-  document.body.appendChild(form);
+  this.form.appendChild(table);
+  this.form.appendChild(button);
+
+  document.body.appendChild(this.form);
 }
 
 
+Form.prototype.remove = function () {
+  document.body.removeChild(this.form);
+};
+
+
 function init() {
   livePoints = new PointsList;
   dyingPoints = new PointsList;
 
   splayTree = new SplayTree();
 
   scene = new Scene(640, 480);
 
   div = document.createElement("div");
   document.body.appendChild(div);
 
-  pausePlot = new PausePlot(480, 240, 160);
+  pausePlot = new PausePlot(480, autoScale ? 240 : 500, 160, autoScale ? void 0 : 500);
 }
 
 function start() {
-  benchmarkTimeLimit = document.getElementById("timelimit").value * 1000;
-  document.body.removeChild(form);
+  benchmarkTimeLimit = form.timelimit.value * 1000;
+  autoScale = form.autoscale.checked;
+  form.remove();
   init();
   render();
 }
 
-renderForm();
+var form = new Form();