| /** |
| * Copyright 2013 Google Inc. All Rights Reserved. |
| * |
| * 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. |
| */ |
| |
| (function(){ |
| 'use strict'; |
| |
| var disregardFramesCount = 10; |
| var framesPerTimeReading = 10; |
| var maxTimeReadings = 60; |
| var maxFPSReadings = 31; |
| |
| var frameCount = 0; |
| var timeReadings = []; |
| var fpsReadings = []; |
| var onCompleteHandler; |
| var outputElement; |
| var running = false; |
| var visibilityLost = false; |
| |
| var getTime = (typeof window.performance === 'object' && |
| typeof window.performance.now === 'function') ? |
| function() { return window.performance.now(); } : |
| function() { return Date.now(); }; |
| |
| var raf = window.requestAnimationFrame || |
| window.webkitRequestAnimationFrame || |
| window.mozRequestAnimationFrame || |
| function(callback) { setTimeout(callback, 1000 / 60); }; |
| |
| var visibilityChangeEvent = null; |
| var hidden = null; |
| if (typeof document.hidden !== 'undefined') { |
| visibilityChangeEvent = 'visibilitychange'; |
| hidden = 'hidden'; |
| } else if (typeof document.mozHidden !== 'undefined') { |
| visibilityChangeEvent = 'mozvisibilitychange'; |
| hidden = 'mozHidden'; |
| } else if (typeof document.msHidden !== 'undefined') { |
| visibilityChangeEvent = 'msvisibilitychange'; |
| hidden = 'msHidden'; |
| } else if (typeof document.webkitHidden !== 'undefined') { |
| visibilityChangeEvent = 'webkitvisibilitychange'; |
| hidden = 'webkitHidden'; |
| } |
| if (visibilityChangeEvent) { |
| document.addEventListener(visibilityChangeEvent, function() { |
| if (running && document[hidden]) { |
| visibilityLost = true; |
| } |
| }); |
| } |
| |
| var randomSeed = 3384413; |
| function random() { |
| var temp = randomSeed; |
| // Robert Jenkins' 32 bit integer hash function. |
| temp = ((temp + 0x7ed55d16) + (temp << 12)) & 0xffffffff; |
| temp = ((temp ^ 0xc761c23c) ^ (temp >>> 19)) & 0xffffffff; |
| temp = ((temp + 0x165667b1) + (temp << 5)) & 0xffffffff; |
| temp = ((temp + 0xd3a2646c) ^ (temp << 9)) & 0xffffffff; |
| temp = ((temp + 0xfd7046c5) + (temp << 3)) & 0xffffffff; |
| temp = ((temp ^ 0xb55a4f09) ^ (temp >>> 16)) & 0xffffffff; |
| randomSeed = temp; |
| return (randomSeed & 0xfffffff) / 0x10000000; |
| } |
| |
| function disregardFrames() { |
| raf((frameCount++ < disregardFramesCount) ? disregardFrames : trackFrameRate); |
| } |
| |
| function trackFrameRate() |
| { |
| frameCount++; |
| if (frameCount % framesPerTimeReading === 0) { |
| timeReadings.unshift(getTime()); |
| if (timeReadings.length > maxTimeReadings) { |
| timeReadings.pop(); |
| } |
| if (timeReadings.length > 1) { |
| var fpsReading = 1000 * (timeReadings.length - 1) * framesPerTimeReading / |
| (timeReadings[0] - timeReadings[timeReadings.length - 1]); |
| fpsReadings.push(fpsReading); |
| output(fpsReading + ' FPS\n'); |
| if (fpsReadings.length >= maxFPSReadings) { |
| outputSummary(); |
| running = false; |
| if (typeof onCompleteHandler === 'function') { |
| onCompleteHandler(); |
| } |
| return; |
| } |
| } |
| } |
| raf(trackFrameRate); |
| } |
| |
| function output(text) { |
| outputElement.value += text; |
| } |
| |
| function outputSummary() { |
| if (visibilityLost) { |
| output('Warning: Document lost visibility during test, ' + |
| 'results may be inaccurate.\n'); |
| } |
| var total = 0; |
| fpsReadings.forEach(function(fpsReading) { total += fpsReading; }); |
| var average = total / maxFPSReadings; |
| output('Average: ' + average + ' FPS\n'); |
| var temp = 0; |
| fpsReadings.forEach(function(fpsReading) { |
| temp += (fpsReading - average) * (fpsReading - average); |
| }); |
| output('Stddev: ' + Math.sqrt(temp / fpsReadings.length) + ' FPS\n'); |
| fpsReadings.sort(); |
| output('Min: ' + fpsReadings[0] + ' FPS\n'); |
| output('Max: ' + fpsReadings[fpsReadings.length - 1] + ' FPS\n'); |
| var median = fpsReadings[fpsReadings.length >> 1]; |
| if (fpsReadings.length % 2 !== 0) { |
| median = (median + fpsReadings[(fpsReadings.length >> 1) + 1]) / 2; |
| } |
| output('Median: ' + median + ' FPS\n'); |
| } |
| |
| var start = function() { |
| outputElement = document.createElement('textarea'); |
| outputElement.setAttribute('rows', maxFPSReadings + 6); |
| outputElement.setAttribute('cols', 32); |
| document.body.appendChild(outputElement); |
| |
| output('Disregarding initial ' + disregardFramesCount + ' frames.\n') |
| raf(disregardFrames); |
| |
| running = true; |
| }; |
| |
| window.Perf = { |
| set oncomplete(callback) { |
| onCompleteHandler = callback; |
| }, |
| start: start, |
| random: random, |
| }; |
| |
| })(); |