Removed old timesteps and renamed Variable to TimeStep.

Author: photonstorm

v3/src/boot/Game.js

@@ -1,8 +1,3 @@
-/**
-* @author       Richard Davey <rich@photonstorm.com>
-* @copyright    2016 Photon Storm Ltd.
-* @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
-*/
 
 var Config = require('./Config');
 var DebugHeader = require('./DebugHeader');
@@ -11,9 +6,7 @@ var Device = require('../device');
 var AddToDOM = require('../dom/AddToDOM');
 var DOMContentLoaded = require('../dom/DOMContentLoaded');
 
-var MainLoop = require('./MainLoop');
-var TickerLoop = require('./TickerLoop');
-var VariableTimeStep = require('./VariableTimeStep');
+var TimeStep = require('./TimeStep');
 var CreateRenderer = require('./CreateRenderer');
 var GlobalInputManager = require('../input/GlobalInputManager');
 var GlobalStateManager = require('../state/GlobalStateManager');
@@ -72,14 +65,7 @@ var Game = function (config)
     * @property {Phaser.MainLoop} mainloop - Main Loop handler.
     * @protected
     */
-    // if (this.config.useTicker)
-    // {
-        this.loop = new VariableTimeStep(this, this.config.fps);
-    // }
-    // else
-    // {
-    //     this.loop = new MainLoop(this, this.config.fps);
-    // }
+    this.loop = new TimeStep(this, this.config.fps);
 
     //  Wait for the DOM Ready event, then call boot.
     DOMContentLoaded(this.boot.bind(this));

v3/src/boot/MainLoop.js

@@ -1,7 +1,7 @@
 var NOOP = require('../utils/NOOP');
 var RequestAnimationFrame = require('../dom/RequestAnimationFrame');
 
-var TickerLoop = function (game, framerate)
+var Ticker = function (game, framerate)
 {
     this.game = game;
 
@@ -29,9 +29,9 @@ var TickerLoop = function (game, framerate)
     this.useRAF = true;
 };
 
-TickerLoop.prototype.constructor = TickerLoop;
+Ticker.prototype.constructor = Ticker;
 
-TickerLoop.prototype = {
+Ticker.prototype = {
 
     toString: function ()
     {
@@ -157,4 +157,4 @@ TickerLoop.prototype = {
 
 };
 
-module.exports = TickerLoop;
+module.exports = Ticker;

v3/src/boot/TickerLoop.js v3/src/boot/Ticker.jsv3/src/boot/TickerLoop.js renamed to v3/src/boot/Ticker.js

@@ -11,7 +11,7 @@ var RequestAnimationFrame = require('../dom/RequestAnimationFrame');
 //          deltaHistory: 10
 //     }
 
-var VariableTimeStep = function (game, config)
+var TimeStep = function (game, config)
 {
     this.game = game;
 
@@ -32,6 +32,15 @@ var VariableTimeStep = function (game, config)
     //  8.333 / 1000 = 0.008333 (120fps)
     //  16.666 / 1000 = 0.01666 (60fps)
 
+    /**
+    * @property {number} fps - An exponential moving average of the frames per second.
+    * @readOnly
+    */
+    this.actualFps = this.targetFps;
+
+    this.nextFpsUpdate = 0;
+    this.framesThisSecond = 0;
+
     this.callback = NOOP;
 
     this.forceSetTimeOut = GetValue(config, 'forceSetTimeOut', false);
@@ -46,9 +55,9 @@ var VariableTimeStep = function (game, config)
     this.deltaSmoothingMax = GetValue(config, 'deltaHistory', 10);
 };
 
-VariableTimeStep.prototype.constructor = VariableTimeStep;
+TimeStep.prototype.constructor = TimeStep;
 
-VariableTimeStep.prototype = {
+TimeStep.prototype = {
 
     start: function (callback)
     {
@@ -65,7 +74,8 @@ VariableTimeStep.prototype = {
         this.time = now;
         this.startTime = now;
         this.lastTime = now;
-        this.runOff = 0;
+        this.nextFpsUpdate = now + 1000;
+        this.framesThisSecond = 0;
 
         //  Pre-populate smoothing array
 
@@ -137,7 +147,26 @@ VariableTimeStep.prototype = {
         //  Real-world timer advance
         this.time += avg;
 
-        this.callback(this.time, avg);
+        // Update the estimate of the frame rate, `fps`. Every second, the number
+        // of frames that occurred in that second are included in an exponential
+        // moving average of all frames per second, with an alpha of 0.25. This
+        // means that more recent seconds affect the estimated frame rate more than
+        // older seconds.
+        if (time > this.nextFpsUpdate)
+        {
+            // Compute the new exponential moving average with an alpha of 0.25.
+            // Using constants inline is okay here.
+            this.actualFps = 0.25 * this.framesThisSecond + 0.75 * this.actualFps;
+            this.nextFpsUpdate = time + 1000;
+            this.framesThisSecond = 0;
+        }
+
+        this.framesThisSecond++;
+
+        //  Interpolation - how far between what is expected and where we are?
+        var interpolation = avg / this._target;
+
+        this.callback(this.time, avg, interpolation);
 
         //  Shift time value over
         this.lastTime = time;
@@ -197,7 +226,6 @@ VariableTimeStep.prototype = {
 
         return this;
     }
-
 };
 
-module.exports = VariableTimeStep;
+module.exports = TimeStep;