Added in forceSetTimeout fps value (phaserjs#4179)

Author: photonstorm

CHANGELOG.md

@@ -11,6 +11,7 @@
 * `Tilemap.getImageLayerNames` is a new method that returns a list of all valid imagelayer names loaded in the Tilemap (thanks @Olliebrown)
 * `Tilemap.getObjectLayerNames` is a new method that returns a list of all valid objectgroup names loaded in the Tilemap (thanks @Olliebrown)
 * `Tilemap.getTileLayerNames` is a new method that returns a list of all valid tilelayer names loaded in the Tilemap (thanks @Olliebrown)
+* When `forceSetTimeOut` is set to `true` in the Game Config, you can now set the target frame rate by setting the `fps.target` value (thanks @pavels)
 
 ### Updates
 

src/core/TimeStep.js

@@ -447,7 +447,7 @@ var TimeStep = new Class({
 
         this.callback = callback;
 
-        this.raf.start(this.step.bind(this), this.forceSetTimeOut);
+        this.raf.start(this.step.bind(this), this.forceSetTimeOut, this._target);
     },
 
     /**

src/dom/RequestAnimationFrame.js

@@ -82,6 +82,17 @@ var RequestAnimationFrame = new Class({
          */
         this.lastTime = 0;
 
+        /**
+         * The target FPS rate in ms.
+         * Only used when setTimeout is used instead of RAF.
+         *
+         * @name Phaser.DOM.RequestAnimationFrame#target
+         * @type {number}
+         * @default 0
+         * @since 3.21.0
+         */
+        this.target = 0;
+
         var _this = this;
 
         /**
@@ -119,7 +130,7 @@ var RequestAnimationFrame = new Class({
         {
             var d = Date.now();
 
-            var delay = Math.max(16 + _this.lastTime - d, 0);
+            var delay = Math.min(Math.max(_this.target * 2 + _this.tick - d, 0), _this.target);
 
             _this.lastTime = _this.tick;
 
@@ -139,8 +150,9 @@ var RequestAnimationFrame = new Class({
      *
      * @param {FrameRequestCallback} callback - The callback to invoke each step.
      * @param {boolean} forceSetTimeOut - Should it use SetTimeout, even if RAF is available?
+     * @param {number} targetFPS - The target fps rate (in ms). Only used when setTimeout is used.
      */
-    start: function (callback, forceSetTimeOut)
+    start: function (callback, forceSetTimeOut, targetFPS)
     {
         if (this.isRunning)
         {
@@ -151,6 +163,8 @@ var RequestAnimationFrame = new Class({
 
         this.isSetTimeOut = forceSetTimeOut;
 
+        this.target = targetFPS;
+
         this.isRunning = true;
 
         this.timeOutID = (forceSetTimeOut) ? window.setTimeout(this.stepTimeout, 0) : window.requestAnimationFrame(this.step);