Merge pull request phaserjs#4989 from jjcapellan/syncToRender

New property Arcade.World.fixedStep

Author: photonstorm

src/physics/arcade/World.js

@@ -154,6 +154,17 @@ var World = new Class({
          */
         this.fps = GetValue(config, 'fps', 60);
 
+        /**
+         * Should Physics use a fixed update time-step (true) or sync to the render fps (false)?. 
+         * False value of this property disables fps and timeScale properties. 
+         *
+         * @name Phaser.Physics.Arcade.World#fixedStep
+         * @type {boolean}
+         * @default true
+         * @since 3.23.0
+         */
+        this.fixedStep = true;
+
         /**
          * The amount of elapsed ms since the last frame.
          *
@@ -927,6 +938,13 @@ var World = new Class({
         //  Will a step happen this frame?
         var willStep = (this._elapsed >= msPerFrame);
 
+        if(!this.fixedStep)
+        {
+            fixedDelta = delta * 0.001;
+            willStep = true;
+            this._elapsed = 0;
+        }
+
         for (i = 0; i < bodies.length; i++)
         {
             body = bodies[i];