add get average frame rate fields to frame rate monitor class

packages/engine/Source/Scene/FrameRateMonitor.js

@@ -17,7 +17,8 @@ import TimeConstants from "../Core/TimeConstants.js";
  *
  * @param {object} [options] Object with the following properties:
  * @param {Scene} options.scene The Scene instance for which to monitor performance.
- * @param {number} [options.samplingWindow=5.0] The length of the sliding window over which to compute the average frame rate, in seconds.
+ * @param {number} [options.samplingWindow=5.0] The length of the sliding window over which to compute the average frame rate, in seconds,
+ * for the purpose of calculating if the frame rate is lower or higher than the minimum frame rate threshold.
  * @param {number} [options.quietPeriod=2.0] The length of time to wait at startup and each time the page becomes visible (i.e. when the user
  * switches back to the tab) before starting to measure performance, in seconds.
  * @param {number} [options.warmupPeriod=5.0] The length of the warmup period, in seconds. During the warmup period, a separate
@@ -28,6 +29,8 @@ import TimeConstants from "../Core/TimeConstants.js";
  * @param {number} [options.minimumFrameRateAfterWarmup=8] The minimum frames-per-second that are required for acceptable performance after
  * the end of the warmup period. If the frame rate averages less than this during any samplingWindow after the warmupPeriod, the
  * lowFrameRate event will be raised and the page will redirect to the redirectOnLowFrameRateUrl, if any.
+ * @param {number} [options.averageFrameRateWindow=10] The length of the sliding window over which to compute the average frame rate, in
+ * number of frames, for the purpose of calculating and displaying <code>averageFramesPerSecond</code>
  */
 function FrameRateMonitor(options) {
  //>>includeStart('debug', pragmas.debug);
@@ -47,6 +50,15 @@ function FrameRateMonitor(options) {
  FrameRateMonitor.defaultSettings.samplingWindow
  );
 
+ /**
+ * Gets or sets the length of the sliding window over which to compute the average frame rate, in seconds.
+ * @type {number}
+ */
+ this.averageFrameRateWindow = defaultValue(
+ options.averageFrameRateWindow,
+ FrameRateMonitor.defaultSettings.averageFrameRateWindow
+ );
+
  /**
  * Gets or sets the length of time to wait at startup and each time the page becomes visible (i.e. when the user
  * switches back to the tab) before starting to measure performance, in seconds.
@@ -93,19 +105,23 @@ function FrameRateMonitor(options) {
  this._nominalFrameRate = new Event();
 
  this._frameTimes = [];
+ this._averageFrameRateTimes = [];
  this._needsQuietPeriod = true;
  this._quietPeriodEndTime = 0.0;
  this._warmupPeriodEndTime = 0.0;
  this._frameRateIsLow = false;
  this._lastFramesPerSecond = undefined;
+ this._averageFramesPerSecond = undefined;
  this._pauseCount = 0;
 
  const that = this;
+ console.log("here 1");
  this._preUpdateRemoveListener = this._scene.preUpdate.addEventListener(
  function (scene, time) {
  update(that, time);
  }
  );
+ console.log("here 2");
 
  this._hiddenPropertyName =
  document.hidden !== undefined
@@ -165,6 +181,7 @@ FrameRateMonitor.defaultSettings = {
  warmupPeriod: 5.0,
  minimumFrameRateDuringWarmup: 4,
  minimumFrameRateAfterWarmup: 8,
+ averageFrameRateWindow: 10,
 };
 
 /**
@@ -233,6 +250,9 @@ Object.defineProperties(FrameRateMonitor.prototype, {
 
  /**
  * Gets the most recently computed average frames-per-second over the last <code>samplingWindow</code>.
+ * The <code>samplingWindow</code> begins after the expiration of the <code>quietPeriod</code>, and restarts
+ * each time the <code>minimumFrameRateDuringWarmup</code> or <code>minimumFrameRateAfterWarmup</code> threshold
+ * is crossed, or <code>pause</code> is invoked.
  * This property may be undefined if the frame rate has not been computed.
  * @memberof FrameRateMonitor.prototype
  * @type {number}
@@ -242,6 +262,33 @@ Object.defineProperties(FrameRateMonitor.prototype, {
  return this._lastFramesPerSecond;
  },
  },
+
+ /**
+ * Gets the most recently computed average frames-per-second over the last number of frames specified
+ * in <code>averageFrameRateWindow</code>.
+ * This property may be undefined when the scene first loads until <code>averageFrameRateWindow</code>
+ * has passed. After <code>averageFrameRateWindow</code> has passed the property will be continuously
+ * available, the limitations specified for <code>lastFramesPerSecond</code> do not apply to it.
+ * @memberof FrameRateMonitor.prototype
+ * @type {number}
+ */
+ averageFramesPerSecond: {
+ get: function () {
+ if (this._averageFrameRateTimes.length !== this.averageFrameRateWindow) {
+ this._averageFramesPerSecond = undefined;
+ } else {
+ const windowSize = this.averageFrameRateWindow - 1;
+ const averageTimePerFrame =
+ (this._averageFrameRateTimes[0] -
+ this._averageFrameRateTimes[windowSize]) /
+ windowSize;
+ const fps =
+ 1 / (averageTimePerFrame * TimeConstants.SECONDS_PER_MILLISECOND);
+ this._averageFramesPerSecond = fps;
+ }
+ return this._averageFramesPerSecond;
+ },
+ },
 });
 
 /**
@@ -310,12 +357,17 @@ FrameRateMonitor.prototype.destroy = function () {
 };
 
 function update(monitor, time) {
+ const timeStamp = getTimestamp();
+
+ monitor._averageFrameRateTimes.unshift(timeStamp);
+ if (monitor._averageFrameRateTimes.length > monitor.averageFrameRateWindow) {
+ monitor._averageFrameRateTimes.pop();
+ }
+
  if (monitor._pauseCount > 0) {
  return;
  }
 
- const timeStamp = getTimestamp();
-
  if (monitor._needsQuietPeriod) {
  monitor._needsQuietPeriod = false;
  monitor._frameTimes.length = 0;

packages/engine/Source/Scene/ScreenSpaceCameraController.js

@@ -578,7 +578,7 @@ function handleZoom(
  const minDistance = distanceMeasure - minHeight;
 
  let fpsMultiplier = 1;
- const fps = object.frameRateMonitor.lastFramesPerSecond;
+ const fps = object.frameRateMonitor.averageFramesPerSecond;
  if (fps) {
  fpsMultiplier = 30 / fps;
  }