Calculate FPS in Canvas using requestAnimationFrame

Question

How could I calculate the FPS of a canvas game application? I\'ve seen some examples, but none of them use requestAnimationFrame, and im not sure how to apply their solution

Answer 1

Actually none of the answers were sufficient for me. Here is a better solution which:

• Use's performance.now()
• Calculates the actual average fps per second
• Average per second and decimal places are configurable

Code:

// Options
const outputEl         = document.getElementById('fps-output');
const decimalPlaces    = 2;
const updateEachSecond = 1;

// Cache values
const decimalPlacesRatio = Math.pow(10, decimalPlaces);
let timeMeasurements     = [];

// Final output
let fps = 0;

const tick = function() {
  timeMeasurements.push(performance.now());

  const msPassed = timeMeasurements[timeMeasurements.length - 1] - timeMeasurements[0];

  if (msPassed >= updateEachSecond * 1000) {
    fps = Math.round(timeMeasurements.length / msPassed * 1000 * decimalPlacesRatio) / decimalPlacesRatio;
    timeMeasurements = [];
  }

  outputEl.innerText = fps;

  requestAnimationFrame(() => {
    tick();
  });
}

tick();

JSFiddle