Function calculateStats

apps/desktop/src/routes/editor/PerformanceOverlay.tsx:49–111

()

	});

	const calculateStats = (): FrameStats => {
		const now = performance.now();

		while (
			frameTimestamps.length > 0 &&
			now - frameTimestamps[0] > STATS_WINDOW_MS
		) {
			frameTimestamps.shift();
		}

		while (frameIntervals.length > MAX_TIMESTAMPS) {
			frameIntervals.shift();
		}

		if (frameTimestamps.length < 2) {
			return {
				fps: 0,
				avgFrameMs: 0,
				minFrameMs: 0,
				maxFrameMs: 0,
				jitter: 0,
				droppedFrames: droppedFrameCount,
				totalFrames: totalFrameCount,
			};
		}

		const windowMs = now - frameTimestamps[0];
		const fps =
			windowMs > 0 ? ((frameTimestamps.length - 1) / windowMs) * 1000 : 0;

		let avgFrameMs = 0;
		let minFrameMs = Number.MAX_VALUE;
		let maxFrameMs = 0;

		if (frameIntervals.length > 0) {
			let sum = 0;
			for (const interval of frameIntervals) {
				sum += interval;
				minFrameMs = Math.min(minFrameMs, interval);
				maxFrameMs = Math.max(maxFrameMs, interval);
			}
			avgFrameMs = sum / frameIntervals.length;
		}

		let jitter = 0;
		if (frameIntervals.length > 1) {
			let varianceSum = 0;
			for (const interval of frameIntervals) {
				varianceSum += (interval - avgFrameMs) ** 2;
			}
			jitter = Math.sqrt(varianceSum / frameIntervals.length);
		}

		return {
			fps,
			avgFrameMs,
			minFrameMs: minFrameMs === Number.MAX_VALUE ? 0 : minFrameMs,
			maxFrameMs,