rafscroll – chain your scroll events to requestAnimationFrame

new rafscroll(function() { // Do your thing here. }); Your monitor refreshes at 60 frames per second (fps). Scroll events, on the other hand, do not. Chaining your scroll events to a requestAnimationFrame ensures that your transitions and animations will refresh each time the monitor refreshes, rather than each time a scroll event is fired. […]

Blackfire Profiler

Blackfire Profiler automatically instruments your code to gather data about consumed server resources like memory, CPU time, and I/O. But Blackfire Profiler is more than figures; its interactive Callgraphs make it straightforward to find bottlenecks and improve performance. Moreover, profile comparisons let you understand the impact of your changes. Blackfire Profiler β€” Fire up your […]

PerfMap: front-end performance heatmap

A bookmarklet to create a front-end performance heatmap of resources loaded in the browser using the Resource Timing API. Wait for a page to fully load and then click the bookmarklet to overlay a performance heatmap. A browser with support for the Resource Timing API is required. PerfMap: front-end performance heatmap →

Fixing a parallax scrolling website to run in 60 FPS

I recently visited a parallax scrolling website that was just one of thousands of different parallax scrolling websites out there. One thing that I immediately noticed was that the scrolling FPS of that page was really bad. I suspected that there would be room for improvement in their parallax implementation, and I wanted to take […]

CSS `will-change` Property

#header { will-change: opacity; } Modern CSS renderers perform a number of complex optimizations in order to render webpages quickly and efficiently. Unfortunately, employing these optimizations often has a non-trivial start-up cost, which can have a negative impact on the responsiveness of a page. The will-change property defined in the CSS Will Change Module allows […]

Velocity.js – Accelerated JavaScript animation

Velocity is a jQuery plugin that re-implements $.animate() to produce significantly greater performance (making Velocity also faster than CSS animation libraries) while including new features to improve animation workflow. Velocity includes all of $.animate()’s features while packing in color animation, transforms, loops, easings, sequences, and scrolling. Velocity is the best of jQuery, jQuery UI, and […]

Parallax Done Right

Parallax has become, for better or worse, an increasingly popular web trend. Done right, it feels awesome. The problem is, a vast majority of sites using parallax suffer from terrible scroll performance. A good refresher on how to do high performance animations Parallax Done Right → Related: High Performance Animations → 2D transform’s translate() vs […]