Pinderkent

Today at Reddit there was a posting about a simple 2D bouncing ball physics simulation written in JavaScript. This is the latest example of a simple JavaScript demo that, for some inexplicable reason, gets many people excited.

Thankfully, there are some other people who see these JavaScript demos for what they truly are: something to not get excited over! One of the best replies to that Reddit posting points out how it ought to be easier to make such demos in JavaScript than in other programming languages. And that poster also correctly points out that there's no need to get excited over such trivial applications.

Another reply pointed out the demo's extreme similarity to Pong, a game from the early 1970s. It's also somewhat similar to Breakout, a game from the mid-1970s. Indeed, many of these JavaScript demos are often no more original than what we had over 30 years ago. Mind you, the equivalents from 25 or 30 years ago ran on computers with a small fraction of the processing power and memory of a typical desktop PC today. The developers back then actually had significant hardware constraints, unlike those behind the JavaScript demos of today.

Several others noted just how poorly this demo performs, even on modern systems when using modern Web browsers. One such user reported that it could animate at most five balls on his laptop with an Intel Atom processor before it became unusable. Although Atom processors aren't the most powerful by any means, they should be more than sufficient for the computation necessary to perform basic 2D collision detection and animation.

One user reported that it lagged in Firefox 3 on Mac OS X. Another reported performance problems while using Firefox on Linux.

As usual, we can't have a discussion about JavaScript demos or games without mentioning the unreasonable memory requirements of these demos. I think that poster's claim of 200 MB of RAM usage is, unfortunately, quite realistic. Using Firefox 3.0.5 on Linux, just starting up Firefox resulted in a process that was using 456 MB of virtual memory (as reported by top), with a resident size of 75 MB. Drawing a slightly downward sloping horizontal line, which allowed for approximately three balls to be on the screen simultaneously at the default drop rate, bumped the virtual memory usage up to 523 MB, with 176 MB resident. And extending that line somewhat longer, to allow about eight simultaneous bouncing balls at the default drop rate, bumped the memory usage up to a whopping 587 MB virtual, with 204 MB resident. After leaving the demo running for several minutes, it had stabilized at that point.

I don't think I'll ever understand how somebody could possibly become excited, even in the slightest, over these sorts of JavaScript demos. What they demonstrate was usually demonstrated better, using a fraction of the resources and processing power, two or three decades ago! The performance is typically terrible, even on higher-end PCs a month or two old, using modern Web browsers. It's not surprising to see 100% CPU usage, as well as hundreds of megabytes of memory being used. So in the end, all they do is exhibit essentially no innovation, poor performance, poor resource usage and prove yet again how awful JavaScript is for such simple applications. In short, there's absolutely nothing to be "amazed" or "excited" about with these JavaScript demos.