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bounding brokenness

OS X mouse strangeness

So I decided to upgrade my Apple notebook’s OS X install to Lion earlier this week. Due to an unfortunate series of events, partly my fault, mostly Apple’s, my MBR was corrupted and my Windows install became unbootable. So I was stuck with OS X for a few days until I had the time to fix my Windows install.

I’ve been running Windows and Linux with mouse acceleration turned off ever since I started using a high-precision mouse (it’s ugly, but really precise and comfortable to use), and I’ve come to appreciate it a lot. OS X’s acceleration curve is very different from Windows, which is fine, but the real problem is that there’s no built-in way to turn it off. Luckily, there’s a $0.99 app on the Mac App Store which lets you disable acceleration. That, and bumping up the resolution of the mouse a notch, made things better.

Things still felt strange, though, and once I fixed my Windows install and booted into it I realized why. OS X has severe input lag with the mouse. According to this blog post, the lag (which has been confirmed to exist by an Apple engineer) exists on all OS X installs, and on all mice and touchpads, and is 32 milliseconds. Now, 32 milliseconds might not sound like much, but I can easily tell the difference between 30 frames per second (33 ms/frame) and 60 FPS (17 ms/frame) while playing a game.

Windows and Linux do not have this problem: the input lag is less than the screen’s refresh rate, so the pointer is locked on to the mouse. Both feel significantly more responsive as a result.

If you’re using OS X now and are sensitive to such things, I suggest switching away until it’s fixed. You’ll be delighted you did.