A little bit of Friday silliness for you, wherein I manage to combine two recent pastimes, hacking the MetaWatch and playing Minecraft, by pulling a piece of game UI out into the real world.

Lately I’ve been experimenting with the possibilities of Bluetooth watches. While I was fooling with Travis Goodspeed’s PyMetaWatch library for talking to the MetaWatch from Python code on your PC, I remembered a fun hack that my friend Michael Dales had done to control lights in the real world from actions and switches in the virtual world of Minecraft.

Minecraft is an engrossingly open-ended game that involves exploring caves for minerals, then using those materials to build more tools and buildings. To complicate matters, there’s a day/night cycle, and night time brings zombies, skeletal archers, and other nasty ssssurprises. The upshot is that it’s a lot safer to travel during the day.

If you’re mining deep in a cave, though, how do you know when it’s safe to emerge from your spelunking to haul your loot home? Notch, the game’s creator, eventually added the ability to craft an astronomical clock in the game to tell you what time of day it was.

So, how did I get it on my wrist? Here’s the crafting recipe for this hack: I wrote a little mod for the Minecraft server that spit out the virtual world’s time of day, using V10lator’s lib24time library and the gratifyingly straightforward Bukkit Minecraft modding system. From there, I have a Python script that uses PIL and the assets from the game to render an approximation of the Minecraft watch at the given time of day.

Finally, I’m using my fork of PyMetaWatch to send the image from my Mac to the watch via bluetooth.

It works, but it’s very laggy right now. (Eagle-eyed Minecraft fans might have noticed that my screenshot above is more evocative than accurate.) The slowdown seems to be somewhere in the PyMetaWatch/lightblue combo, which is taking an agonizingly long time to send a bitmap to the watch. I can generally send a bitmap from my Android phone in less than a second, I suspect that either lightblue is configuring the bluetooth RFCOMM link for a ridiculously low speed, or there’s some overhead in the PyObjC bridge that it relies on. Let me know if you have any ideas.

Update (Sept. 17): Today I tried a different tack, involving an Android app loading the clock image from the Mac over wifi and sending it to the watch via MetaWatchManager, and it worked much better. Here are a couple more pictures showing the watch time more or less synced up with the time on the in-game clock: