Saturday 24 August 2002

Pic of the day: Screenshot from Dasher, a.k.a. "Attack of the killer alphabet". It is not a children's game. Or not intentionally. It is however child's play.

Dasher

Have you ever thought that writing on a computer should be like a video game, not like a chicken feeding? Then you are ready for Dasher, a whole new concept in text entry. Available for various platforms, including Windows and the Pocket PC, it lets you catch letters of the alphabet as they slide towards you. So far it may sound looney. But here's the small thing that makes it all worthwhile: The letters are in boxes sized according to how likely they are to show up. For instance after "T", the box with "h" fills a pretty big part of the screen, and you can see a couple of vowels rushing up behind it.

The game ... er, text entry tool, does not (by default) work by looking up in a dictionary. Instead it uses a database of how likely any letter is to come after the preceding 4 letters. This is very much unique for each language. For instance in Norwegian, the letter "h" is not likely to come after "t" except in compound words. In English it is almost as likely as not. But that's just one letter. Dasher looks at five at a time. So if the preceding 4 letters are " and" then it supplies a space as the biggest block by far, since the five letters " and " occur very frequently in English. Similarly, after " tha" you will see "t" and "n" come rushing up, while "r" is holding back and "x" doesn't even bother to show up unless you go hunting way over in the left field.

The first hour or so you are likely to stay trapped in the video game metaphor. Watching and catching the letters is an enjoyable experience in itself, and it is easy to forget what you meant to write. The irony here is that Dasher doesn't become truly useful until it gets boring.

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Dasher is not without its problems, at least in its current not quite finished version. For some reason it doesn't seem to support comma or apostrophe, both of them heavy hitters in my prose. Nor quotation marks and other special characters (except period). If there is some way to add them, it is so non-obvious that I have still not found it. This, I am afraid, could be a "killer application" killer. Hopefully this will be added in a later release. At least the Pocket PC version has support for numbers: The digits are lined up in a specially colored block after the capital letters. (In the standard Windows version, there are not even capital letters until you enable them in the config menu. Be sure to do that before you test the game. Text entry tool.

I doubt Dasher will ever make it as a replacement for the keyboard on your home PC. But things suddenly change when we get to the pocket PC. I have one, and I have tried Dasher there. The difference between Dasher and a tiny "peck on the screen" keyboard is much less, even with minimal training. The problem is that it takes up all the screen space so you cannot see the document you are working on. Then again, if you need to constantly read the document while writing it, you may be in trouble anyway... And it is undoubtedly cuter.

Dasher is likely to become the standard text entry tool for the severely movement challenged. Tests have shown that it can actually be controlled by the eye muscles alone, and allow decent "typing" speed at that. Or if you have enough finger movement to use a track ball, you are all set and can do as well as a fully functional body.

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I've saved one major reason why you should try Dasher: It is free. More exactly it is GNU licensed, so it is bound to remain free and anybody is allowed to tinker with the source code to make a better Dasher, if they think they can. You don't even need to give them your e-mail address, though they politely ask for it (along with your nationality). It is hard to see what you could lose, except your sleep and sanity, good name and reputation ...
http://www.inference.phy.cam.ac.uk/dasher/