By the time you read this I'll be back home again after the#

Sun, 03 Aug 2003 22:00:33 +0000

By the time you read this I'll be back home again after the UKUUG's Linux 2003 summer conference, at which I was speaking on "Native threads for SBCL". The paper is at http://www.linux.org.uk/~dan/linux2003/; I'm told it's also on the conference CD and may also end up on the UKUUG web site eventually.

And the slides. Well ...

On Wednesday I roughed out how many slides I should do (one for every two minutes) and the titles. By mid-afternoon on Friday I'd more or less decided on the body content too. This was all in a text file, so should be easy to turn it into a presentation, were it not for some fairly strange requirements I have for a usable presentation graphics tool.

• Able to run happily on my laptop (only 128Mb RAM, much of which is already used by Emacs and Mozilla Firebird). This makes OpenOffice and the like a non-starter.

• Easy to use without a mouse, because I only have the touchpoint mouse substitute. Which works perfectly for most of my mouse use (window focus) but starts to get tedious for any work demanding more accuracy than clicking on web links.

• You're thinking that magicpoint fits the bill, right. Well, it would do, but, please, God, don't make me have to use magicpoint again. It has that strange m4-like property of making the easy things easy and the slightly more difficult things (like, say, switching to typewriter font and back on the same slide without either breaking my carefully indented code or putting the following bullet point somewhere utterly weird) nightmarishly awkward. And the documentation is kind of iffy.

So, after the Scottish Buffet (a Scottish Buffet, it appears, is what we in England call a "sit-down meal", although no less tasty for all that) on Friday evening I headed back to my room, paged through the slide text for a few minutes, and when I next looked up it was early on Saturday morning and I'd written the bare bones of a presentation graphics program using CL - my first CLX program, too. (Yes, that's right, I maintain(sic) a CLX port for SBCL despite never yet having written anything that uses it)

Matters arising, in no particular order

• There's a bug in CLX's with-gcontext macro. Or at least, it certainly doesn't do as I ask

• I need to add a word-wrap algorithm. Eventually (I also had a conference to attend while developing it, so there was limited concentrated hacking time available) I had to stop fiddling with it and just add line breaks to the source file. Newlines are kind of dodgy, too, and I also need to find a less blocky title font.

• I used it for the presentation. It worked, and didn't crash. The screensaver leapt into action a couple of times - I should add an onscreen "you have lingered on this slide too long" indication, because having the whole thing turn black is a bit unsubtle

• CLX programming is surprisingly painless, at least given the manual. The next version of telent clx will include such a thing, based on the manual at Gilbert Baumann's site

• That URL again: http://www.linux.org.uk/~dan/linux2003/. If you want to play with the presentation thing, viewer.lisp is the appropriate file. Needs SBCL CLX for open-default-display, which you could easily replace with open-display cruft if you're running some other Lisp.

• It may be subjected to more hacking in future: all depends on how often i find I need to give presentations. The observant will note from the defpackage form that I've called it Acclaim.

More about the conference itself later.