I walk out to Tesco and back at lunchtime, and suffer not a whisper of hayfever. Come back to the office, sit at my desk in a clean air-conditioned room, and now I feel a sneezing fit coming on.

I also got bellowed at by louts cycling on the pavement on my way to buy lunch. In such situations I tend to relieve my annoyance by imagining that I could wave a hand and cause some vaguely appropriate justice to magically apply itself, but in this case I was particularly annoyed by being unable to think of anything suitably poetically just. For example, if I could have waved a hand and caused all the wheels to fall off their bikes, that would have been momentarily satisfying but would also have meant they were still being obnoxious near me rather than receding at high speed. Twanging them half way to Scotland would have preserved the latter property but would only have inflicted them on some other poor innocent. Nuking from orbit is probably excessive.

In other news, this is the kind of headline that makes me sorry Have I Got News For You isn't currently on air: http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2005/08/02/wteapot02.xml.

This week I have been doing stuff at work, in all seriousness, which qualifies as an implementation of a design principle invented some years ago as a 1st April joke.

Also this week I have written twenty-five thousand words (of developer documentation for my puzzle collection, since an unprecedented number of people simultaneously threatened to write additional games for it and I thought it might help if they all knew how to). This mostly consisted of just dumping the entire contents of my brain into a text editor; there was very little need to think hard about what I was writing, since I had it all pretty clear in my mind already and the limiting factor was how fast I could type it. Except that, as it turned out, the limiting factor was the bit of my brain through which knowledge has to be squeezed to turn it into linear sentences; at one point I found that part of my brain suffering fatigue, so that although I still had the knowledge in my head I just couldn't form it into coherent sentences to write it down – and yet I could still type, and program, and do anything that didn't require forming sentences. A very strange feeling, and not one I've had before. Sleep sorted it out, thankfully.

Sleep, however, has not been a respite from the general strangeness of the week, because it's also Strange Dreams Season. On the majority of mornings this week I've woken up and thought ‘huh?’. To give the most memorable example: on one night of this week I had a rather upsetting and nightmarish dream in which I was very distressed to find I'd lost the power to levitate objects with my mind. The odd thing was that, as well as (obviously) not having this power while awake, I hadn't even had it during the dream!

It might make a change to have a sensible few days. Then again, perhaps it would just be boring.

The question ‘who are you?’ came up in a memetic LJ quiz the other day, and I gave a somewhat flip answer, as did many of the other people who answered it.

As befits a Babylon 5 fan, I have actually given some real thought to this question from time to time, and I do have a more serious answer to it. So I thought I'd muse a little, in my customary armchair-philosophical fashion, on the question and what it means.

I just discovered an optical illusion. Never had that happen before; I've seen optical illusions and heard explanations of them, but this is the first time I've experienced an illusion I'd never seen before and had to work out why it happened for myself.

The background image on my Linux desktop is an indistinct fuzzy cloudy sort of pattern, because I rather like it and I find it very easy to visually distinguish sharply defined objects in front of it. Over this indistinct image I brought up a window for one of my more recent puzzle games, and played it in the normal way. When I'd finished, I leaned back in my swivel chair; and when I brought the chair forward again, I noticed a strange thing. The fuzzy cloudy background around the Dominosa window looked as if it was expanding! That is, not just expanding in the normal way you expect things to expand when your eyes move closer to them, but beyond that – it looked as if it was expanding relative to the screen and to the puzzle window.

I leaned back and moved forward again: same result. Of course the background didn't really expand, but it looked as if it was doing so for just the moment when my head was in motion towards the monitor.

My tentative explanation for the phenomenon is: the cloudy background I use doesn't look like a foreground object. It's more of a background thing, something that you expect to see at a very long distance (like, in fact, clouds). Now the apparent size of an object is inversely proportional to its distance from your eye[1]; so if you move your head twice as close to something it appears twice as big. So suppose I were looking at a foreground object in front of a distant background, and I moved my head sharply to put it twice as close to the foreground object. The apparent size of the foreground object would double, yet the apparent size of the background would barely change (since the relative change in my distance from it would be a tiny fraction of a per cent). So the foreground object would expand relative to the background, in my vision, and in particular a larger amount of background would be hidden from my view behind the foreground object. Thus, this is what my eye expected to see when I brought my head sharply towards a well defined foreground-looking object against an indistinct and cloudy-looking background; and when that didn't happen (because in fact both were displayed on the same monitor and their apparent sizes expanded at the same rate), my visual cortex must have initially assumed it to be because the background was physically expanding – as if the clouds themselves were changing in shape and size as I moved my head.

[1] (That is, in conventional flat-plane perspective; it gets fiddly and trigonometric if you start thinking in the more correct terms of angles subtended at the eye, but the flat plane approximation is adequate for this purpose.)

It's stopped happening now, annoyingly; I think my visual cortex must have figured out it was being had and adapted. Perhaps it was listening in on my conscious mind while I was working out what had happened.

I don't know if this illusion was specific to me or will happen for anyone else; so, in a spirit of experimentation, here's a snapshot of the desktop around the window in question: http://www.tartarus.org/~simon/20050723-illusion.png. To (hopefully) activate the illusion, arrange to move your head rapidly towards the image from a distance of (say) about 1m to (say) about 1/2 m. I found a good way to achieve this was to lean back in my swivel chair and then rapidly let it return to the upright position, but your mileage may vary. (This diary does not endorse dangerous leaning-back-on-chairs and accepts no liability for any injury incurred as a result. If in doubt, get a responsible adult to help you.)

My weekend was taken up almost entirely by my puzzle collection. The maintenance load for this is starting to ramp up, which is a bit scary for a software project intended to supply nothing more than a bit of fun.

On Saturday morning, marnanel posted a link to a rather fun Flash game, at which I took one look and thought ‘very nice, shame it runs in a huge web browser window and only has a fixed set of levels’ and promptly took steps to rectify the situation. By Saturday evening, ‘Untangle’ was part of my puzzle collection.

While I was writing that, three patches arrived in my inbox from various people: a bug fix, a speedup, and one implementing another new game. So I applied one, quibbled with another, and made a note of the things I'd need to polish before committing the third; and then, satisfied that I'd left myself enough notes that I'd remember what I was doing the next day, I wandered off to the Rivendell house-cooling.

On the way to the party I told myself I must try to avoid being a Puzzles bore; when I've been concentrating on one thing all day I tend to find it hard to change gear and start talking about something else. Didn't work, because of course people said things like ‘so what have you been up to recently’… And then claroscuro showed off her new mobile phone which is also a Palm, and of course someone has recently ported my puzzle collection to run on Palms, so she downloaded that and I actually got to see it run for the first time, which was kind of cool if also quite scary.

Slept badly on Saturday night; woke up before 8am the next day with good ideas running through my head, so I got up and went and polished the new third-party puzzle, ‘Black Box’, until it was committable, and committed it. Also I dug out the piece of magic CSS which Owen had written for me the other day, and used it to redesign the Puzzles web page so that you don't have to scroll down quite so far to get to the downloads. Then the rest of the day, until I headed Gallerywards for the usual Sundaying, was taken up with small polishings and fixes and emails pointing out mistakes in my recent work. Even at the Gallery I checked my email part way through the evening and discovered another patch I'd been sent, which I quickly checked and applied before going back to being sociable.

Considering that last week, before all this started, I had just implemented a new puzzle ‘Dominosa’, the net result is that (a) in the space of one week the collection has acquired three new puzzles and a new website design, and (b) I'm now simultaneously sick of the word ‘puzzles’ and unable to think about anything else!

I remember when the collection started; it had four games, running on two platforms. I always said that my aim was eventually to collect lots of games and have them all run on lots of platforms, but I felt a bit uncomfortable about it at the time because it really wasn't a very impressive collection – just a small webpage with big ideas. But now we have seventeen puzzles running on four platforms, which I think is actually pretty good going.

Bah. It's got all hot again; it's been very hard to get my brain into gear this week. The air conditioning at work helps, but not really enough.

Also my personal hayfever season seems to be beginning. I was hoping it'd hold off until August, but I suppose we're half way to August already…

Anyone pointing binoculars through my open kitchen window a couple of hours ago would have encountered a rather strange sight: a software engineer industriously chopping onions, while wearing a pair of blue-tinted Speedo swimming goggles. I had suddenly remembered that I had these in a cupboard along with some very elderly swimwear, and decided in a spirit of experimentation to see how they worked as impromptu eye protection against onion vapour.

As protection, they worked pretty well; the onions I bought this week are of a type which usually produce a well-above-average quantity of noxious vapour, and yet my eyes didn't sting perceptibly at all. Unfortunately, they misted up rather quickly (which I'd always assumed was an effect of wearing them in water, but apparently not) and so my vision was significantly impaired; I'm not totally convinced it was a worthwhile tradeoff.

My goggle-impaired vision was particularly inconvenient while trying to work out what had happened to my garlic crusher, which decided today was a good day to die. I put a clove of garlic in, worked the handle as usual, and was rather surprised to find a whole clove of garlic arriving on the far side of the mesh. This is where the Speedo MurkyVision™ didn't help; if I hadn't still had the goggles on I probably would have noticed quite quickly that the entire mesh had broken off the frame and swung to one side. As it was I stared at the assembly in some confusion for several minutes before finally working out – mostly by touch – what was going on. This is now the second garlic crusher I've broken by means of what I thought was perfectly normal use, viz. using it to crush garlic. (Though the previous one was much more impressive, since the mesh basket was made of thick metal and yet somehow a normal garlic-crushing level of force managed to bend it so far out of shape that it never worked again.) I'm almost tempted to wonder if I've missed some vital point about how to use the things.

Still, a garlic crusher doesn't do anything that a sharp knife and some patience can't do in a pinch, so I got my food in the end. Phew.

I had a thought yesterday about guessing games.

It sounds like a fun idea on paper, if a bit brain-bending; also it strikes me that someone must have thought of it, or something like it, before. If not (and perhaps even if so), I wonder if it's worth a try.

So Luke and Darth Vader are having their lightsaber duel in Cloud City, and Vader is just about to reveal Luke's parentage and offer him co-rulership of the Galaxy…

… but at that point he might perfectly well have thought ‘oh, sod it’ and just killed him. Easier dead than son.

I could tell I was a geek, because as I sat in fanf and rmc28's wedding this afternoon, I was sure that I was supposed to be thinking solemn thoughts about love, lifelong companionship, and possibly God. Instead I found myself – as usual at weddings, come to think of it – mostly worrying about the transactional integrity of the procedure.

What happens if the bride and groom have exchanged vows but haven't yet been pronounced man and wife, and then the ceremony is unavoidably interrupted by (for example) the church catching fire: does the wedding roll back, or commit? What happens if the interruption occurs after they've been pronounced man and wife but before signing the register: are they married in the eyes of God but not the Law, and might they have to rectify the legal side at a registry office at some later date? And worse still, what happens if one has made the vows to the other but not vice versa: do you end up with one person having sworn in the sight of God to be faithful to someone who has sworn nothing in return, and thus (at least theoretically) the latter is able to go and marry someone else leaving the former poor sap in a bit of a bind? It all seems terribly fraught with danger; there should be proper backups kept in case of accident.

Anyway; fortunately nothing of the sort happened and the happy couple are now safely married. I'm off out to the bring-and-share-food reception soon, but first I'm briefly back at home so as to cook the food I'm bringing.

Extra points to this wedding for having the hymn music in the service booklet as well as the words, so that I actually knew what I was supposed to be singing; unfortunately it turned out that I'd forgotten how key signatures worked (or at least couldn't dig it out of my dusty mental music-theory attic fast enough, perhaps because I was still worrying about wedding atomicity :-), but I got there in the end.

It was the Calling yesterday, and I completely forgot. That's unheard of for me since I started going back there. I've occasionally missed one due to other engagements, illness, bad mood or sheer tiredness, but this is the first time I've missed the Calling simply because I clean forgot it was on. I feel astonishingly silly.

I have a vague feeling that the unconventional timing of the last Calling might have thrown my normally reliable ability to count to two weeks, but even so that's not much of an excuse. So if anyone reading this would have expected, or perhaps even liked, to see me at the Calling, let it be known that I would have been there had I not been a complete scatterbrain.

I think I'm going to go and sit quietly on a sofa now. With any luck I won't be able to get that wrong.

This seems to be the month for me encountering TV programmes which I can't quite believe are real.

Recently I heard of ‘Sudoku Live’, and I was honestly convinced it was a joke. Then the Gallery caught thirty seconds of it on Friday evening; it isn't. Someone has genuinely turned Sudoku into live television.

I assumed that was a one-off, but today my credulity was strained again by catching sight of a newspaper's TV listing which contained ‘Ann Widdecombe To The Rescue’.

At times like this I want to say ‘you couldn't make it up’, except that somebody evidently could!

For the past few days I've felt very tired and apathetic. This morning, after what seemed like an excellent night's sleep, I feel as if what I need is to go straight back to bed for another excellent night's sleep. This is not normal, so I assume I'm ill in some fashion.

It might be a nonspecific viral uurgh of some sort, but actually I'm rather tempted to speculatively correlate it with accidentally being fed gluten on Tuesday evening. I'm not quite sure how I feel about that. On the one hand it would be pretty annoying to think that my entire week could be ruined by a small amount of undeclared soy sauce in a home-made beefburger, but on the other hand I've never before seen any perceptible symptoms of coeliac disease and it was also rather annoying to think that I was going through all this dietary hassle on nothing but a gastroenterologist's say-so; so it might be a relief to think that I am actually getting some benefit out of it.

Meanwhile at work, almost everybody in the office has disappeared to go to a marketing presentation. I avoid these (they're voluntary) on the grounds that marketing bores the wossnames off me; but when nobody else is in the room for an hour I occasionally start to wonder if I've missed some vital point and they're actually more interesting than they sound. Or if everyone here is actually expected to go to these presentations and I'm blighting my future career by sitting here doing real work instead. Or, in fact, any of the other collection of feelings normally grouped together under the umbrella term ‘peer pressure’. Bah. I avoided most of that at school (the really cool people smoke and drink already, the middling-cool ones can be persuaded, but nobody has any interest in even trying to persuade the geeky outcasts) and it's slightly annoying to find it turning up in the workplace :-/

I'm starting to get annoyed by the fact that I'm so biochemically unstable.

Coeliac disease is the obvious starting point: not only can I not eat obviously wheaty things like (ordinary) bread and pasta, but I have to be insanely careful of cross-contamination from things containing trace amounts of gluten. This makes it very difficult to eat anything I haven't cooked myself, either at restaurants or at friends' houses; there are only about three or four people I currently trust to cook for me, and it's annoyingly common when I risk letting someone else do it that I get most of the way through a delicious meal and then they tell me what one of the ingredients was and it rings an alarm bell.

In addition to that, as some of my readers will already know, I'm hypersensitive to caffeine. I haven't always been: I can pin it down reasonably accurately to mid-2001, at which point I suddenly started to find that drinking any perceptible amount of coffee gave me something approaching a panic attack. These days I find that a cup of decaff gives me something like a normal caffeine buzz, four cups of decaff make me uncomfortably jittery, and the last time I tried drinking even half a cup of ordinary coffee I got panicky and paranoid. (Oddly, though, I seem to be fine with tea, so perhaps it's not the caffeine but something else in coffee specifically.)

I'm currently off alcohol, because I suspect it of interfering with my sleep, and since some of the recent hot weather has certainly been interfering with my sleep I decided to stay sober for a few weeks on the basis that my sleep needed all the help it could get. (Particularly annoying is that last week I found some Hambleton GFB – a gluten-free real ale which I've wanted to try for a while – in Asda, and now I have to wait until I think I'm ready to go back on booze before I can drink it!)

I'm also unpleasantly hypersensitive to cannabis smoke. This one doesn't cause me a problem very often, thankfully; I think there have now been a total of two occasions on which I've been in the same room as someone smoking a joint and it's affected me. The effects are hard to describe, but I definitely don't like them, and in particular they seem to involve disturbed sleep. (The other problem with this one is that not everybody is willing to admit to smoking dope, it being technically illegal and all that, so it can be socially difficult to arrange to be warned in advance so I can leave the room! Not being able to get advance warning from the smell doesn't help there either.)

This is just getting beyond a joke. It's particularly aggravating when several of these things cause me trouble in the same evening; occasionally I feel that if I have to say one more time ‘I'm sorry, I can't eat / drink / go anywhere near that, I'm intolerant of it’ I'm just going to scream. It's also annoying because five years ago I had none of these problems; I was fine with alcohol and caffeine, coeliac disease was something that happened to my grandfather but not to anyone else I knew, and I might or might not have been hypersensitive to cannabis but it didn't matter because nobody I knew used it. Somewhere between then and now I've turned from a reasonably robust human being into someone brittle and fragile who has to avoid any number of perfectly normal things because they variously cause me to get cancer, lose sleep, panic or (I wouldn't be too surprised) spontaneously combust.

It's stuff like this that makes me particularly cross with Creationists. I can only assume that most fundie Creationists are extremely physically fit and healthy and have no food intolerances, no minor ailments, no dodgy muscles or joints, no missing senses and no aggravating psychological quirks; because some days I'm incapable of inhabiting this body or this mind for more than half an hour at a time without it being totally and infuriatingly obvious to me that it was designed very badly by trial and error. Intelligent design? Pah. You can stick it. If there was an act of intelligence in the design of the human body, it was the one where the designer realised that a sizable portion of the species would still worship him no matter what he did, and hence there was no reason he couldn't get away with doing a quick and shoddy job and sloping off early to the pub.

Games of hidden information are very weird in their randomness.

Minesweeper, of course, is well known to be annoying for its randomness, which is why I went to the effort of writing a version that didn't require random guesswork. When you have no choice but to take a risk, it's annoying to be wrong because it terminates your game.

But I've recently been sent an implementation of the puzzle/board game ‘Mastermind’ for my puzzle collection, and I've been finding that the annoying randomness works the other way in that: it's much more annoying to be right. When you've just constructed a guess which you've carefully designed to narrow down the possibilities and bring you one step nearer to the actual solution … it's terribly irritating if that guess turns out to be the exact answer. In a game played against an opponent, where each of you was scoring points for how quickly you solved the other's problems, this would at least be useful to you because you'd get a lot of points for it. But in a solo context, you're not really after the high scores; you're after the satisfaction of reasoning your way to the answer step by step, and to unexpectedly hit the right combination at an early stage rather spoils the fun.

My broadband connection has started working again. It's been down for three days, and annoying as I was finding it I was also rather hoping it would stay down until the NTL engineer arrived, so that he could see it being down right in front of him and also so it would be obvious whether he'd really fixed anything or not. Now I have a nasty feeling he'll prod ineffectually at it and fail to address the root cause.

Perhaps it wouldn't be such a bad idea to find an alternative means of receiving broadcast TV and say goodbye to NTL completely…

I've done something horrid to my right forefinger, which is making typing alternately painful and inconvenient (depending on whether I'm currently remembering not to use it). I hope it'll go away by itself and I won't have to shift it by extreme measures such as laying off keyboards…

I collected a new pair of glasses today (my left eye has apparently become marginally less short-sighted, which I suppose is nice). They give me more peripheral vision than the old ones, which is good; but the arms are completely the wrong length and don't hook behind my ears properly. I suspect a trip back to Boots is in order, annoyingly.

Two of the four self-service checkouts in Tesco were out of order when I went there to buy my lunch today. Two days ago it was a different (but overlapping) pair. Is it really so hard to get them all working at the same time?

And my watch, whose battery I had changed a few weeks ago, gave me a battery warning today. It changed its mind fairly fast, but I worry that it might be time for a new one of those as well.

Add that lot to my ongoing NTL woes and my (landlord's) washing machine packing up and you're looking at a pretty annoyed Simon, who's currently hoping to see at least one thing working exactly as designed in the course of this week. Grrr.

On the plus side, this diary is now mirrored into a third location (*waves* to any new readers gained thereby), and today somebody sent me a Sudoku puzzle with the clues arranged into the shape of my initials. (3x3:a4_1_7e2c3d9h5d3_2_8b9_7_6b1f5a9f2a5b7c4a6c1_6_3e, for anyone with a copy of my ‘Solo’ program.)

The washing machine in my (rented) flat is becoming unusable. I've been suspecting for ages that it isn't rinsing entirely properly, but last night I had to run two and a bit washes on the same load to get it to do anything even remotely resembling a rinse. I fear a call to the landlord is in order, and that probably means I'll have to be at home at some point to take delivery of a new washing machine.

My broadband connection has been out since some time on Monday evening. I suspect that this is related to NTL's recent letter saying they were going to upgrade my bandwidth by over a factor of two and I didn't have to do anything, although the unbelievably slow phone drone I spoke to this morning outright refused to answer a complicated question like ‘have you upgraded me yet’, preferring instead to take over half an hour to schedule an engineer appointment. Which won't be until Saturday; until then I'm reduced to carrying a floppy disk between work and home containing any data I want to have available on my home machine.

Annoyingly, I had an NTL engineer come round last week, and I did ask him – while he was around anyway – whether my rather old cable modem would be able to cope with the upgraded service. He phoned a friend and said yes. I fear he is not going to be a millionaire.

One food I've particularly missed since being diagnosed coeliac in February is pies. I never used to eat that many of them, but I always enjoyed them a lot when I did. But gluten-free pastry is not the easiest of things to make, so I regretfully resigned myself to a pie-free life.

Yesterday I decided to make a pie regardless, using gluten-free flour for the pastry; I had found some GF flour which (a) had a pastry recipe on the side of the pack and (b) came recommended taste-wise by a non-coeliac (which tends to mean they can't easily tell the difference). Got to be worth a try, I thought.

In fact I didn't end up making the pie myself, due to mentioning the plan to Gareth and Verity on the phone; the next thing I knew it was being made at the Gallery on the grounds that they already had all the necessary equipment whereas I'd have had to go and buy it first, and also Verity did most of the work on grounds of having a lot more pastry-cooking experience. The result was definitely not indistinguishable from normal pastry; but it was undeniably a beef and mushroom pie, and it was the first pastry I'd eaten since February, and mmmmmmmm. Definitely something I'll attempt myself at some point.

In other news, this is possibly one of the more surprising ways to find out what became of one of your exes: http://icbirmingham.icnetwork.co.uk/mail/news/tm_objectid=15642946&method=full&siteid=50002&headline=mp-in-love-child-shock-name_page.html.

I've just returned from spending the entire afternoon at the LiveJournal Memetic Flash Mob Picnic. For those who aren't reading this on LJ or who have unaccountably managed not to have any other friends spreading the meme: some anonymous person declared a few weeks ago that there would be a picnic on Jesus Green in Cambridge, named a precise location and time, and said ‘tell your friends’. The meme propagated widely, as memes do, and quite a few people turned up.

It occurred to me that it would be cunning to bring along a load of sticky labels on which people could write their usernames, to eliminate all the hassle of actually asking people who they were so that everyone could move straight on to the inevitable ‘Oh, so you're So-and-so’ stage. So in a fit of public-spiritedness and organisation, I did that.

As a result I'm uniquely well placed to provide a head count for the picnic as a whole. Of the four sheets of 28 labels I brought along, we got through exactly three, which is 84 labels. Four people took two labels for various reasons, and I counted fourteen people who weren't labelled for various reasons. Therefore, although it is of course possible that I miscounted one or both of those adjustment figures, I can state with a reasonably high degree of confidence that the total turnout was in the region of 94 people.

It's strange how disappointing that feels. At 75-85, we were thinking ‘wow, this worked really well’. But where 85 feels like a success, 94 feels like a failure, because with only six more we could have got into triple figures :-)

I was expecting not to be able to post this now, because my home network connection has been down since yesterday evening. I rang NTL this morning and they insisted that it was a problem with my cable modem, and promised to send an engineer out on Wednesday. Now I return from the picnic and it's working fine. However, I have had long outages like this quite often recently, so I wonder if in fact it is a problem with my cable modem; I think I might not cancel the appointment, let them replace it on Wednesday regardless, and see if it stops happening…