COMPETITION ENTRY #34: WALL OF CHINA
There's one country above all others, isn't there, that is indelibly associated with walls and has been throughout a huge chunk of its history. No, not that one; I mean China. Their Great Wall is so renowned that it is allegedly visible from space (not entirely true but it makes a good story), and domestic brands of wine and light trucks have been named after it. And while it was built to keep out some hostile invaders - such as a certain Mr G. Khan and his Golden Horde - these days, the regime that holds China in a vice-like grip is more likely to want to keep its people in. Just ask anyone who was marooned in East Germany from 1961 onwards...
Now, the Chinese Communist Party has unleashed its latest weapon upon those who would defect from its borders. No, not that one; I mean a wall that moves to block the would-be escapee. And in this game - you guessed it! - you play that escapee. You are the inverse quotation mark - see it as a couple of eyes peering out of a hood of some kind, because you don't want to be identified too easily - and you must reach the goal, a line of dithered graphics. Trying to stop you will be an inverse colon, the movable wall sent by President Xi Jinping himself. Why I'm telling you all this I have no idea, because it's all explained on the title screen, alongside a scrolling message showing the controls (Q/A/O/P, because it's not 1982 and we're far beyond using the cursor keys). In fact, the title screen is somewhat familiar because it's the same initial setup as was used for Snail Maze...
You'll have no problem clearing the first screen. You can move faster than the wall, and diagonal controls are allowed. So within a couple of seconds at most: "YOU WIN". Except... you don't. There is no promised land over the dithered-graphics barrier, just another obstacle to be cleared; the movable wall has grown to two character squares. And then to three, four, five... and suddenly it's getting harder to avoid. Salvador says that the best score he could manage in this game is escaping 19 times, at least according to the score counter; I've gone one better, and escaped 20 times. Don't get too carried away, though; there is a mistake, in that if you are caught on your first attempt (i.e. the wall is only one square), you'll be told "you have escaped 1 times" (sic), so in reality I've made 19 escapes and succumbed to the inevitable when the wall was 20 squares long. I'm also not sure the collision detection is totally reliable - it seems that the detection happens before the wall has moved onto the square it's detecting, though it could be that the wall blinks so much when it's beyond about 15 squares.
If it isn't already obvious from this review, all too soon you will realise that there is no victory condition; it's a euphemism for life under a communist regime. "Don't try to escape, because we will catch you." The wall will always keep on growing until it spans the entire playing area - which is 24 squares, as the game uses the INPUT area as well as the main part of the screen. It is not possible to pass 23 squares, and probably not 22 either, due to the way the collision detection works - you have to move three squares to pass the wall completely, during which time it will be moving diagonally towards you. I have not yet managed to beat the wall at 20 squares without gratuitous save state abuse, but I can confirm it is possible - so that is as good a victory condition as we'll ever get, even though the game will still continue for one more round to seal your inevitable fate.
As with all Salvador's games this year, it was written in C and compiled using Z88DK, and the source code is available. This does mean it runs fast and smoothly, way more than it would had it been written in BASIC. It also means it far exceeds anything seen on Cassette 50; apparently this game was inspired by a screenshot from one of the games, but I can't work out which one it was, or whether it was from the Spectrum or ZX81 version. And while it's not much more than a two-and-two - Salvador even gave away that it took only two hours to write from start to finish - its BASIC equivalent would still be good for a type-in (and probably Cassette 50 as well).
Most significantly, with this seventh ZX81 entry for the year, another CSSCGC record has been equalled - and as Salvador says he has another program due for submission in August, which I assume will also be for the ZX81, the record will fall sooner rather than later. Somewhere, at least in my imagination, a bald-headed man with a ginger beard is smiling contentedly to himself.